Commit Graph

1041 Commits

Author SHA1 Message Date
Yi Min Zhao 2c1a48f2e5 KVM: S390: add new group for flic
In some cases, userspace needs to get or set all ais states for example
migration. So we introduce a new group KVM_DEV_FLIC_AISM_ALL to provide
interfaces to get or set the adapter-interruption-suppression mode for
all ISCs. The corresponding documentation is updated.

Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:41:07 +02:00
Christian Borntraeger 6ae1574c2a KVM: s390: implement instruction execution protection for emulated
ifetch

While currently only used to fetch the original instruction on failure
for getting the instruction length code, we should make the page table
walking code future proof.

Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:41:06 +02:00
Claudio Imbrenda 4036e3874a KVM: s390: ioctls to get and set guest storage attributes
* Add the struct used in the ioctls to get and set CMMA attributes.
* Add the two functions needed to get and set the CMMA attributes for
  guest pages.
* Add the two ioctls that use the aforementioned functions.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:41:06 +02:00
Claudio Imbrenda 190df4a212 KVM: s390: CMMA tracking, ESSA emulation, migration mode
* Add a migration state bitmap to keep track of which pages have dirty
  CMMA information.
* Disable CMMA by default, so we can track if it's used or not. Enable
  it on first use like we do for storage keys (unless we are doing a
  migration).
* Creates a VM attribute to enter and leave migration mode.
* In migration mode, CMMA is disabled in the SIE block, so ESSA is
  always interpreted and emulated in software.
* Free the migration state on VM destroy.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-06-22 12:41:05 +02:00
Heiko Carstens a752598254 s390: rename struct psw_bits members
Rename a couple of the struct psw_bits members so it is more obvious
for what they are good. Initially I thought using the single character
names from the PoP would be sufficient and obvious, but admittedly
that is not true.

The current implementation is not easy to use, if one has to look into
the source file to figure out which member represents the 'per' bit
(which is the 'r' member).

Therefore rename the members to sane names that are identical to the
uapi psw mask defines:

r -> per
i -> io
e -> ext
t -> dat
m -> mcheck
w -> wait
p -> pstate

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:26:02 +02:00
Heiko Carstens 8bb3fdd686 s390: rename psw_bits enums
The address space enums that must be used when modifying the address
space part of a psw with the psw_bits() macro can easily be confused
with the psw defines that are used to mask and compare directly the
mask part of a psw.
We have e.g. PSW_AS_PRIMARY vs PSW_ASC_PRIMARY.

To avoid confusion rename the PSW_AS_* enums to PSW_BITS_AS_*.

In addition also rename the PSW_AMODE_* enums, so they also follow the
same naming scheme: PSW_BITS_AMODE_*.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12 16:26:02 +02:00
Radim Krčmář 2fa6e1e12a KVM: add kvm_request_pending
A first step in vcpu->requests encapsulation.  Additionally, we now
use READ_ONCE() when accessing vcpu->requests, which ensures we
always load vcpu->requests when it's accessed.  This is important as
other threads can change it any time.  Also, READ_ONCE() documents
that vcpu->requests is used with other threads, likely requiring
memory barriers, which it does.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
[ Documented the new use of READ_ONCE() and converted another check
  in arch/mips/kvm/vz.c ]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-04 16:53:00 +02:00
Christian Borntraeger 1ba15b24f0 KVM: s390: fix ais handling vs cpu model
If ais is disabled via cpumodel, we must act accordingly, even if
KVM_CAP_S390_AIS was enabled.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
2017-05-31 19:54:49 +02:00
Linus Torvalds bf5f89463f Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - the rest of MM

 - various misc things

 - procfs updates

 - lib/ updates

 - checkpatch updates

 - kdump/kexec updates

 - add kvmalloc helpers, use them

 - time helper updates for Y2038 issues. We're almost ready to remove
   current_fs_time() but that awaits a btrfs merge.

 - add tracepoints to DAX

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  drivers/staging/ccree/ssi_hash.c: fix build with gcc-4.4.4
  selftests/vm: add a test for virtual address range mapping
  dax: add tracepoint to dax_insert_mapping()
  dax: add tracepoint to dax_writeback_one()
  dax: add tracepoints to dax_writeback_mapping_range()
  dax: add tracepoints to dax_load_hole()
  dax: add tracepoints to dax_pfn_mkwrite()
  dax: add tracepoints to dax_iomap_pte_fault()
  mtd: nand: nandsim: convert to memalloc_noreclaim_*()
  treewide: convert PF_MEMALLOC manipulations to new helpers
  mm: introduce memalloc_noreclaim_{save,restore}
  mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC
  mm/huge_memory.c: deposit a pgtable for DAX PMD faults when required
  mm/huge_memory.c: use zap_deposited_table() more
  time: delete CURRENT_TIME_SEC and CURRENT_TIME
  gfs2: replace CURRENT_TIME with current_time
  apparmorfs: replace CURRENT_TIME with current_time()
  lustre: replace CURRENT_TIME macro
  fs: ubifs: replace CURRENT_TIME_SEC with current_time
  fs: ufs: use ktime_get_real_ts64() for birthtime
  ...
2017-05-08 18:17:56 -07:00
Michal Hocko 752ade68cb treewide: use kv[mz]alloc* rather than opencoded variants
There are many code paths opencoding kvmalloc.  Let's use the helper
instead.  The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator.  E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation.  This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously.  There is no guarantee something like that happens
though.

This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.

Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Santosh Raspatur <santosh@chelsio.com>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Yishai Hadas <yishaih@mellanox.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:13 -07:00
Linus Torvalds 2d3e4866de * ARM: HYP mode stub supports kexec/kdump on 32-bit; improved PMU
support; virtual interrupt controller performance improvements; support
 for userspace virtual interrupt controller (slower, but necessary for
 KVM on the weird Broadcom SoCs used by the Raspberry Pi 3)
 
 * MIPS: basic support for hardware virtualization (ImgTec
 P5600/P6600/I6400 and Cavium Octeon III)
 
 * PPC: in-kernel acceleration for VFIO
 
 * s390: support for guests without storage keys; adapter interruption
 suppression
 
 * x86: usual range of nVMX improvements, notably nested EPT support for
 accessed and dirty bits; emulation of CPL3 CPUID faulting
 
 * generic: first part of VCPU thread request API; kvm_stat improvements
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - HYP mode stub supports kexec/kdump on 32-bit
   - improved PMU support
   - virtual interrupt controller performance improvements
   - support for userspace virtual interrupt controller (slower, but
     necessary for KVM on the weird Broadcom SoCs used by the Raspberry
     Pi 3)

  MIPS:
   - basic support for hardware virtualization (ImgTec P5600/P6600/I6400
     and Cavium Octeon III)

  PPC:
   - in-kernel acceleration for VFIO

  s390:
   - support for guests without storage keys
   - adapter interruption suppression

  x86:
   - usual range of nVMX improvements, notably nested EPT support for
     accessed and dirty bits
   - emulation of CPL3 CPUID faulting

  generic:
   - first part of VCPU thread request API
   - kvm_stat improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
  kvm: nVMX: Don't validate disabled secondary controls
  KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick
  Revert "KVM: Support vCPU-based gfn->hva cache"
  tools/kvm: fix top level makefile
  KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING
  KVM: Documentation: remove VM mmap documentation
  kvm: nVMX: Remove superfluous VMX instruction fault checks
  KVM: x86: fix emulation of RSM and IRET instructions
  KVM: mark requests that need synchronization
  KVM: return if kvm_vcpu_wake_up() did wake up the VCPU
  KVM: add explicit barrier to kvm_vcpu_kick
  KVM: perform a wake_up in kvm_make_all_cpus_request
  KVM: mark requests that do not need a wakeup
  KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up
  KVM: x86: always use kvm_make_request instead of set_bit
  KVM: add kvm_{test,clear}_request to replace {test,clear}_bit
  s390: kvm: Cpu model support for msa6, msa7 and msa8
  KVM: x86: remove irq disablement around KVM_SET_CLOCK/KVM_GET_CLOCK
  kvm: better MWAIT emulation for guests
  KVM: x86: virtualize cpuid faulting
  ...
2017-05-08 12:37:56 -07:00
Linus Torvalds b68e7e952f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:

 - three merges for KVM/s390 with changes for vfio-ccw and cpacf. The
   patches are included in the KVM tree as well, let git sort it out.

 - add the new 'trng' random number generator

 - provide the secure key verification API for the pkey interface

 - introduce the z13 cpu counters to perf

 - add a new system call to set up the guarded storage facility

 - simplify TASK_SIZE and arch_get_unmapped_area

 - export the raw STSI data related to CPU topology to user space

 - ... and the usual churn of bug-fixes and cleanups.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (74 commits)
  s390/crypt: use the correct module alias for paes_s390.
  s390/cpacf: Introduce kma instruction
  s390/cpacf: query instructions use unique parameters for compatibility with KMA
  s390/trng: Introduce s390 TRNG device driver.
  s390/crypto: Provide s390 specific arch random functionality.
  s390/crypto: Add new subfunctions to the cpacf PRNO function.
  s390/crypto: Renaming PPNO to PRNO.
  s390/pageattr: avoid unnecessary page table splitting
  s390/mm: simplify arch_get_unmapped_area[_topdown]
  s390/mm: make TASK_SIZE independent from the number of page table levels
  s390/gs: add regset for the guarded storage broadcast control block
  s390/kvm: Add use_cmma field to mm_context_t
  s390/kvm: Add PGSTE manipulation functions
  vfio: ccw: improve error handling for vfio_ccw_mdev_remove
  vfio: ccw: remove unnecessary NULL checks of a pointer
  s390/spinlock: remove compare and delay instruction
  s390/spinlock: use atomic primitives for spinlocks
  s390/cpumf: simplify detection of guest samples
  s390/pci: remove forward declaration
  s390/pci: increase the PCI_NR_FUNCTIONS default
  ...
2017-05-02 09:50:09 -07:00
Radim Krčmář 72875d8a4d KVM: add kvm_{test,clear}_request to replace {test,clear}_bit
Users were expected to use kvm_check_request() for testing and clearing,
but request have expanded their use since then and some users want to
only test or do a faster clear.

Make sure that requests are not directly accessed with bit operations.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-27 14:12:22 +02:00
Jason J. Herne e000b8e096 s390: kvm: Cpu model support for msa6, msa7 and msa8
msa6 and msa7 require no changes.
msa8 adds kma instruction and feature area.

Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-26 14:19:01 +02:00
Harald Freudenberger 985a9d20da s390/crypto: Renaming PPNO to PRNO.
The PPNO (Perform Pseudorandom Number Operation) instruction
has been renamed to PRNO (Perform Random Number Operation).
To avoid confusion and conflicts with future extensions with
this instruction (like e.g. provide a true random number
generator) this patch renames all occurences in cpacf.h and
adjusts the only exploiter code which is the prng device
driver and one line in the s390 kvm feature check.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-04-26 13:41:32 +02:00
Martin Schwidefsky ee71d16d22 s390/mm: make TASK_SIZE independent from the number of page table levels
The TASK_SIZE for a process should be maximum possible size of the address
space, 2GB for a 31-bit process and 8PB for a 64-bit process. The number
of page table levels required for a given memory layout is a consequence
of the mapped memory areas and their location.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-04-25 07:47:32 +02:00
Farhan Ali 730cd632c4 KVM: s390: Support keyless subset guest mode
If the KSS facility is available on the machine, we also make it
available for our KVM guests.

The KSS facility bypasses storage key management as long as the guest
does not issue a related instruction. When that happens, the control is
returned to the host, which has to turn off KSS for a guest vcpu
before retrying the instruction.

Signed-off-by: Corey S. McQuay <csmcquay@linux.vnet.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-21 11:08:11 +02:00
Christian Borntraeger 8024855999 KVM: s390: fix stale machine check data for guarded storage
When delivering a machine check the CPU state is "loaded", which
means that some registers are already in the host registers.
Before writing the register content into the machine check
save area, we must make sure that we save the content of the
registers into the data structures that are used for delivering
the machine check.
We already do the right thing for access, vector/floating point
registers, let's do the same for guarded storage.

Fixes: 4e0b1ab72b ("KVM: s390: gs support for kvm guests")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-04-12 13:48:35 +02:00
Christian Borntraeger fe722d13e3 KVM: s390: Fix sdnxo setting for nested guests
If the guest does not use the host register management, but it uses
the sdnx area, we must fill in a proper sdnxo value (address of sdnx
and the sdnxc).

Reported-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-04-12 13:47:31 +02:00
Yi Min Zhao 47a4693e1d KVM: s390: introduce AIS capability
Introduce a cap to enable AIS facility bit, and add documentation
for this capability.

Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-07 09:11:11 +02:00
Yi Min Zhao a892095013 KVM: s390: introduce adapter interrupt inject function
Inject adapter interrupts on a specified adapter which allows to
retrieve the adapter flags, e.g. if the adapter is subject to AIS
facility or not. And add documentation for this interface.

For adapters subject to AIS, handle the airq injection suppression
for a given ISC according to the interruption mode:
- before injection, if NO-Interruptions Mode, just return 0 and
  suppress, otherwise, allow the injection.
- after injection, if SINGLE-Interruption Mode, change it to
  NO-Interruptions Mode to suppress the following interrupts.

Besides, add tracepoint for suppressed airq and AIS mode transitions.

Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-06 13:15:37 +02:00
Fei Li 5197839354 KVM: s390: introduce ais mode modify function
Provide an interface for userspace to modify AIS
(adapter-interruption-suppression) mode state, and add documentation
for the interface. Allowed target modes are ALL-Interruptions mode
and SINGLE-Interruption mode.

We introduce the 'simm' and 'nimm' fields in kvm_s390_float_interrupt
to store interruption modes for each ISC. Each bit in 'simm' and
'nimm' targets to one ISC, and collaboratively indicate three modes:
ALL-Interruptions, SINGLE-Interruption and NO-Interruptions. This
interface can initiate most transitions between the states; transition
from SINGLE-Interruption to NO-Interruptions via adapter interrupt
injection will be introduced in a following patch. The meaningful
combinations are as follows:

    interruption mode | simm bit | nimm bit
    ------------------|----------|----------
             ALL      |    0     |     0
           SINGLE     |    1     |     0
             NO       |    1     |     1

Besides, add tracepoint to track AIS mode transitions.

Co-Authored-By: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-06 13:15:36 +02:00
Fei Li 08fab50da6 KVM: s390: interface for suppressible I/O adapters
In order to properly implement adapter-interruption suppression, we
need a way for userspace to specify which adapters are subject to
suppression. Let's convert the existing (and unused) 'pad' field into
a 'flags' field and define a flag value for suppressible adapters.

Besides, add documentation for the interface.

Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-06 13:15:36 +02:00
Heiko Carstens 232b8e3b1d KVM: s390: remove change-recording override support
Change-recording override (CO) was never implemented in any
machine. According to the architecture it is unpredictable if a
translation-specification exception will be recognized if the bit is
set and EDAT1 does not apply.
Therefore the easiest solution is to simply ignore the bit.

This also fixes commit cd1836f583 ("KVM: s390:
instruction-execution-protection support"). A guest may enable
instruction-execution-protection (IEP) but not EDAT1. In such a case
the guest_translate() function (arch/s390/kvm/gaccess.c) will report a
specification exception on pages that have the IEP bit set while it
should not.

It might make sense to add full IEP support to guest_translate() and
the GACC_IFETCH case. However, as far as I can tell the GACC_IFETCH
case is currently only used after an instruction was executed in order
to fetch the failing instruction. So there is no additional problem
*currently*.

Fixes: cd1836f583 ("KVM: s390: instruction-execution-protection support")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-04-03 12:45:08 +02:00
Fan Zhang 4e0b1ab72b KVM: s390: gs support for kvm guests
This patch adds guarded storage support for KVM guest. We need to
setup the necessary control blocks, the kvm_run structure for the
new registers, the necessary wrappers for VSIE, as well as the
machine check save areas.
GS is enabled lazily and the register saving and reloading is done in
KVM code.  As this feature adds new content for migration, we provide
a new capability for enablement (KVM_CAP_S390_GS).

Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-03-22 18:59:33 +01:00
Christian Borntraeger 7c2b3e0ddc Merge remote-tracking branch 's390/guarded-storage' into kvms390/next 2017-03-22 18:54:52 +01:00
Martin Schwidefsky 916cda1aa1 s390: add a system call for guarded storage
This adds a new system call to enable the use of guarded storage for
user space processes. The system call takes two arguments, a command
and pointer to a guarded storage control block:

    s390_guarded_storage(int command, struct gs_cb *gs_cb);

The second argument is relevant only for the GS_SET_BC_CB command.

The commands in detail:

0 - GS_ENABLE
    Enable the guarded storage facility for the current task. The
    initial content of the guarded storage control block will be
    all zeros. After the enablement the user space code can use
    load-guarded-storage-controls instruction (LGSC) to load an
    arbitrary control block. While a task is enabled the kernel
    will save and restore the current content of the guarded
    storage registers on context switch.
1 - GS_DISABLE
    Disables the use of the guarded storage facility for the current
    task. The kernel will cease to save and restore the content of
    the guarded storage registers, the task specific content of
    these registers is lost.
2 - GS_SET_BC_CB
    Set a broadcast guarded storage control block. This is called
    per thread and stores a specific guarded storage control block
    in the task struct of the current task. This control block will
    be used for the broadcast event GS_BROADCAST.
3 - GS_CLEAR_BC_CB
    Clears the broadcast guarded storage control block. The guarded-
    storage control block is removed from the task struct that was
    established by GS_SET_BC_CB.
4 - GS_BROADCAST
    Sends a broadcast to all thread siblings of the current task.
    Every sibling that has established a broadcast guarded storage
    control block will load this control block and will be enabled
    for guarded storage. The broadcast guarded storage control block
    is used up, a second broadcast without a refresh of the stored
    control block with GS_SET_BC_CB will not have any effect.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-03-22 08:14:25 +01:00
Farhan Ali 947b897204 KVM: s390: Use defines for intercept code
Let's use #define values for better readability.

Signed-off-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-03-21 11:10:35 +01:00
David Hildenbrand 0c9d86833d KVM: s390: use defines for execution controls
Let's replace the bitmasks by defines. Reconstructed from code, comments
and commit messages.

Tried to keep the defines short and map them to feature names. In case
they don't completely map to features, keep them in the stye of ICTL
defines.

This effectively drops all "U" from the existing numbers. I think this
should be fine (as similarly done for e.g. ICTL defines).

I am not 100% sure about the ECA_MVPGI and ECA_PROTEXCI bits as they are
always used in pairs.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170313104828.13362-1-david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[some renames, add one missing place]
2017-03-16 13:05:10 +01:00
Christian Borntraeger c0a6bfdc18 KVM: s390: Handle sthyi also for instruction intercept
Right now we handle the STHYI only via the operation exception intercept
(illegal instruction). If hardware ever decides to provide an
instruction intercept for STHYI, we should handle that as well.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-03-16 13:04:38 +01:00
Christian Borntraeger 4d5f2c04c8 KVM: s390: log runtime instrumentation enablement
We handle runtime instrumentation enablement either lazy or via
sync_regs on migration. Make sure to add a debug log entry for that
per CPU on the first occurrence.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-03-16 13:04:37 +01:00
Ingo Molnar 589ee62844 sched/headers: Prepare to remove the <linux/mm_types.h> dependency from <linux/sched.h>
Update code that relied on sched.h including various MM types for them.

This will allow us to remove the <linux/mm_types.h> include from <linux/sched.h>.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:37 +01:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Linus Torvalds fd7e9a8834 4.11 is going to be a relatively large release for KVM, with a little over
200 commits and noteworthy changes for most architectures.
 
 * ARM:
 - GICv3 save/restore
 - cache flushing fixes
 - working MSI injection for GICv3 ITS
 - physical timer emulation
 
 * MIPS:
 - various improvements under the hood
 - support for SMP guests
 - a large rewrite of MMU emulation.  KVM MIPS can now use MMU notifiers
 to support copy-on-write, KSM, idle page tracking, swapping, ballooning
 and everything else.  KVM_CAP_READONLY_MEM is also supported, so that
 writes to some memory regions can be treated as MMIO.  The new MMU also
 paves the way for hardware virtualization support.
 
 * PPC:
 - support for POWER9 using the radix-tree MMU for host and guest
 - resizable hashed page table
 - bugfixes.
 
 * s390: expose more features to the guest
 - more SIMD extensions
 - instruction execution protection
 - ESOP2
 
 * x86:
 - improved hashing in the MMU
 - faster PageLRU tracking for Intel CPUs without EPT A/D bits
 - some refactoring of nested VMX entry/exit code, preparing for live
 migration support of nested hypervisors
 - expose yet another AVX512 CPUID bit
 - host-to-guest PTP support
 - refactoring of interrupt injection, with some optimizations thrown in
 and some duct tape removed.
 - remove lazy FPU handling
 - optimizations of user-mode exits
 - optimizations of vcpu_is_preempted() for KVM guests
 
 * generic:
 - alternative signaling mechanism that doesn't pound on tsk->sighand->siglock
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "4.11 is going to be a relatively large release for KVM, with a little
  over 200 commits and noteworthy changes for most architectures.

  ARM:
   - GICv3 save/restore
   - cache flushing fixes
   - working MSI injection for GICv3 ITS
   - physical timer emulation

  MIPS:
   - various improvements under the hood
   - support for SMP guests
   - a large rewrite of MMU emulation. KVM MIPS can now use MMU
     notifiers to support copy-on-write, KSM, idle page tracking,
     swapping, ballooning and everything else. KVM_CAP_READONLY_MEM is
     also supported, so that writes to some memory regions can be
     treated as MMIO. The new MMU also paves the way for hardware
     virtualization support.

  PPC:
   - support for POWER9 using the radix-tree MMU for host and guest
   - resizable hashed page table
   - bugfixes.

  s390:
   - expose more features to the guest
   - more SIMD extensions
   - instruction execution protection
   - ESOP2

  x86:
   - improved hashing in the MMU
   - faster PageLRU tracking for Intel CPUs without EPT A/D bits
   - some refactoring of nested VMX entry/exit code, preparing for live
     migration support of nested hypervisors
   - expose yet another AVX512 CPUID bit
   - host-to-guest PTP support
   - refactoring of interrupt injection, with some optimizations thrown
     in and some duct tape removed.
   - remove lazy FPU handling
   - optimizations of user-mode exits
   - optimizations of vcpu_is_preempted() for KVM guests

  generic:
   - alternative signaling mechanism that doesn't pound on
     tsk->sighand->siglock"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (195 commits)
  x86/kvm: Provide optimized version of vcpu_is_preempted() for x86-64
  x86/paravirt: Change vcp_is_preempted() arg type to long
  KVM: VMX: use correct vmcs_read/write for guest segment selector/base
  x86/kvm/vmx: Defer TR reload after VM exit
  x86/asm/64: Drop __cacheline_aligned from struct x86_hw_tss
  x86/kvm/vmx: Simplify segment_base()
  x86/kvm/vmx: Get rid of segment_base() on 64-bit kernels
  x86/kvm/vmx: Don't fetch the TSS base from the GDT
  x86/asm: Define the kernel TSS limit in a macro
  kvm: fix page struct leak in handle_vmon
  KVM: PPC: Book3S HV: Disable HPT resizing on POWER9 for now
  KVM: Return an error code only as a constant in kvm_get_dirty_log()
  KVM: Return an error code only as a constant in kvm_get_dirty_log_protect()
  KVM: Return directly after a failed copy_from_user() in kvm_vm_compat_ioctl()
  KVM: x86: remove code for lazy FPU handling
  KVM: race-free exit from KVM_RUN without POSIX signals
  KVM: PPC: Book3S HV: Turn "KVM guest htab" message into a debug message
  KVM: PPC: Book3S PR: Ratelimit copy data failure error messages
  KVM: Support vCPU-based gfn->hva cache
  KVM: use separate generations for each address space
  ...
2017-02-22 18:22:53 -08:00
Linus Torvalds ff47d8c050 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:

 - New entropy generation for the pseudo random number generator.

 - Early boot printk output via sclp to help debug crashes on boot. This
   needs to be enabled with a kernel parameter.

 - Add proper no-execute support with a bit in the page table entry.

 - Bug fixes and cleanups.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (65 commits)
  s390/syscall: fix single stepped system calls
  s390/zcrypt: make ap_bus explicitly non-modular
  s390/zcrypt: Removed unneeded debug feature directory creation.
  s390: add missing "do {} while (0)" loop constructs to multiline macros
  s390/mm: add cond_resched call to kernel page table dumper
  s390: get rid of MACHINE_HAS_PFMF and MACHINE_HAS_HPAGE
  s390/mm: make memory_block_size_bytes available for !MEMORY_HOTPLUG
  s390: replace ACCESS_ONCE with READ_ONCE
  s390: Audit and remove any remaining unnecessary uses of module.h
  s390: mm: Audit and remove any unnecessary uses of module.h
  s390: kernel: Audit and remove any unnecessary uses of module.h
  s390/kdump: Use "LINUX" ELF note name instead of "CORE"
  s390: add no-execute support
  s390: report new vector facilities
  s390: use correct input data address for setup_randomness
  s390/sclp: get rid of common response code handling
  s390/sclp: don't add new lines to each printed string
  s390/sclp: make early sclp code readable
  s390/sclp: disable early sclp code as soon as the base sclp driver is active
  s390/sclp: move early printk code to drivers
  ...
2017-02-22 10:20:04 -08:00
Paolo Bonzini 460df4c1fc KVM: race-free exit from KVM_RUN without POSIX signals
The purpose of the KVM_SET_SIGNAL_MASK API is to let userspace "kick"
a VCPU out of KVM_RUN through a POSIX signal.  A signal is attached
to a dummy signal handler; by blocking the signal outside KVM_RUN and
unblocking it inside, this possible race is closed:

          VCPU thread                     service thread
   --------------------------------------------------------------
        check flag
                                          set flag
                                          raise signal
        (signal handler does nothing)
        KVM_RUN

However, one issue with KVM_SET_SIGNAL_MASK is that it has to take
tsk->sighand->siglock on every KVM_RUN.  This lock is often on a
remote NUMA node, because it is on the node of a thread's creator.
Taking this lock can be very expensive if there are many userspace
exits (as is the case for SMP Windows VMs without Hyper-V reference
time counter).

As an alternative, we can put the flag directly in kvm_run so that
KVM can see it:

          VCPU thread                     service thread
   --------------------------------------------------------------
                                          raise signal
        signal handler
          set run->immediate_exit
        KVM_RUN
          check run->immediate_exit

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:27:37 +01:00
Paul Gortmaker d321796753 s390: Audit and remove any remaining unnecessary uses of module.h
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each change instance
for the presence of either and replace as needed.  An instance
where module_param was used without moduleparam.h was also fixed,
as well as implicit use of ptrace.h and string.h headers.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-02-17 07:40:41 +01:00
Christian Borntraeger fb7dc1d4dd KVM: s390: detect some program check loops
Sometimes (e.g. early boot) a guest is broken in such ways that it loops
100% delivering operation exceptions (illegal operation) but the pgm new
PSW is not set properly. This will result in code being read from
address zero, which usually contains another illegal op. Let's detect
this case and return to userspace. Instead of only detecting
this for address zero apply a heuristic that will work for any program
check new psw.
We do not want guest problem state to be able to trigger a guest panic,
e.g. by faulting on an address that is the same as the program check
new PSW, so we check for the problem state bit being off.

With proper handling in userspace we
a: get rid of CPU consumption of such broken guests
b: keep the program old PSW. This allows to find out the original illegal
   operation - making debugging such early boot issues much easier than
   with single stepping

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-02-06 12:35:53 +01:00
Janosch Frank e1e8a9624f KVM: s390: Disable dirty log retrieval for UCONTROL guests
User controlled KVM guests do not support the dirty log, as they have
no single gmap that we can check for changes.

As they have no single gmap, kvm->arch.gmap is NULL and all further
referencing to it for dirty checking will result in a NULL
dereference.

Let's return -EINVAL if a caller tries to sync dirty logs for a
UCONTROL guest.

Fixes: 15f36eb ("KVM: s390: Add proper dirty bitmap support to S390 kvm.")
Cc: <stable@vger.kernel.org> # 3.16+

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reported-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-02-06 11:20:12 +01:00
Christian Borntraeger a8c39dd77c KVM: s390: Add debug logging to basic cpu model interface
Let's log something for changes in facilities, cpuid and ibc now that we
have a cpu model in QEMU. All of these calls are pretty seldom, so we
will not spill the log, the they will help to understand pontential
guest issues, for example if some instructions are fenced off.

As the s390 debug feature has a limited amount of parameters and
strings must not go away we limit the facility printing to 3 double
words, instead of building that list dynamically. This should be enough
for several years. If we ever exceed 3 double words then the logging
will be incomplete but no functional impact will happen.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:19:46 +01:00
Christian Borntraeger af0f339a6c KVM: s390: Fix for 4.10 (via kvm/master)
Fix a kernel memory exposure.
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Merge tag 'kvm-s390-master-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kernelorgnext

avoid merge conflicts, pull update for master
also into next.
2017-01-30 11:19:20 +01:00
David Hildenbrand a69cbe81b2 KVM: s390: guestdbg: filter PER i-fetch on EXECUTE properly
When we get a PER i-fetch event on an EXECUTE or EXECUTE RELATIVE LONG
instruction, because the executed instruction generated a PER i-fetch
event, then the PER address points at the EXECUTE function, not the
fetched one.

Therefore, when filtering PER events, we have to take care of the
really fetched instruction, which we can only get by reading in guest
virtual memory.

For icpt code 4 and 56, we directly have additional information about an
EXECUTE instruction at hand. For icpt code 8, we always have to read
in guest virtual memory.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[small fixes]
2017-01-30 11:19:17 +01:00
David Hildenbrand 3fa8cad740 KVM: s390: prepare to read random guest instructions
We will have to read instructions not residing at the current PSW
address.

Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:19:16 +01:00
David Hildenbrand f41711788c KVM: s390: guestdbg: filter i-fetch events on icpts
We already filter PER events reported via icpt code 8. For icpt code
4 and 56, this is still missing.

So let's properly detect if we have a debugging event and if we have to
inject a PER i-fetch event into the guest at all.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:19:16 +01:00
Guenther Hutzl 2f87d942be KVM: s390: Introduce BCD Vector Instructions to the guest
We can directly forward the vector BCD instructions to the guest
if available and VX is requested by user space.

Please note that user space will have to take care of the final state
of the facility bit when migrating to older machines.

Signed-off-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:17:30 +01:00
Maxim Samoylov 53743aa7f1 KVM: s390: Introduce Vector Enhancements facility 1 to the guest
We can directly forward the vector enhancement facility 1 to the guest
if available and VX is requested by user space.

Please note that user space will have to take care of the final state
of the facility bit when migrating to older machines.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Maxim Samoylov <max7255@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:17:29 +01:00
Christian Borntraeger 27f67f8727 KVM: s390: Get rid of ar_t
sparse with __CHECK_ENDIAN__ shows that ar_t was never properly
used across KVM on s390. We can now:
- fix all places
- do not make ar_t special
Since ar_t is just used as a register number (no endianness issues
for u8), and all other register numbers are also just plain int
variables, let's just use u8, which matches the __u8 in the userspace
ABI for the memop ioctl.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-30 11:17:29 +01:00
Heiko Carstens d051ae5313 KVM: s390: get rid of bogus cc initialization
The plo inline assembly has a cc output operand that is always written
to and is also as such an operand declared. Therefore the compiler is
free to omit the rather pointless and misleading initialization.

Get rid of this.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:17:28 +01:00
Janosch Frank cd1836f583 KVM: s390: instruction-execution-protection support
The new Instruction Execution Protection needs to be enabled before
the guest can use it. Therefore we pass the IEP facility bit to the
guest and enable IEP interpretation.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:17:28 +01:00
Christian Borntraeger a679c547d1 KVM: s390: gaccess: add ESOP2 handling
When we access guest memory and run into a protection exception, we
need to pass the exception data to the guest. ESOP2 provides detailed
information about all protection exceptions which ESOP1 only partially
provided.

The gaccess changes make sure, that the guest always gets all
available information.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2017-01-30 11:17:27 +01:00
Christian Borntraeger 0447819741 KVM: s390: do not expose random data via facility bitmap
kvm_s390_get_machine() populates the facility bitmap by copying bytes
from the host results that are stored in a 256 byte array in the prefix
page. The KVM code does use the size of the target buffer (2k), thus
copying and exposing unrelated kernel memory (mostly machine check
related logout data).

Let's use the size of the source buffer instead.  This is ok, as the
target buffer will always be greater or equal than the source buffer as
the KVM internal buffers (and thus S390_ARCH_FAC_LIST_SIZE_BYTE) cover
the maximum possible size that is allowed by STFLE, which is 256
doublewords. All structures are zero allocated so we can leave bytes
256-2047 unchanged.

Add a similar fix for kvm_arch_init_vm().

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
[found with smatch]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
CC: stable@vger.kernel.org
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-20 15:29:34 +01:00
Heiko Carstens 0b92515916 s390: remove couple of unneeded semicolons
Remove a couple of unneeded semicolons. This is just to reduce the
noise that the coccinelle static code checker generates.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-01-16 07:27:54 +01:00
Thomas Gleixner 8b0e195314 ktime: Cleanup ktime_set() usage
ktime_set(S,N) was required for the timespec storage type and is still
useful for situations where a Seconds and Nanoseconds part of a time value
needs to be converted. For anything where the Seconds argument is 0, this
is pointless and can be replaced with a simple assignment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Christian Borntraeger e1788bb995 KVM: s390: handle floating point registers in the run ioctl not in vcpu_put/load
Right now we switch the host fprs/vrs in kvm_arch_vcpu_load and switch
back in kvm_arch_vcpu_put. This process is already optimized
since commit 9977e886cb ("s390/kernel: lazy restore fpu registers")
avoiding double save/restores on schedule. We still reload the pointers
and test the guest fpc on each context switch, though.

We can minimize the cost of vcpu_load/put by doing the test in the
VCPU_RUN ioctl itself. As most VCPU threads almost never exit to
userspace in the common fast path, this allows to avoid this overhead
for the common case (eventfd driven I/O, all exits including sleep
handled in the kernel) - making kvm_arch_vcpu_load/put basically
disappear in perf top.

Also adapt the fpu get/set ioctls.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-11-22 19:32:35 +01:00
Christian Borntraeger 31d8b8d41a KVM: s390: handle access registers in the run ioctl not in vcpu_put/load
Right now we save the host access registers in kvm_arch_vcpu_load
and load them in kvm_arch_vcpu_put. Vice versa for the guest access
registers. On schedule this means, that we load/save access registers
multiple times.

e.g. VCPU_RUN with just one reschedule and then return does

[from user space via VCPU_RUN]
- save the host registers in kvm_arch_vcpu_load (via ioctl)
- load the guest registers in kvm_arch_vcpu_load (via ioctl)
- do guest stuff
- decide to schedule/sleep
- save the guest registers in kvm_arch_vcpu_put (via sched)
- load the host registers in kvm_arch_vcpu_put (via sched)
- save the host registers in switch_to (via sched)
- schedule
- return
- load the host registers in switch_to (via sched)
- save the host registers in kvm_arch_vcpu_load (via sched)
- load the guest registers in kvm_arch_vcpu_load (via sched)
- do guest stuff
- decide to go to userspace
- save the guest registers in kvm_arch_vcpu_put (via ioctl)
- load the host registers in kvm_arch_vcpu_put (via ioctl)
[back to user space]

As the kernel does not use access registers, we can avoid
this reloading and simply piggy back on switch_to (let it save
the guest values instead of host values in thread.acrs) by
moving the host/guest switch into the VCPU_RUN ioctl function.
We now do

[from user space via VCPU_RUN]
- save the host registers in kvm_arch_vcpu_ioctl_run
- load the guest registers in kvm_arch_vcpu_ioctl_run
- do guest stuff
- decide to schedule/sleep
- save the guest registers in switch_to
- schedule
- return
- load the guest registers in switch_to (via sched)
- do guest stuff
- decide to go to userspace
- save the guest registers in kvm_arch_vcpu_ioctl_run
- load the host registers in kvm_arch_vcpu_ioctl_run

This seems to save about 10% of the vcpu_put/load functions
according to perf.

As vcpu_load no longer switches the acrs, We can also loading
the acrs in kvm_arch_vcpu_ioctl_set_sregs.

Suggested-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-11-22 19:32:35 +01:00
Janosch Frank 45c7ee43a5 KVM: s390: Fix STHYI buffer alignment for diag224
Diag224 requires a page-aligned 4k buffer to store the name table
into. kmalloc does not guarantee page alignment, hence we replace it
with __get_free_page for the buffer allocation.

Cc: stable@vger.kernel.org # v4.8+
Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-10-26 13:46:44 +02:00
Christian Borntraeger a5efb6b6c9 KVM: s390: reject invalid modes for runtime instrumentation
Usually a validity intercept is a programming error of the host
because of invalid entries in the state description.
We can get a validity intercept if the mode of the runtime
instrumentation control block is wrong. As the host does not know
which modes are valid, this can be used by userspace to trigger
a WARN.
Instead of printing a WARN let's return an error to userspace as
this can only happen if userspace provides a malformed initial
value (e.g. on migration). The kernel should never warn on bogus
input. Instead let's log it into the s390 debug feature.

While at it, let's return -EINVAL for all validity intercepts as
this will trigger an error in QEMU like

error: kvm run failed Invalid argument
PSW=mask 0404c00180000000 addr 000000000063c226 cc 00
R00=000000000000004f R01=0000000000000004 R02=0000000000760005 R03=000000007fe0a000
R04=000000000064ba2a R05=000000049db73dd0 R06=000000000082c4b0 R07=0000000000000041
R08=0000000000000002 R09=000003e0804042a8 R10=0000000496152c42 R11=000000007fe0afb0
[...]

This will avoid an endless loop of validity intercepts.

Cc: stable@vger.kernel.org # v4.5+
Fixes: c6e5f16637 ("KVM: s390: implement the RI support of guest")
Acked-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-10-20 20:06:12 +02:00
Linus Torvalds 6218590bcb KVM updates for v4.9-rc1
All architectures:
   Move `make kvmconfig` stubs from x86;  use 64 bits for debugfs stats.
 
 ARM:
   Important fixes for not using an in-kernel irqchip; handle SError
   exceptions and present them to guests if appropriate; proxying of GICV
   access at EL2 if guest mappings are unsafe; GICv3 on AArch32 on ARMv8;
   preparations for GICv3 save/restore, including ABI docs; cleanups and
   a bit of optimizations.
 
 MIPS:
   A couple of fixes in preparation for supporting MIPS EVA host kernels;
   MIPS SMP host & TLB invalidation fixes.
 
 PPC:
   Fix the bug which caused guests to falsely report lockups; other minor
   fixes; a small optimization.
 
 s390:
   Lazy enablement of runtime instrumentation; up to 255 CPUs for nested
   guests; rework of machine check deliver; cleanups and fixes.
 
 x86:
   IOMMU part of AMD's AVIC for vmexit-less interrupt delivery; Hyper-V
   TSC page; per-vcpu tsc_offset in debugfs; accelerated INS/OUTS in
   nVMX; cleanups and fixes.
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Merge tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "All architectures:
   - move `make kvmconfig` stubs from x86
   - use 64 bits for debugfs stats

  ARM:
   - Important fixes for not using an in-kernel irqchip
   - handle SError exceptions and present them to guests if appropriate
   - proxying of GICV access at EL2 if guest mappings are unsafe
   - GICv3 on AArch32 on ARMv8
   - preparations for GICv3 save/restore, including ABI docs
   - cleanups and a bit of optimizations

  MIPS:
   - A couple of fixes in preparation for supporting MIPS EVA host
     kernels
   - MIPS SMP host & TLB invalidation fixes

  PPC:
   - Fix the bug which caused guests to falsely report lockups
   - other minor fixes
   - a small optimization

  s390:
   - Lazy enablement of runtime instrumentation
   - up to 255 CPUs for nested guests
   - rework of machine check deliver
   - cleanups and fixes

  x86:
   - IOMMU part of AMD's AVIC for vmexit-less interrupt delivery
   - Hyper-V TSC page
   - per-vcpu tsc_offset in debugfs
   - accelerated INS/OUTS in nVMX
   - cleanups and fixes"

* tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (140 commits)
  KVM: MIPS: Drop dubious EntryHi optimisation
  KVM: MIPS: Invalidate TLB by regenerating ASIDs
  KVM: MIPS: Split kernel/user ASID regeneration
  KVM: MIPS: Drop other CPU ASIDs on guest MMU changes
  KVM: arm/arm64: vgic: Don't flush/sync without a working vgic
  KVM: arm64: Require in-kernel irqchip for PMU support
  KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register
  KVM: PPC: Book3S PR: Support 64kB page size on POWER8E and POWER8NVL
  KVM: PPC: Book3S: Remove duplicate setting of the B field in tlbie
  KVM: PPC: BookE: Fix a sanity check
  KVM: PPC: Book3S HV: Take out virtual core piggybacking code
  KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread
  ARM: gic-v3: Work around definition of gic_write_bpr1
  KVM: nVMX: Fix the NMI IDT-vectoring handling
  KVM: VMX: Enable MSR-BASED TPR shadow even if APICv is inactive
  KVM: nVMX: Fix reload apic access page warning
  kvmconfig: add virtio-gpu to config fragment
  config: move x86 kvm_guest.config to a common location
  arm64: KVM: Remove duplicating init code for setting VMID
  ARM: KVM: Support vgic-v3
  ...
2016-10-06 10:49:01 -07:00
Linus Torvalds e46cae4418 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "The new features and main improvements in this merge for v4.9

   - Support for the UBSAN sanitizer

   - Set HAVE_EFFICIENT_UNALIGNED_ACCESS, it improves the code in some
     places

   - Improvements for the in-kernel fpu code, in particular the overhead
     for multiple consecutive in kernel fpu users is recuded

   - Add a SIMD implementation for the RAID6 gen and xor operations

   - Add RAID6 recovery based on the XC instruction

   - The PCI DMA flush logic has been improved to increase the speed of
     the map / unmap operations

   - The time synchronization code has seen some updates

  And bug fixes all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits)
  s390/con3270: fix insufficient space padding
  s390/con3270: fix use of uninitialised data
  MAINTAINERS: update DASD maintainer
  s390/cio: fix accidental interrupt enabling during resume
  s390/dasd: add missing \n to end of dev_err messages
  s390/config: Enable config options for Docker
  s390/dasd: make query host access interruptible
  s390/dasd: fix panic during offline processing
  s390/dasd: fix hanging offline processing
  s390/pci_dma: improve lazy flush for unmap
  s390/pci_dma: split dma_update_trans
  s390/pci_dma: improve map_sg
  s390/pci_dma: simplify dma address calculation
  s390/pci_dma: remove dma address range check
  iommu/s390: simplify registration of I/O address translation parameters
  s390: migrate exception table users off module.h and onto extable.h
  s390: export header for CLP ioctl
  s390/vmur: fix irq pointer dereference in int handler
  s390/dasd: add missing KOBJ_CHANGE event for unformatted devices
  s390: enable UBSAN
  ...
2016-10-04 14:05:52 -07:00
Luiz Capitulino 235539b48a kvm: add stubs for arch specific debugfs support
Two stubs are added:

 o kvm_arch_has_vcpu_debugfs(): must return true if the arch
   supports creating debugfs entries in the vcpu debugfs dir
   (which will be implemented by the next commit)

 o kvm_arch_create_vcpu_debugfs(): code that creates debugfs
   entries in the vcpu debugfs dir

For x86, this commit introduces a new file to avoid growing
arch/x86/kvm/x86.c even more.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-16 16:57:47 +02:00
Christian Borntraeger b0eb91ae63 Merge remote-tracking branch 'kvms390/s390forkvm' into kvms390next 2016-09-08 13:41:08 +02:00
Markus Elfring 0624a8eb82 KVM: s390: Use memdup_user() rather than duplicating code
* Reuse existing functionality from memdup_user() instead of keeping
  duplicate source code.

  This issue was detected by using the Coccinelle software.

* Return directly if this copy operation failed.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Message-Id: <c86f7520-885e-2829-ae9c-b81caa898e84@users.sourceforge.net>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 13:40:55 +02:00
Markus Elfring a1708a2ead KVM: s390: Improve determination of sizes in kvm_s390_import_bp_data()
* A multiplication for the size determination of a memory allocation
  indicated that an array data structure should be processed.
  Thus reuse the corresponding function "kmalloc_array".

  Suggested-by: Paolo Bonzini <pbonzini@redhat.com>

  This issue was detected also by using the Coccinelle software.

* Replace the specification of data structures by pointer dereferences
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.

* Delete the local variable "size" which became unnecessary with
  this refactoring.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-Id: <c3323f6b-4af2-0bfb-9399-e529952e378e@users.sourceforge.net>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 13:40:54 +02:00
David Hildenbrand a6940674c3 KVM: s390: allow 255 VCPUs when sca entries aren't used
If the SCA entries aren't used by the hardware (no SIGPIF), we
can simply not set the entries, stick to the basic sca and allow more
than 64 VCPUs.

To hinder any other facility from using these entries, let's properly
provoke intercepts by not setting the MCN and keeping the entries
unset.

This effectively allows when running KVM under KVM (vSIE) or under z/VM to
provide more than 64 VCPUs to a guest. Let's limit it to 255 for now, to
not run into problems if the CPU numbers are limited somewhere else.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 13:40:53 +02:00
Fan Zhang 80cd876338 KVM: s390: lazy enable RI
Only enable runtime instrumentation if the guest issues an RI related
instruction or if userspace changes the riccb to a valid state.
This makes entry/exit a tiny bit faster.

Initial patch by Christian Borntraeger
Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 13:40:39 +02:00
Janosch Frank c14b88d766 KVM: s390: gaccess: simplify translation exception handling
The payload data for protection exceptions is a superset of the
payload of other translation exceptions. Let's set the additional
flags and use a fall through to minimize code duplication.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:53 +02:00
David Hildenbrand b1ffffbd0f KVM: s390: guestdbg: separate defines for per code
Let's avoid working with the PER_EVENT* defines, used for control register
manipulation, when checking the u8 PER code. Introduce separate defines
based on the existing defines.

Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:52 +02:00
David Hildenbrand 8953fb08ab KVM: s390: write external damage code on machine checks
Let's also write the external damage code already provided by
struct kvm_s390_mchk_info.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:52 +02:00
David Hildenbrand ff5dc1492a KVM: s390: fix delivery of vector regs during machine checks
Vector registers are only to be stored if the facility is available
and if the guest has set up the machine check extended save area.

If anything goes wrong while writing the vector registers, the vector
registers are to be marked as invalid. Please note that we are allowed
to write the registers although they are marked as invalid.

Machine checks and "store status" SIGP orders are two different concepts,
let's correctly separate these. As the SIGP part is completely handled in
user space, we can drop it.

This patch is based on a patch from Cornelia Huck.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:52 +02:00
David Hildenbrand 0319dae677 KVM: s390: split store status and machine check handling
Store status writes the prefix which is not to be done by a machine check.
Also, the psw is stored and later on overwritten by the failing-storage
address, which looks strange at first sight.

Store status and machine check handling look similar, but they are actually
two different things.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:51 +02:00
David Hildenbrand d6404ded30 KVM: s390: factor out actual delivery of machine checks
Let's factor this out to prepare for bigger changes. Reorder to calls to
match the logical order given in the PoP.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-09-08 09:07:51 +02:00
David Hildenbrand 4d21cef3ea KVM: s390: vsie: fix riccbd
We store the address of riccbd at the wrong location, overwriting
gvrd. This means that our nested guest will not be able to use runtime
instrumentation. Also, a memory leak, if our KVM guest actually sets gvrd.

Not noticed until now, as KVM guests never make use of gvrd and runtime
instrumentation wasn't completely tested yet.

Reported-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-09-05 13:48:50 +02:00
Martin Schwidefsky 69c0e360f9 s390/crypto: cpacf function detection
The CPACF code makes some assumptions about the availablity of hardware
support. E.g. if the machine supports KM(AES-256) without chaining it is
assumed that KMC(AES-256) with chaining is available as well. For the
existing CPUs this is true but the architecturally correct way is to
check each CPACF functions on its own. This is what the query function
of each instructions is all about.

Reviewed-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-29 11:05:09 +02:00
Martin Schwidefsky 88bf46bfde Merge branch 's390forkvm' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux
Pull facility mask patch from the KVM tree.

* tag 's390forkvm' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux
  KVM: s390: generate facility mask from readable list
2016-08-26 16:34:19 +02:00
Heiko Carstens f6c1d359be KVM: s390: generate facility mask from readable list
Automatically generate the KVM facility mask out of a readable list.
Manually changing the masks is very error prone, especially if the
special IBM bit numbering has to be considered.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-08-25 22:47:03 +02:00
David Hildenbrand a7d4b8f256 KVM: s390: don't use current->thread.fpu.* when accessing registers
As the meaning of these variables and pointers seems to change more
frequently, let's directly access our save area, instead of going via
current->thread.

Right now, this is broken for set/get_fpu. They simply overwrite the
host registers, as the pointers to the current save area were turned
into the static host save area.

Cc: stable@vger.kernel.org # 4.7
Fixes: 3f6813b9a5 ("s390/fpu: allocate 'struct fpu' with the task_struct")
Reported-by: Hao QingFeng <haoqf@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-08-25 17:33:24 +02:00
Julius Niedworok aca411a4b1 KVM: s390: reset KVM_REQ_MMU_RELOAD if mapping the prefix failed
When triggering KVM_RUN without a user memory region being mapped
(KVM_SET_USER_MEMORY_REGION) a validity intercept occurs. This could
happen, if the user memory region was not mapped initially or if it
was unmapped after the vcpu is initialized. The function
kvm_s390_handle_requests checks for the KVM_REQ_MMU_RELOAD bit. The
check function always clears this bit. If gmap_mprotect_notify
returns an error code, the mapping failed, but the KVM_REQ_MMU_RELOAD
was not set anymore. So the next time kvm_s390_handle_requests is
called, the execution would fall trough the check for
KVM_REQ_MMU_RELOAD. The bit needs to be resetted, if
gmap_mprotect_notify returns an error code. Resetting the bit with
kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu) fixes the bug.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Julius Niedworok <jniedwor@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-08-12 09:11:08 +02:00
Julius Niedworok 75a4615c95 KVM: s390: set the prefix initially properly
When KVM_RUN is triggered on a VCPU without an initial reset, a
validity intercept occurs.
Setting the prefix will set the KVM_REQ_MMU_RELOAD bit initially,
thus preventing the bug.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Julius Niedworok <jniedwor@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-08-12 09:10:17 +02:00
Linus Torvalds 221bb8a46e - ARM: GICv3 ITS emulation and various fixes. Removal of the old
VGIC implementation.
 
 - s390: support for trapping software breakpoints, nested virtualization
 (vSIE), the STHYI opcode, initial extensions for CPU model support.
 
 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
 preliminary to this and the upcoming support for hardware virtualization
 extensions.
 
 - x86: support for execute-only mappings in nested EPT; reduced vmexit
 latency for TSC deadline timer (by about 30%) on Intel hosts; support for
 more than 255 vCPUs.
 
 - PPC: bugfixes.
 
 The ugly bit is the conflicts.  A couple of them are simple conflicts due
 to 4.7 fixes, but most of them are with other trees. There was definitely
 too much reliance on Acked-by here.  Some conflicts are for KVM patches
 where _I_ gave my Acked-by, but the worst are for this pull request's
 patches that touch files outside arch/*/kvm.  KVM submaintainers should
 probably learn to synchronize better with arch maintainers, with the
 latter providing topic branches whenever possible instead of Acked-by.
 This is what we do with arch/x86.  And I should learn to refuse pull
 requests when linux-next sends scary signals, even if that means that
 submaintainers have to rebase their branches.
 
 Anyhow, here's the list:
 
 - arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
 by the nvdimm tree.  This tree adds handle_preemption_timer and
 EXIT_REASON_PREEMPTION_TIMER at the same place.  In general all mentions
 of pcommit have to go.
 
 There is also a conflict between a stable fix and this patch, where the
 stable fix removed the vmx_create_pml_buffer function and its call.
 
 - virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
 This tree adds kvm_io_bus_get_dev at the same place.
 
 - virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
 file was completely removed for 4.8.
 
 - include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
 this is a change that should have gone in through the irqchip tree and
 pulled by kvm-arm.  I think I would have rejected this kvm-arm pull
 request.  The KVM version is the right one, except that it lacks
 GITS_BASER_PAGES_SHIFT.
 
 - arch/powerpc: what a mess.  For the idle_book3s.S conflict, the KVM
 tree is the right one; everything else is trivial.  In this case I am
 not quite sure what went wrong.  The commit that is causing the mess
 (fd7bacbca4, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
 path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
 and arch/powerpc/kvm/.  It's large, but at 396 insertions/5 deletions
 I guessed that it wasn't really possible to split it and that the 5
 deletions wouldn't conflict.  That wasn't the case.
 
 - arch/s390: also messy.  First is hypfs_diag.c where the KVM tree
 moved some code and the s390 tree patched it.  You have to reapply the
 relevant part of commits 6c22c98637, plus all of e030c1125e, to
 arch/s390/kernel/diag.c.  Or pick the linux-next conflict
 resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
 Second, there is a conflict in gmap.c between a stable fix and 4.8.
 The KVM version here is the correct one.
 
 I have pushed my resolution at refs/heads/merge-20160802 (commit
 3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:

 - ARM: GICv3 ITS emulation and various fixes.  Removal of the
   old VGIC implementation.

 - s390: support for trapping software breakpoints, nested
   virtualization (vSIE), the STHYI opcode, initial extensions
   for CPU model support.

 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots
   of cleanups, preliminary to this and the upcoming support for
   hardware virtualization extensions.

 - x86: support for execute-only mappings in nested EPT; reduced
   vmexit latency for TSC deadline timer (by about 30%) on Intel
   hosts; support for more than 255 vCPUs.

 - PPC: bugfixes.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
  KVM: PPC: Introduce KVM_CAP_PPC_HTM
  MIPS: Select HAVE_KVM for MIPS64_R{2,6}
  MIPS: KVM: Reset CP0_PageMask during host TLB flush
  MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
  MIPS: KVM: Sign extend MFC0/RDHWR results
  MIPS: KVM: Fix 64-bit big endian dynamic translation
  MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
  MIPS: KVM: Use 64-bit CP0_EBase when appropriate
  MIPS: KVM: Set CP0_Status.KX on MIPS64
  MIPS: KVM: Make entry code MIPS64 friendly
  MIPS: KVM: Use kmap instead of CKSEG0ADDR()
  MIPS: KVM: Use virt_to_phys() to get commpage PFN
  MIPS: Fix definition of KSEGX() for 64-bit
  KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
  kvm: x86: nVMX: maintain internal copy of current VMCS
  KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
  KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
  KVM: arm64: vgic-its: Simplify MAPI error handling
  KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
  KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
  ...
2016-08-02 16:11:27 -04:00
Linus Torvalds 015cd867e5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "There are a couple of new things for s390 with this merge request:

   - a new scheduling domain "drawer" is added to reflect the unusual
     topology found on z13 machines.  Performance tests showed up to 8
     percent gain with the additional domain.

   - the new crc-32 checksum crypto module uses the vector-galois-field
     multiply and sum SIMD instruction to speed up crc-32 and crc-32c.

   - proper __ro_after_init support, this requires RO_AFTER_INIT_DATA in
     the generic vmlinux.lds linker script definitions.

   - kcov instrumentation support.  A prerequisite for that is the
     inline assembly basic block cleanup, which is the reason for the
     net/iucv/iucv.c change.

   - support for 2GB pages is added to the hugetlbfs backend.

  Then there are two removals:

   - the oprofile hardware sampling support is dead code and is removed.
     The oprofile user space uses the perf interface nowadays.

   - the ETR clock synchronization is removed, this has been superseeded
     be the STP clock synchronization.  And it always has been
     "interesting" code..

  And the usual bug fixes and cleanups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (82 commits)
  s390/pci: Delete an unnecessary check before the function call "pci_dev_put"
  s390/smp: clean up a condition
  s390/cio/chp : Remove deprecated create_singlethread_workqueue
  s390/chsc: improve channel path descriptor determination
  s390/chsc: sanitize fmt check for chp_desc determination
  s390/cio: make fmt1 channel path descriptor optional
  s390/chsc: fix ioctl CHSC_INFO_CU command
  s390/cio/device_ops: fix kernel doc
  s390/cio: allow to reset channel measurement block
  s390/console: Make preferred console handling more consistent
  s390/mm: fix gmap tlb flush issues
  s390/mm: add support for 2GB hugepages
  s390: have unique symbol for __switch_to address
  s390/cpuinfo: show maximum thread id
  s390/ptrace: clarify bits in the per_struct
  s390: stack address vs thread_info
  s390: remove pointless load within __switch_to
  s390: enable kcov support
  s390/cpumf: use basic block for ecctr inline assembly
  s390/hypfs: use basic block for diag inline assembly
  ...
2016-07-26 12:22:51 -07:00
David Hildenbrand 9acc317b18 KVM: s390: let ptff intercepts result in cc=3
We don't emulate ptff subfunctions, therefore react on any attempt of
execution by setting cc=3 (Requested function not available).

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-07-18 14:15:00 +02:00
David Hildenbrand 6502a34cfd KVM: s390: allow user space to handle instr 0x0000
We will use illegal instruction 0x0000 for handling 2 byte sw breakpoints
from user space. As it can be enabled dynamically via a capability,
let's move setting of ICTL_OPEREXC to the post creation step, so we avoid
any races when enabling that capability just while adding new cpus.

Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-07-18 14:15:00 +02:00
Radim Krčmář c63cf538eb KVM: pass struct kvm to kvm_set_routing_entry
Arch-specific code will use it.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-14 09:03:56 +02:00
David Hildenbrand 5ffe466cd3 KVM: s390: inject PER i-fetch events on applicable icpts
In case we have to emuluate an instruction or part of it (instruction,
partial instruction, operation exception), we have to inject a PER
instruction-fetching event for that instruction, if hardware told us to do
so.

In case we retry an instruction, we must not inject the PER event.

Please note that we don't filter the events properly yet, so guest
debugging will be visible for the guest.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-07-05 12:02:56 +02:00
Paolo Bonzini 6edaa5307f KVM: remove kvm_guest_enter/exit wrappers
Use the functions from context_tracking.h directly.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:21 +02:00
David Hildenbrand a411edf132 KVM: s390: vsie: add module parameter "nested"
Let's be careful first and allow nested virtualization only if enabled
by the system administrator. In addition, user space still has to
explicitly enable it via SCLP features for it to work.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:47 +02:00
David Hildenbrand 5d3876a8bf KVM: s390: vsie: add indication for future features
We have certain SIE features that we cannot support for now.
Let's add these features, so user space can directly prepare to enable
them, so we don't have to update yet another component.

In addition, add a comment block, telling why it is for now not possible to
forward/enable these features.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:47 +02:00
David Hildenbrand 91473b487d KVM: s390: vsie: correctly set and handle guest TOD
Guest 2 sets up the epoch of guest 3 from his point of view. Therefore,
we have to add the guest 2 epoch to the guest 3 epoch. We also have to take
care of guest 2 epoch changes on STP syncs. This will work just fine by
also updating the guest 3 epoch when a vsie_block has been set for a VCPU.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:46 +02:00
David Hildenbrand b917ae573f KVM: s390: vsie: speed up VCPU external calls
Whenever a SIGP external call is injected via the SIGP external call
interpretation facility, the VCPU is not kicked. When a VCPU is currently
in the VSIE, the external call might not be processed immediately.

Therefore we have to provoke partial execution exceptions, which leads to a
kick of the VCPU and therefore also kick out of VSIE. This is done by
simulating the WAIT state. This bit has no other side effects.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:46 +02:00
David Hildenbrand 94a15de8fb KVM: s390: don't use CPUSTAT_WAIT to detect if a VCPU is idle
As we want to make use of CPUSTAT_WAIT also when a VCPU is not idle but
to force interception of external calls, let's check in the bitmap instead.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:45 +02:00
David Hildenbrand adbf16985c KVM: s390: vsie: speed up VCPU irq delivery when handling vsie
Whenever we want to wake up a VCPU (e.g. when injecting an IRQ), we
have to kick it out of vsie, so the request will be handled faster.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:44 +02:00
David Hildenbrand 1b7029bec1 KVM: s390: vsie: try to refault after a reported fault to g2
We can avoid one unneeded SIE entry after we reported a fault to g2.
Theoretically, g2 resolves the fault and we can create the shadow mapping
directly, instead of failing again when entering the SIE.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:44 +02:00
David Hildenbrand 7fd7f39daa KVM: s390: vsie: support IBS interpretation
We can easily enable ibs for guest 2, so he can use it for guest 3.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:43 +02:00
David Hildenbrand 13ee3f678b KVM: s390: vsie: support conditional-external-interception
We can easily enable cei for guest 2, so he can use it for guest 3.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:42 +02:00
David Hildenbrand 5630a8e82b KVM: s390: vsie: support intervention-bypass
We can easily enable intervention bypass for guest 2, so it can use it
for guest 3.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:42 +02:00
David Hildenbrand a1b7b9b286 KVM: s390: vsie: support guest-storage-limit-suppression
We can easily forward guest-storage-limit-suppression if available.

One thing to care about is keeping the prefix properly mapped when
gsls in toggled on/off or the mso changes in between. Therefore we better
remap the prefix on any mso changes just like we already do with the
prefix.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:41 +02:00
David Hildenbrand 77d18f6d47 KVM: s390: vsie: support guest-PER-enhancement
We can easily forward the guest-PER-enhancement facility to guest 2 if
available.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:40 +02:00
David Hildenbrand 0615a326e0 KVM: s390: vsie: support shared IPTE-interlock facility
As we forward the whole SCA provided by guest 2, we can directly forward
SIIF if available.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:40 +02:00
David Hildenbrand 19c439b564 KVM: s390: vsie: support 64-bit-SCAO
Let's provide the 64-bit-SCAO facility to guest 2, so he can set up a SCA
for guest 3 that has a 64 bit address. Please note that we already require
the 64 bit SCAO for our vsie implementation, in order to forward the SCA
directly (by pinning the page).

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:39 +02:00
David Hildenbrand 588438cba0 KVM: s390: vsie: support run-time-instrumentation
As soon as guest 2 is allowed to use run-time-instrumentation (indicated
via via STFLE), it can also enable it for guest 3.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:39 +02:00
David Hildenbrand c9bc1eabe5 KVM: s390: vsie: support vectory facility (SIMD)
As soon as guest 2 is allowed to use the vector facility (indicated via
STFLE), it can also enable it for guest 3. We have to take care of the
sattellite block that might be used when not relying on lazy vector
copying (not the case for KVM).

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:38 +02:00
David Hildenbrand 166ecb3d3c KVM: s390: vsie: support transactional execution
As soon as guest 2 is allowed to use transactional execution (indicated via
STFLE), he can also enable it for guest 3.

Active transactional execution requires also the second prefix page to be
mapped. If that page cannot be mapped, a validity icpt has to be presented
to the guest.

We have to take care of tx being toggled on/off, otherwise we might get
wrong prefix validity icpt.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:37 +02:00
David Hildenbrand bbeaa58b32 KVM: s390: vsie: support aes dea wrapping keys
As soon as message-security-assist extension 3 is enabled for guest 2,
we have to allow key wrapping for guest 3.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:37 +02:00
David Hildenbrand 66b630d5b7 KVM: s390: vsie: support STFLE interpretation
Issuing STFLE is extremely rare. Instead of copying 2k on every
VSIE call, let's do this lazily, when a guest 3 tries to execute
STFLE. We can setup the block and retry.

Unfortunately, we can't directly forward that facility list, as
we only have a 31 bit address for the facility list designation.
So let's use a DMA allocation for our vsie_page instead for now.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:36 +02:00
David Hildenbrand 4ceafa9027 KVM: s390: vsie: support host-protection-interruption
Introduced with ESOP, therefore available for the guest if it
is allowed to use ESOP.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:35 +02:00
David Hildenbrand 535ef81c6e KVM: s390: vsie: support edat1 / edat2
If guest 2 is allowed to use edat 1 / edat 2, it can also set it up for
guest 3, so let's properly check and forward the edat cpuflags.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:35 +02:00
David Hildenbrand 3573602b20 KVM: s390: vsie: support setting the ibc
As soon as we forward an ibc to guest 2 (indicated via
kvm->arch.model.ibc), he can also use it for guest 3. Let's properly round
the ibc up/down, so we avoid any potential validity icpts from the
underlying SIE, if it doesn't simply round the values.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:34 +02:00
David Hildenbrand 06d68a6c85 KVM: s390: vsie: optimize gmap prefix mapping
In order to not always map the prefix, we have to take care of certain
aspects that implicitly unmap the prefix:
- Changes to the prefix address
- Changes to MSO, because the HVA of the prefix is changed
- Changes of the gmap shadow (e.g. unshadowed, asce or edat changes)

By properly handling these cases, we can stop remapping the prefix when
there is no reason to do so.

This also allows us now to not acquire any gmap shadow locks when
rerunning the vsie and still having a valid gmap shadow.

Please note, to detect changing gmap shadows, we have to keep the reference
of the gmap shadow. The address of a gmap shadow does otherwise not
reliably indicate if the gmap shadow has changed (the memory chunk
could get reused).

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:34 +02:00
David Hildenbrand a3508fbe9d KVM: s390: vsie: initial support for nested virtualization
This patch adds basic support for nested virtualization on s390x, called
VSIE (virtual SIE) and allows it to be used by the guest if the necessary
facilities are supported by the hardware and enabled for the guest.

In order to make this work, we have to shadow the sie control block
provided by guest 2. In order to gain some performance, we have to
reuse the same shadow blocks as good as possible. For now, we allow
as many shadow blocks as we have VCPUs (that way, every VCPU can run the
VSIE concurrently).

We have to watch out for the prefix getting unmapped out of our shadow
gmap and properly get the VCPU out of VSIE in that case, to fault the
prefix pages back in. We use the PROG_REQUEST bit for that purpose.

This patch is based on an initial prototype by Tobias Elpelt.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-21 09:43:33 +02:00
David Hildenbrand 37d9df98b7 KVM: s390: backup the currently enabled gmap when scheduled out
Nested virtualization will have to enable own gmaps. Current code
would enable the wrong gmap whenever scheduled out and back in,
therefore resulting in the wrong gmap being enabled.

This patch reenables the last enabled gmap, therefore avoiding having to
touch vcpu->arch.gmap when enabling a different gmap.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:55:24 +02:00
David Hildenbrand 65d0b0d4bc KVM: s390: fast path for shadow gmaps in gmap notifier
The default kvm gmap notifier doesn't have to handle shadow gmaps.
So let's just directly exit in case we get notified about one.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:55:21 +02:00
David Hildenbrand 3218f7094b s390/mm: support real-space for gmap shadows
We can easily support real-space designation just like EDAT1 and EDAT2.
So guest2 can provide for guest3 an asce with the real-space control being
set.

We simply have to allocate the biggest page table possible and fake all
levels.

There is no protection to consider. If we exceed guest memory, vsie code
will inject an addressing exception (via program intercept). In the future,
we could limit the fake table level to the gmap page table.

As the top level page table can never go away, such gmap shadows will never
get unshadowed, we'll have to come up with another way to limit the number
of kept gmap shadows.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:55:02 +02:00
David Hildenbrand 1c65781b56 s390/mm: push rte protection down to shadow pte
Just like we already do with ste protection, let's take rte protection
into account. This way, the host pte doesn't have to be mapped writable.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:55:00 +02:00
David Hildenbrand 18b8980988 s390/mm: support EDAT2 for gmap shadows
If the guest is enabled for EDAT2, we can easily create shadows for
guest2 -> guest3 provided tables that make use of EDAT2.

If guest2 references a 2GB page, this memory looks consecutive for guest2,
but it does not have to be so for us. Therefore we have to create fake
segment and page tables.

This works just like EDAT1 support, so page tables are removed when the
parent table (r3t table entry) is changed.

We don't hve to care about:
- ACCF-Validity Control in RTTE
- Access-Control Bits in RTTE
- Fetch-Protection Bit in RTTE
- Common-Region Bit in RTTE

Just like for EDAT1, all bits might be dropped and there is no guaranteed
that they are active.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:56 +02:00
David Hildenbrand fd8d4e3ab6 s390/mm: support EDAT1 for gmap shadows
If the guest is enabled for EDAT1, we can easily create shadows for
guest2 -> guest3 provided tables that make use of EDAT1.

If guest2 references a 1MB page, this memory looks consecutive for guest2,
but it might not be so for us. Therefore we have to create fake page tables.

We can easily add that to our existing infrastructure. The invalidation
mechanism will make sure that fake page tables are removed when the parent
table (sgt table entry) is changed.

As EDAT1 also introduced protection on all page table levels, we have to
also shadow these correctly.

We don't have to care about:
- ACCF-Validity Control in STE
- Access-Control Bits in STE
- Fetch-Protection Bit in STE
- Common-Segment Bit in STE

As all bits might be dropped and there is no guaranteed that they are
active ("unpredictable whether the CPU uses these bits", "may be used").
Without using EDAT1 in the shadow ourselfes (STE-format control == 0),
simply shadowing these bits would not be enough. They would be ignored.

Please note that we are using the "fake" flag to make this look consistent
with further changes (EDAT2, real-space designation support) and don't let
the shadow functions handle fc=1 stes.

In the future, with huge pages in the host, gmap_shadow_pgt() could simply
try to map a huge host page if "fake" is set to one and indicate via return
value that no lower fake tables / shadow ptes are required.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:51 +02:00
David Hildenbrand 00fc062d53 s390/mm: push ste protection down to shadow pte
If a guest ste is read-only, it doesn't make sense to force the ptes in as
writable in the host. If the source page is read-only in the host, it won't
have to be made writable. Please note that if the source page is not
available, it will still be faulted in writable. This can be changed
internally later on.

If ste protection is removed, underlying shadow tables are also removed,
therefore this change does not affect the guest.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:45 +02:00
David Hildenbrand f4debb4090 s390/mm: take ipte_lock during shadow faults
Let's take the ipte_lock while working on guest 2 provided page table, just
like the other gaccess functions.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:40 +02:00
David Hildenbrand 7a6741576b s390/mm: protection exceptions are corrrectly shadowed
As gmap shadows contains correct protection permissions, protection
exceptons can directly be forwarded to guest 3. If we would encounter
a protection exception while faulting, the next guest 3 run will
automatically handle that for us.

Keep the dat_protection logic in place, as it will be helpful later.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:34 +02:00
David Hildenbrand e52f8b6112 s390/mm: take the mmap_sem in kvm_s390_shadow_fault()
Instead of doing it in the caller, let's just take the mmap_sem
in kvm_s390_shadow_fault(). By taking it as read, we allow parallel
faulting on shadow page tables, gmap shadow code is prepared for that.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:33 +02:00
David Hildenbrand a9d23e71d7 s390/mm: shadow pages with real guest requested protection
We really want to avoid manually handling protection for nested
virtualization. By shadowing pages with the protection the guest asked us
for, the SIE can handle most protection-related actions for us (e.g.
special handling for MVPG) and we can directly forward protection
exceptions to the guest.

PTEs will now always be shadowed with the correct _PAGE_PROTECT flag.
Unshadowing will take care of any guest changes to the parent PTE and
any host changes to the host PTE. If the host PTE doesn't have the
fitting access rights or is not available, we have to fix it up.

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:19 +02:00
Martin Schwidefsky aa17aa57cf s390/mm: add kvm shadow fault function
This patch introduces function kvm_s390_shadow_fault() used to resolve a
fault on a shadow gmap. This function will do validity checking and
build up the shadow page table hierarchy in order to fault in the
requested page into the shadow page table structure.

If an exception occurs while shadowing, guest 2 has to be notified about
it using either an exception or a program interrupt intercept. If
concurrent unshadowing occurres, this function will simply return with
-EAGAIN and the caller has to retry.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:54:12 +02:00
Martin Schwidefsky 6ea427bbbd s390/mm: add reference counter to gmap structure
Let's use a reference counter mechanism to control the lifetime of
gmap structures. This will be needed for further changes related to
gmap shadows.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:53:59 +02:00
Martin Schwidefsky b2d73b2a0a s390/mm: extended gmap pte notifier
The current gmap pte notifier forces a pte into to a read-write state.
If the pte is invalidated the gmap notifier is called to inform KVM
that the mapping will go away.

Extend this approach to allow read-write, read-only and no-access
as possible target states and call the pte notifier for any change
to the pte.

This mechanism is used to temporarily set specific access rights for
a pte without doing the heavy work of a true mprotect call.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:46:49 +02:00
Martin Schwidefsky 414d3b0749 s390/kvm: page table invalidation notifier
Pass an address range to the page table invalidation notifier
for KVM. This allows to notify changes that affect a larger
virtual memory area, e.g. for 1MB pages.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-20 09:46:48 +02:00
Paolo Bonzini a03825bbd0 KVM: s390: use kvm->created_vcpus
The new created_vcpus field avoids possible races between enabling
capabilities and creating VCPUs.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 10:07:37 +02:00
Paolo Bonzini f26ed98326 KVM: s390: Features and fixes for 4.8 part1
Four bigger things:
 1. The implementation of the STHYI opcode in the kernel. This is used
    in libraries like qclib [1] to provide enough information for a
    capacity and usage based software licence pricing. The STHYI content
    is defined by the related z/VM documentation [2]. Its data can be
    composed by accessing several other interfaces provided by LPAR or
    the machine. This information is partially sensitive or root-only
    so the kernel does the necessary filtering.
 2. Preparation for nested virtualization (VSIE). KVM should query the
    proper sclp interfaces for the availability of some features before
    using it. In the past we have been sloppy and simply assumed that
    several features are available. With this we should be able to handle
    most cases of a missing feature.
 3. CPU model interfaces extended by some additional features that are
    not covered by a facility bit in STFLE. For example all the crypto
    instructions of the coprocessor provide a query function. As reality
    tends to be more complex (e.g. export regulations might block some
    algorithms) we have to provide additional interfaces to query or
    set these non-stfle features.
 4. Several fixes and changes detected and fixed when doing 1-3.
 
 All features change base s390 code. All relevant patches have an ACK
 from the s390 or component maintainers.
 
 The next pull request for 4.8 (part2) will contain the implementation
 of VSIE.
 
 [1] http://www.ibm.com/developerworks/linux/linux390/qclib.html
 [2] https://www.ibm.com/support/knowledgecenter/SSB27U_6.3.0/com.ibm.zvm.v630.hcpb4/hcpb4sth.htm
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Merge tag 'kvm-s390-next-4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Features and fixes for 4.8 part1

Four bigger things:
1. The implementation of the STHYI opcode in the kernel. This is used
   in libraries like qclib [1] to provide enough information for a
   capacity and usage based software licence pricing. The STHYI content
   is defined by the related z/VM documentation [2]. Its data can be
   composed by accessing several other interfaces provided by LPAR or
   the machine. This information is partially sensitive or root-only
   so the kernel does the necessary filtering.
2. Preparation for nested virtualization (VSIE). KVM should query the
   proper sclp interfaces for the availability of some features before
   using it. In the past we have been sloppy and simply assumed that
   several features are available. With this we should be able to handle
   most cases of a missing feature.
3. CPU model interfaces extended by some additional features that are
   not covered by a facility bit in STFLE. For example all the crypto
   instructions of the coprocessor provide a query function. As reality
   tends to be more complex (e.g. export regulations might block some
   algorithms) we have to provide additional interfaces to query or
   set these non-stfle features.
4. Several fixes and changes detected and fixed when doing 1-3.

All features change base s390 code. All relevant patches have an ACK
from the s390 or component maintainers.

The next pull request for 4.8 (part2) will contain the implementation
of VSIE.

[1] http://www.ibm.com/developerworks/linux/linux390/qclib.html
[2] https://www.ibm.com/support/knowledgecenter/SSB27U_6.3.0/com.ibm.zvm.v630.hcpb4/hcpb4sth.htm
2016-06-15 09:21:46 +02:00
Andrea Gelmini 960cb306e6 KVM: S390: Fix typo
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14 11:16:27 +02:00
Martin Schwidefsky fd5ada0403 s390/time: remove ETR support
The External-Time-Reference (ETR) clock synchronization interface has
been superseded by Server-Time-Protocol (STP). Remove the outdated
ETR interface.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13 15:58:21 +02:00
David Hildenbrand a7e19ab55f KVM: s390: handle missing storage-key facility
Without the storage-key facility, SIE won't interpret SSKE, ISKE and
RRBE for us. So let's add proper interception handlers that will be called
if lazy sske cannot be enabled.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:31 +02:00
David Hildenbrand 11ddcd41bc KVM: s390: trace and count all skey intercepts
Let's trace and count all skey handling operations, even if lazy skey
handling was already activated. Also, don't enable lazy skey handling if
anything went wrong while enabling skey handling for the SIE.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:31 +02:00
David Hildenbrand 695be0e7a2 KVM: s390: pfmf: handle address overflows
In theory, end could always end up being < start, if overflowing to 0.
Although very unlikely for now, let's just fix it.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:30 +02:00
David Hildenbrand 1824c723ac KVM: s390: pfmf: support conditional-sske facility
We already indicate that facility but don't implement it in our pfmf
interception handler. Let's add a new storage key handling function for
conditionally setting the guest storage key.

As we will reuse this function later on, let's directly implement returning
the old key via parameter and indicating if any change happened via rc.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:30 +02:00
David Hildenbrand 2c26d1d23a KVM: s390: pfmf: take care of amode when setting reg2
Depending on the addressing mode, we must not overwrite bit 0-31 of the
register. In addition, 24 bit and 31 bit have to set certain bits to 0,
which is guaranteed by converting the end address to an effective
address.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:29 +02:00
David Hildenbrand 9a68f0af8c KVM: s390: pfmf: MR and MC are ignored without CSSKE
These two bits are simply ignored when the conditional-SSKE facility is
not installed.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:29 +02:00
David Hildenbrand 6164a2e90a KVM: s390: pfmf: fix end address calculation
The current calculation is wrong if absolute != real address. Let's just
calculate the start address for 4k frames upfront. Otherwise, the
calculated end address will be wrong, resulting in wrong memory
location/storage keys getting touched.

To keep low-address protection working (using the effective address),
we have to move the check.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:28 +02:00
David Hildenbrand fe69eabf8d KVM: s390: storage keys fit into a char
No need to convert the storage key into an unsigned long, the target
function expects a char as argument.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:28 +02:00
David Hildenbrand 154c8c19c3 s390/mm: return key via pointer in get_guest_storage_key
Let's just split returning the key and reporting errors. This makes calling
code easier and avoids bugs as happened already.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:28 +02:00
Martin Schwidefsky d3ed1ceeac s390/mm: set and get guest storage key mmap locking
Move the mmap semaphore locking out of set_guest_storage_key
and get_guest_storage_key. This makes the two functions more
like the other ptep_xxx operations and allows to avoid repeated
semaphore operations if multiple keys are read or written.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:27 +02:00
Christian Borntraeger dcc98ea614 KVM: s390: fixup I/O interrupt traces
We currently have two issues with the I/O  interrupt injection logging:
1. All QEMU versions up to 2.6 have a wrong encoding of device numbers
etc for the I/O interrupt type, so the inject VM_EVENT will have wrong
data. Let's fix this by using the interrupt parameters and not the
interrupt type number.
2. We only log in kvm_s390_inject_vm, but not when coming from
kvm_s390_reinject_io_int or from flic. Let's move the logging to the
common __inject_io function.

We also enhance the logging for delivery to match the data.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-06-10 12:07:26 +02:00
Christian Borntraeger 1bb78d161f KVM: s390: provide logging for diagnose 0x500
We might need to debug some virtio things, so better have diagnose 500
logged.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-06-10 12:07:26 +02:00
David Hildenbrand f597d24eee KVM: s390: turn on tx even without ctx
Constrained transactional execution is an addon of transactional execution.

Let's enable the assist also if only TX is enabled for the guest.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:25 +02:00
David Hildenbrand bdab09f3d8 KVM: s390: enable host-protection-interruption only with ESOP
host-protection-interruption control was introduced with ESOP. So let's
enable it only if we have ESOP and add an explanatory comment why
we can live without it.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:25 +02:00
David Hildenbrand 09a400e78e KVM: s390: enable ibs only if available
Let's enable interlock-and-broadcast suppression only if the facility is
actually available.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:24 +02:00
David Hildenbrand 873b425e4c KVM: s390: enable PFMFI only if available
Let's enable interpretation of PFMFI only if the facility is
actually available. Emulation code still works in case the guest is
offered EDAT-1.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:23 +02:00
David Hildenbrand 48ee7d3a7f KVM: s390: enable cei only if available
Let's only enable conditional-external-interruption if the facility is
actually available.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:23 +02:00
David Hildenbrand 11ad65b79e KVM: s390: enable ib only if available
Let's enable intervention bypass only if the facility is acutally
available.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:22 +02:00
David Hildenbrand efed110446 KVM: s390: handle missing guest-storage-limit-suppression
If guest-storage-limit-suppression is not available, we would for now
have a valid guest address space with size 0. So let's simply set the
origin to 0 and the limit to hamax.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:21 +02:00
David Hildenbrand f9cbd9b025 KVM: s390: provide CMMA attributes only if available
Let's not provide the device attribute for cmma enabling and clearing
if the hardware doesn't support it.

This also helps getting rid of the undocumented return value "-EINVAL"
in case CMMA is not available when trying to enable it.

Also properly document the meaning of -EINVAL for CMMA clearing.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:20 +02:00
David Hildenbrand c24cc9c8a6 KVM: s390: enable CMMA if the interpration is available
Now that we can detect if collaborative-memory-management interpretation
is available, replace the heuristic by a real hardware detection.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:19 +02:00
David Hildenbrand 89b5b4de33 KVM: s390: guestdbg: signal missing hardware support
Without guest-PER enhancement, we can't provide any debugging support.
Therefore act like kernel support is missing.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:18 +02:00
David Hildenbrand 76a6dd7241 KVM: s390: handle missing 64-bit-SCAO facility
Without that facility, we may only use scaol. So fallback
to DMA allocation in that case, so we won't overwrite random memory
via the SIE.

Also disallow ESCA, so we don't have to handle that allocation case.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:18 +02:00
David Hildenbrand 0a763c780b KVM: s390: interface to query and configure cpu subfunctions
We have certain instructions that indicate available subfunctions via
a query subfunction (crypto functions and ptff), or via a test bit
function (plo).

By exposing these "subfunction blocks" to user space, we allow user space
to
1) query available subfunctions and make sure subfunctions won't get lost
   during migration - e.g. properly indicate them via a CPU model
2) change the subfunctions to be reported to the guest (even adding
   unavailable ones)

This mechanism works just like the way we indicate the stfl(e) list to
user space.

This way, user space could even emulate some subfunctions in QEMU in the
future. If this is ever applicable, we have to make sure later on, that
unsupported subfunctions result in an intercept to QEMU.

Please note that support to indicate them to the guest is still missing
and requires hardware support. Usually, the IBC takes already care of these
subfunctions for migration safety. QEMU should make sure to always set
these bits properly according to the machine generation to be emulated.

Available subfunctions are only valid in combination with STFLE bits
retrieved via KVM_S390_VM_CPU_MACHINE and enabled via
KVM_S390_VM_CPU_PROCESSOR. If the applicable bits are available, the
indicated subfunctions are guaranteed to be correct.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:17 +02:00
David Hildenbrand bcfa01d787 KVM: s390: gaccess: convert get_vcpu_asce()
Let's use our new function for preparing translation exceptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:16 +02:00
David Hildenbrand cde0dcfb5d KVM: s390: gaccess: convert guest_page_range()
Let's use our new function for preparing translation exceptions. As we will
need the correct ar, let's pass that to guest_page_range().

This will also make sure that the guest address is stored in the tec
for applicable excptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:15 +02:00
David Hildenbrand fbcb7d5157 KVM: s390: gaccess: convert guest_translate_address()
Let's use our new function for preparing translation exceptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:15 +02:00
David Hildenbrand 3e3c67f6a3 KVM: s390: gaccess: convert kvm_s390_check_low_addr_prot_real()
Let's use our new function for preparing translation exceptions.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:15 +02:00
David Hildenbrand d03193de30 KVM: s390: gaccess: function for preparing translation exceptions
Let's provide a function trans_exc() that can be used for handling
preparation of translation exceptions on a central basis. We will use
that function to replace existing code in gaccess.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:14 +02:00
David Hildenbrand 6167375b55 KVM: s390: gaccess: store guest address on ALC prot exceptions
Let's pass the effective guest address to get_vcpu_asce(), so we
can properly set the guest address in case we inject an ALC protection
exception.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:14 +02:00
David Hildenbrand 22be5a1331 KVM: s390: forward ESOP if available
ESOP guarantees that during a protection exception, bit 61 of real location
168-175 will only be set to 1 if it was because of ALCP or DATP. If the
exception is due to LAP or KCP, the bit will always be set to 0.

The old SOP definition allowed bit 61 to be unpredictable in case of LAP
or KCP in some conditions. So ESOP replaces this unpredictability by
a guarantee.

Therefore, we can directly forward ESOP if it is available on our machine.
We don't have to do anything when ESOP is disabled - the guest will simply
expect unpredictable values. Our guest access functions are already
handling ESOP properly.

Please note that future functionality in KVM will require knowledge about
ESOP being enabled for a guest or not.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:13 +02:00
David Hildenbrand 15c9705f0c KVM: s390: interface to query and configure cpu features
For now, we only have an interface to query and configure facilities
indicated via STFL(E). However, we also have features indicated via
SCLP, that have to be indicated to the guest by user space and usually
require KVM support.

This patch allows user space to query and configure available cpu features
for the guest.

Please note that disabling a feature doesn't necessarily mean that it is
completely disabled (e.g. ESOP is mostly handled by the SIE). We will try
our best to disable it.

Most features (e.g. SCLP) can't directly be forwarded, as most of them need
in addition to hardware support, support in KVM. As we later on want to
turn these features in KVM explicitly on/off (to simulate different
behavior), we have to filter all features provided by the hardware and
make them configurable.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:13 +02:00
Alexander Yarygin c1778e5157 KVM: s390: Add mnemonic print to kvm_s390_intercept_prog
We have a table of mnemonic names for intercepted program
interruptions, let's print readable name of the interruption in the
kvm_s390_intercept_prog trace event.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:13 +02:00
Janosch Frank 7d0a5e6241 KVM: s390: Limit sthyi execution
Store hypervisor information is a valid instruction not only in
supervisor state but also in problem state, i.e. the guest's
userspace. Its execution is not only computational and memory
intensive, but also has to get hold of the ipte lock to write to the
guest's memory.

This lock is not intended to be held often and long, especially not
from the untrusted guest userspace. Therefore we apply rate limiting
of sthyi executions per VM.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Acked-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:12 +02:00
Janosch Frank 95ca2cb579 KVM: s390: Add sthyi emulation
Store Hypervisor Information is an emulated z/VM instruction that
provides a guest with basic information about the layers it is running
on. This includes information about the cpu configuration of both the
machine and the lpar, as well as their names, machine model and
machine type. This information enables an application to determine the
maximum capacity of CPs and IFLs available to software.

The instruction is available whenever the facility bit 74 is set,
otherwise executing it results in an operation exception.

It is important to check the validity flags in the sections before
using data from any structure member. It is not guaranteed that all
members will be valid on all machines / machine configurations.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:12 +02:00
Janosch Frank a011eeb2a3 KVM: s390: Add operation exception interception handler
This commit introduces code that handles operation exception
interceptions. With this handler we can emulate instructions by using
illegal opcodes.

Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 12:07:11 +02:00
Alexander Yarygin 9ec6de1923 KVM: s390: Add stats for PEI events
Add partial execution intercepted events in kvm_stats_debugfs.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 10:24:24 +02:00
David Hildenbrand 0487c44d1e KVM: s390: ignore IBC if zero
Looks like we forgot about the special IBC value of 0 meaning "no IBC".
Let's fix that, otherwise it gets rounded up and suddenly an IBC is active
with the lowest possible machine.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Fixes: commit 053dd2308d ("KVM: s390: force ibc into valid range")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-06-10 10:21:38 +02:00
Christian Borntraeger 3491caf275 KVM: halt_polling: provide a way to qualify wakeups during poll
Some wakeups should not be considered a sucessful poll. For example on
s390 I/O interrupts are usually floating, which means that _ALL_ CPUs
would be considered runnable - letting all vCPUs poll all the time for
transactional like workload, even if one vCPU would be enough.
This can result in huge CPU usage for large guests.
This patch lets architectures provide a way to qualify wakeups if they
should be considered a good/bad wakeups in regard to polls.

For s390 the implementation will fence of halt polling for anything but
known good, single vCPU events. The s390 implementation for floating
interrupts does a wakeup for one vCPU, but the interrupt will be delivered
by whatever CPU checks first for a pending interrupt. We prefer the
woken up CPU by marking the poll of this CPU as "good" poll.
This code will also mark several other wakeup reasons like IPI or
expired timers as "good". This will of course also mark some events as
not sucessful. As  KVM on z runs always as a 2nd level hypervisor,
we prefer to not poll, unless we are really sure, though.

This patch successfully limits the CPU usage for cases like uperf 1byte
transactional ping pong workload or wakeup heavy workload like OLTP
while still providing a proper speedup.

This also introduced a new vcpu stat "halt_poll_no_tuning" that marks
wakeups that are considered not good for polling.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Radim Krčmář <rkrcmar@redhat.com> (for an earlier version)
Cc: David Matlack <dmatlack@google.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
[Rename config symbol. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-13 17:29:23 +02:00
Alexander Yarygin 60a37709ce KVM: s390: Populate mask of non-hypervisor managed facility bits
When a guest is initializing, KVM provides facility bits that can be
successfully used by the guest. It's done by applying
kvm_s390_fac_list_mask mask on host facility bits stored by the STFLE
instruction. Facility bits can be one of two kinds: it's either a
hypervisor managed bit or non-hypervisor managed.

The hardware provides information which bits need special handling.
Let's automatically passthrough to guests new facility bits, that
don't require hypervisor support.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 13:33:59 +02:00
Alexander Yarygin ed8dda0bf7 KVM: s390: Enable all facility bits that are known good for passthrough
Some facility bits are in a range that is defined to be "ok for guests
without any necessary hypervisor changes". Enable those bits.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 13:33:58 +02:00
David Hildenbrand 053dd2308d KVM: s390: force ibc into valid range
Some hardware variants will round the ibc value up/down themselves,
others will report a validity intercept. Let's always round it up/down.

This patch will also make sure that the ibc is set to 0 in case we don't
have ibc support (lowest_ibc == 0).

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 13:33:57 +02:00
David Hildenbrand 9bb0ec0997 KVM: s390: cleanup cpuid handling
We only have one cpuid for all VCPUs, so let's directly use the one in the
cpu model. Also always store it directly as u64, no need for struct cpuid.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 13:33:57 +02:00
David Hildenbrand bd50e8ec8f KVM: s390: enable SRS only if enabled for the guest
If we don't have SIGP SENSE RUNNING STATUS enabled for the guest, let's
not enable interpretation so we can correctly report an invalid order.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 13:33:55 +02:00
David Hildenbrand d6af0b491b KVM: s390: enable PFMFI only if guest has EDAT1
Only enable PFMF interpretation if the necessary facility (EDAT1) is
available, otherwise the pfmf handler in priv.c will inject an exception

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 13:33:02 +02:00
David Hildenbrand edc5b05566 KVM: s390: support NQ only if the facility is enabled for the guest
While we can not fully fence of the Nonquiescing Key-Setting facility,
we should as try our best to hide it.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-04 10:57:39 +02:00
David Hildenbrand 4a5e7e381f KVM: s390: cmma: don't check entry content
We should never inject an exception after we manually rewound the PSW
(to retry the ESSA instruction in this case). This will mess up the PSW.
So this never worked and therefore never really triggered.

Looking at the details, we don't even have to perform any validity checks.
1. Bits 52-63 of an entry are stored as 0 by the hardware.
2. We are dealing with absolute addresses but only check for the prefix
   starting at address 0. This isn't correct and doesn't make much sense,
   cpus could still zap the prefix of other cpus. But as prefix pages
   cannot be swapped out without a notifier being called for the affected
   VCPU, a zap can never remove a protected prefix.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-04 10:57:38 +02:00
Halil Pasic 6d28f789bf KVM: s390: add clear I/O irq operation for FLIC
Introduce a FLIC operation for clearing I/O interrupts for a subchannel.

Rationale: According to the platform specification, pending I/O
interruption requests have to be revoked in certain situations. For
instance, according to the Principles of Operation (page 17-27), a
subchannel put into the installed parameters initialized state is in the
same state as after an I/O system reset (just parameters possibly changed).
This implies that any I/O interrupts for that subchannel are no longer
pending (as I/O system resets clear I/O interrupts). Therefore, we need an
interface to clear pending I/O interrupts.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-04-20 14:27:32 +02:00
Halil Pasic 4f1298584e KVM: s390: implement has_attr for FLIC
HAS_ATTR is useful for determining the supported attributes; let's
implement it.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-04-20 14:27:32 +02:00
Linus Torvalds 72aafdf01d Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:

 - Add the CPU id for the new z13s machine

 - Add a s390 specific XOR template for RAID-5 checksumming based on the
   XC instruction.  Remove all other alternatives, XC is always faster

 - The merge of our four different stack tracers into a single one

 - Tidy up the code related to page tables, several large inline
   functions are now out-of-line.  Bloat-o-meter reports ~11K text size
   reduction

 - A binary interface for the priviledged CLP instruction to retrieve
   the hardware view of the installed PCI functions

 - Improvements for the dasd format code

 - Bug fixes and cleanups

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits)
  s390/pci: enforce fmb page boundary rule
  s390: fix floating pointer register corruption (again)
  s390/cpumf: add missing lpp magic initialization
  s390: Fix misspellings in comments
  s390/mm: split arch/s390/mm/pgtable.c
  s390/mm: uninline pmdp_xxx functions from pgtable.h
  s390/mm: uninline ptep_xxx functions from pgtable.h
  s390/pci: add ioctl interface for CLP
  s390: Use pr_warn instead of pr_warning
  s390/dasd: remove casts to dasd_*_private
  s390/dasd: Refactor dasd format functions
  s390/dasd: Simplify code in format logic
  s390/dasd: Improve dasd format code
  s390/percpu: remove this_cpu_cmpxchg_double_4
  s390/cpumf: Improve guest detection heuristics
  s390/fault: merge report_user_fault implementations
  s390/dis: use correct escape sequence for '%' character
  s390/kvm: simplify set_guest_storage_key
  s390/oprofile: add z13/z13s model numbers
  s390: add z13s model number to z13 elf platform
  ...
2016-03-16 10:47:45 -07:00
Linus Torvalds 10dc374766 One of the largest releases for KVM... Hardly any generic improvement,
but lots of architecture-specific changes.
 
 * ARM:
 - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
 - PMU support for guests
 - 32bit world switch rewritten in C
 - various optimizations to the vgic save/restore code.
 
 * PPC:
 - enabled KVM-VFIO integration ("VFIO device")
 - optimizations to speed up IPIs between vcpus
 - in-kernel handling of IOMMU hypercalls
 - support for dynamic DMA windows (DDW).
 
 * s390:
 - provide the floating point registers via sync regs;
 - separated instruction vs. data accesses
 - dirty log improvements for huge guests
 - bugfixes and documentation improvements.
 
 * x86:
 - Hyper-V VMBus hypercall userspace exit
 - alternative implementation of lowest-priority interrupts using vector
 hashing (for better VT-d posted interrupt support)
 - fixed guest debugging with nested virtualizations
 - improved interrupt tracking in the in-kernel IOAPIC
 - generic infrastructure for tracking writes to guest memory---currently
 its only use is to speedup the legacy shadow paging (pre-EPT) case, but
 in the future it will be used for virtual GPUs as well
 - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "One of the largest releases for KVM...  Hardly any generic
  changes, but lots of architecture-specific updates.

  ARM:
   - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
   - PMU support for guests
   - 32bit world switch rewritten in C
   - various optimizations to the vgic save/restore code.

  PPC:
   - enabled KVM-VFIO integration ("VFIO device")
   - optimizations to speed up IPIs between vcpus
   - in-kernel handling of IOMMU hypercalls
   - support for dynamic DMA windows (DDW).

  s390:
   - provide the floating point registers via sync regs;
   - separated instruction vs.  data accesses
   - dirty log improvements for huge guests
   - bugfixes and documentation improvements.

  x86:
   - Hyper-V VMBus hypercall userspace exit
   - alternative implementation of lowest-priority interrupts using
     vector hashing (for better VT-d posted interrupt support)
   - fixed guest debugging with nested virtualizations
   - improved interrupt tracking in the in-kernel IOAPIC
   - generic infrastructure for tracking writes to guest
     memory - currently its only use is to speedup the legacy shadow
     paging (pre-EPT) case, but in the future it will be used for
     virtual GPUs as well
   - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits)
  KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch
  KVM: x86: disable MPX if host did not enable MPX XSAVE features
  arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit
  arm64: KVM: vgic-v3: Reset LRs at boot time
  arm64: KVM: vgic-v3: Do not save an LR known to be empty
  arm64: KVM: vgic-v3: Save maintenance interrupt state only if required
  arm64: KVM: vgic-v3: Avoid accessing ICH registers
  KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit
  KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit
  KVM: arm/arm64: vgic-v2: Reset LRs at boot time
  KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty
  KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function
  KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required
  KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
  KVM: s390: allocate only one DMA page per VM
  KVM: s390: enable STFLE interpretation only if enabled for the guest
  KVM: s390: wake up when the VCPU cpu timer expires
  KVM: s390: step the VCPU timer while in enabled wait
  KVM: s390: protect VCPU cpu timer with a seqcount
  KVM: s390: step VCPU cpu timer during kvm_run ioctl
  ...
2016-03-16 09:55:35 -07:00
Linus Torvalds d4e796152a Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle are:

   - Make schedstats a runtime tunable (disabled by default) and
     optimize it via static keys.

     As most distributions enable CONFIG_SCHEDSTATS=y due to its
     instrumentation value, this is a nice performance enhancement.
     (Mel Gorman)

   - Implement 'simple waitqueues' (swait): these are just pure
     waitqueues without any of the more complex features of full-blown
     waitqueues (callbacks, wake flags, wake keys, etc.).  Simple
     waitqueues have less memory overhead and are faster.

     Use simple waitqueues in the RCU code (in 4 different places) and
     for handling KVM vCPU wakeups.

     (Peter Zijlstra, Daniel Wagner, Thomas Gleixner, Paul Gortmaker,
     Marcelo Tosatti)

   - sched/numa enhancements (Rik van Riel)

   - NOHZ performance enhancements (Rik van Riel)

   - Various sched/deadline enhancements (Steven Rostedt)

   - Various fixes (Peter Zijlstra)

   - ... and a number of other fixes, cleanups and smaller enhancements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
  sched/cputime: Fix steal_account_process_tick() to always return jiffies
  sched/deadline: Remove dl_new from struct sched_dl_entity
  Revert "kbuild: Add option to turn incompatible pointer check into error"
  sched/deadline: Remove superfluous call to switched_to_dl()
  sched/debug: Fix preempt_disable_ip recording for preempt_disable()
  sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity
  time, acct: Drop irq save & restore from __acct_update_integrals()
  acct, time: Change indentation in __acct_update_integrals()
  sched, time: Remove non-power-of-two divides from __acct_update_integrals()
  sched/rt: Kick RT bandwidth timer immediately on start up
  sched/debug: Add deadline scheduler bandwidth ratio to /proc/sched_debug
  sched/debug: Move sched_domain_sysctl to debug.c
  sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c
  sched/rt: Fix PI handling vs. sched_setscheduler()
  sched/core: Remove duplicated sched_group_set_shares() prototype
  sched/fair: Consolidate nohz CPU load update code
  sched/fair: Avoid using decay_load_missed() with a negative value
  sched/deadline: Always calculate end of period on sched_yield()
  sched/cgroup: Fix cgroup entity load tracking tear-down
  rcu: Use simple wait queues where possible in rcutree
  ...
2016-03-14 19:14:06 -07:00
Adam Buchbinder 7eb792bf7c s390: Fix misspellings in comments
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 15:00:17 +01:00
Martin Schwidefsky 1e133ab296 s390/mm: split arch/s390/mm/pgtable.c
The pgtable.c file is quite big, before it grows any larger split it
into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related
header definitions into the new gmap.h header and all of the pgste
helpers from pgtable.h to pgtable.c.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 15:00:15 +01:00
Martin Schwidefsky ebde765c0e s390/mm: uninline ptep_xxx functions from pgtable.h
The code in the various ptep_xxx functions has grown quite large,
consolidate them to four out-of-line functions:
  ptep_xchg_direct to exchange a pte with another with immediate flushing
  ptep_xchg_lazy to exchange a pte with another in a batched update
  ptep_modify_prot_start to begin a protection flags update
  ptep_modify_prot_commit to commit a protection flags update

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 15:00:12 +01:00
David Hildenbrand c54f0d6ae0 KVM: s390: allocate only one DMA page per VM
We can fit the 2k for the STFLE interpretation and the crypto
control block into one DMA page. As we now only have to allocate
one DMA page, we can clean up the code a bit.

As a nice side effect, this also fixes a problem with crycbd alignment in
case special allocation debug options are enabled, debugged by Sascha
Silbe.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:54 +01:00
David Hildenbrand 80bc79dc0b KVM: s390: enable STFLE interpretation only if enabled for the guest
Not setting the facility list designation disables STFLE interpretation,
this is what we want if the guest was told to not have it.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:54 +01:00
David Hildenbrand b3c17f10fa KVM: s390: wake up when the VCPU cpu timer expires
When the VCPU cpu timer expires, we have to wake up just like when the ckc
triggers. For now, setting up a cpu timer in the guest and going into
enabled wait will never lead to a wakeup. This patch fixes this problem.
Just as for the ckc, we have to take care of waking up too early. We
have to recalculate the sleep time and go back to sleep.

Please note that the timer callback calls kvm_s390_get_cpu_timer() from
interrupt context. As the timer is canceled when leaving handle_wait(),
and we don't do any VCPU cpu timer writes/updates in that function, we can
be sure that we will never try to read the VCPU cpu timer from the same cpu
that is currentyl updating the timer (deadlock).

Reported-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Tested-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:53 +01:00
David Hildenbrand 5ebda31686 KVM: s390: step the VCPU timer while in enabled wait
The cpu timer is a mean to measure task execution time. We want
to account everything for a VCPU for which it is responsible. Therefore,
if the VCPU wants to sleep, it shall be accounted for it.

We can easily get this done by not disabling cpu timer accounting when
scheduled out while sleeping because of enabled wait.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:53 +01:00
David Hildenbrand 9c23a1318e KVM: s390: protect VCPU cpu timer with a seqcount
For now, only the owning VCPU thread (that has loaded the VCPU) can get a
consistent cpu timer value when calculating the delta. However, other
threads might also be interested in a more recent, consistent value. Of
special interest will be the timer callback of a VCPU that executes without
having the VCPU loaded and could run in parallel with the VCPU thread.

The cpu timer has a nice property: it is only updated by the owning VCPU
thread. And speaking about accounting, a consistent value can only be
calculated by looking at cputm_start and the cpu timer itself in
one shot, otherwise the result might be wrong.

As we only have one writing thread at a time (owning VCPU thread), we can
use a seqcount instead of a seqlock and retry if the VCPU refreshed its
cpu timer. This avoids any heavy locking and only introduces a counter
update/check plus a handful of smp_wmb().

The owning VCPU thread should never have to retry on reads, and also for
other threads this might be a very rare scenario.

Please note that we have to use the raw_* variants for locking the seqcount
as lockdep will produce false warnings otherwise. The rq->lock held during
vcpu_load/put is also acquired from hardirq context. Lockdep cannot know
that we avoid potential deadlocks by disabling preemption and thereby
disable concurrent write locking attempts (via vcpu_put/load).

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:53 +01:00
David Hildenbrand db0758b297 KVM: s390: step VCPU cpu timer during kvm_run ioctl
Architecturally we should only provide steal time if we are scheduled
away, and not if the host interprets a guest exit. We have to step
the guest CPU timer in these cases.

In the first shot, we will step the VCPU timer only during the kvm_run
ioctl. Therefore all time spent e.g. in interception handlers or on irq
delivery will be accounted for that VCPU.

We have to take care of a few special cases:
- Other VCPUs can test for pending irqs. We can only report a consistent
  value for the VCPU thread itself when adding the delta.
- We have to take care of STP sync, therefore we have to extend
  kvm_clock_sync() and disable preemption accordingly
- During any call to disable/enable/start/stop we could get premeempted
  and therefore get start/stop calls. Therefore we have to make sure we
  don't get into an inconsistent state.

Whenever a VCPU is scheduled out, sleeping, in user space or just about
to enter the SIE, the guest cpu timer isn't stepped.

Please note that all primitives are prepared to be called from both
environments (cpu timer accounting enabled or not), although not completely
used in this patch yet (e.g. kvm_s390_set_cpu_timer() will never be called
while cpu timer accounting is enabled).

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:52 +01:00
David Hildenbrand 4287f247f6 KVM: s390: abstract access to the VCPU cpu timer
We want to manually step the cpu timer in certain scenarios in the future.
Let's abstract any access to the cpu timer, so we can hide the complexity
internally.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:52 +01:00
David Hildenbrand 01a745ac8b KVM: s390: store cpu id in vcpu->cpu when scheduled in
By storing the cpu id, we have a way to verify if the current cpu is
owning a VCPU.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:51 +01:00
David Hildenbrand 9522b37f5a KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUS
With MACHINE_HAS_VX, we convert the floating point registers from the
vector registeres when storing the status. For other VCPUs, these are
stored to vcpu->run->s.regs.vrs, but we are using current->thread.fpu.vxrs,
which resolves to the currently loaded VCPU.

So kvm_s390_store_status_unloaded() currently writes the wrong floating
point registers (converted from the vector registers) when called from
another VCPU on a z13.

This is only the case for old user space not handling SIGP STORE STATUS and
SIGP STOP AND STORE STATUS, but relying on the kernel implementation. All
other calls come from the loaded VCPU via kvm_s390_store_status().

Fixes: 9abc2a08a7 (KVM: s390: fix memory overwrites when vx is disabled)
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-08 12:47:01 +01:00
Marcelo Tosatti 8577370fb0 KVM: Use simple waitqueue for vcpu->wq
The problem:

On -rt, an emulated LAPIC timer instances has the following path:

1) hard interrupt
2) ksoftirqd is scheduled
3) ksoftirqd wakes up vcpu thread
4) vcpu thread is scheduled

This extra context switch introduces unnecessary latency in the
LAPIC path for a KVM guest.

The solution:

Allow waking up vcpu thread from hardirq context,
thus avoiding the need for ksoftirqd to be scheduled.

Normal waitqueues make use of spinlocks, which on -RT
are sleepable locks. Therefore, waking up a waitqueue
waiter involves locking a sleeping lock, which
is not allowed from hard interrupt context.

cyclictest command line:

This patch reduces the average latency in my tests from 14us to 11us.

Daniel writes:
Paolo asked for numbers from kvm-unit-tests/tscdeadline_latency
benchmark on mainline. The test was run 1000 times on
tip/sched/core 4.4.0-rc8-01134-g0905f04:

  ./x86-run x86/tscdeadline_latency.flat -cpu host

with idle=poll.

The test seems not to deliver really stable numbers though most of
them are smaller. Paolo write:

"Anything above ~10000 cycles means that the host went to C1 or
lower---the number means more or less nothing in that case.

The mean shows an improvement indeed."

Before:

               min             max         mean           std
count  1000.000000     1000.000000  1000.000000   1000.000000
mean   5162.596000  2019270.084000  5824.491541  20681.645558
std      75.431231   622607.723969    89.575700   6492.272062
min    4466.000000    23928.000000  5537.926500    585.864966
25%    5163.000000  1613252.750000  5790.132275  16683.745433
50%    5175.000000  2281919.000000  5834.654000  23151.990026
75%    5190.000000  2382865.750000  5861.412950  24148.206168
max    5228.000000  4175158.000000  6254.827300  46481.048691

After
               min            max         mean           std
count  1000.000000     1000.00000  1000.000000   1000.000000
mean   5143.511000  2076886.10300  5813.312474  21207.357565
std      77.668322   610413.09583    86.541500   6331.915127
min    4427.000000    25103.00000  5529.756600    559.187707
25%    5148.000000  1691272.75000  5784.889825  17473.518244
50%    5160.000000  2308328.50000  5832.025000  23464.837068
75%    5172.000000  2393037.75000  5853.177675  24223.969976
max    5222.000000  3922458.00000  6186.720500  42520.379830

[Patch was originaly based on the swait implementation found in the -rt
 tree. Daniel ported it to mainline's version and gathered the
 benchmark numbers for tscdeadline_latency test.]

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-rt-users@vger.kernel.org
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1455871601-27484-4-git-send-email-wagi@monom.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-02-25 11:27:16 +01:00
Christian Borntraeger 1763f8d09d KVM: s390: bail out early on fatal signal in dirty logging
A KVM_GET_DIRTY_LOG ioctl might take a long time.
This can result in fatal signals seemingly being ignored.
Lets bail out during the dirty bit sync, if a fatal signal
is pending.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:57 +01:00
Christian Borntraeger 70c88a00fb KVM: s390: do not block CPU on dirty logging
When doing dirty logging on huge guests (e.g.600GB) we sometimes
get rcu stall timeouts with backtraces like

[ 2753.194083] ([<0000000000112fb2>] show_trace+0x12a/0x130)
[ 2753.194092]  [<0000000000113024>] show_stack+0x6c/0xe8
[ 2753.194094]  [<00000000001ee6a8>] rcu_pending+0x358/0xa48
[ 2753.194099]  [<00000000001f20cc>] rcu_check_callbacks+0x84/0x168
[ 2753.194102]  [<0000000000167654>] update_process_times+0x54/0x80
[ 2753.194107]  [<00000000001bdb5c>] tick_sched_handle.isra.16+0x4c/0x60
[ 2753.194113]  [<00000000001bdbd8>] tick_sched_timer+0x68/0x90
[ 2753.194115]  [<0000000000182a88>] __run_hrtimer+0x88/0x1f8
[ 2753.194119]  [<00000000001838ba>] hrtimer_interrupt+0x122/0x2b0
[ 2753.194121]  [<000000000010d034>] do_extint+0x16c/0x170
[ 2753.194123]  [<00000000005e206e>] ext_skip+0x38/0x3e
[ 2753.194129]  [<000000000012157c>] gmap_test_and_clear_dirty+0xcc/0x118
[ 2753.194134] ([<00000000001214ea>] gmap_test_and_clear_dirty+0x3a/0x118)
[ 2753.194137]  [<0000000000132da4>] kvm_vm_ioctl_get_dirty_log+0xd4/0x1b0
[ 2753.194143]  [<000000000012ac12>] kvm_vm_ioctl+0x21a/0x548
[ 2753.194146]  [<00000000002b57f6>] do_vfs_ioctl+0x30e/0x518
[ 2753.194149]  [<00000000002b5a9c>] SyS_ioctl+0x9c/0xb0
[ 2753.194151]  [<00000000005e1ae6>] sysc_tracego+0x14/0x1a
[ 2753.194153]  [<000003ffb75f3972>] 0x3ffb75f3972

We should do a cond_resched in here.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:57 +01:00
Christian Borntraeger ab99a1cc7a KVM: s390: do not take mmap_sem on dirty log query
Dirty log query can take a long time for huge guests.
Holding the mmap_sem for very long times  can cause some unwanted
latencies.
Turns out that we do not need to hold the mmap semaphore.
We hold the slots_lock for gfn->hva translation and walk the page
tables with that address, so no need to look at the VMAs. KVM also
holds a reference to the mm, which should prevent other things
going away. During the walk we take the necessary ptl locks.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:56 +01:00
David Hildenbrand 9b0d721a07 KVM: s390: instruction-fetching exceptions on SIE faults
On instruction-fetch exceptions, we have to forward the PSW by any
valid ilc and correctly use that ilc when injecting the irq. Injection
will already take care of rewinding the PSW if we injected a nullifying
program irq, so we don't need special handling prior to injection.

Until now, autodetection would have guessed an ilc of 0.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:54 +01:00
David Hildenbrand 5631792053 KVM: s390: provide prog irq ilc on SIE faults
On SIE faults, the ilc cannot be detected automatically, as the icptcode
is 0. The ilc indicated in the program irq will always be 0. Therefore we
have to manually specify the ilc in order to tell the guest which ilen was
used when forwarding the PSW.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:53 +01:00
David Hildenbrand eaa4f41642 KVM: s390: irq delivery should not rely on icptcode
Program irq injection during program irq intercepts is the last candidates
that injects nullifying irqs and relies on delivery to do the right thing.

As we should not rely on the icptcode during any delivery (because that
value will not be migrated), let's add a flag, telling prog IRQ delivery
to not rewind the PSW in case of nullifying prog IRQs.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:53 +01:00
David Hildenbrand f6af84e7e7 KVM: s390: clean up prog irq injection on prog irq icpts
__extract_prog_irq() is used only once for getting the program check data
in one place. Let's combine it with an injection function to avoid a memset
and to prevent misuse on injection by simplifying the interface to only
have the VCPU as parameter.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:52 +01:00
David Hildenbrand 6597732275 KVM: s390: read the correct opcode on SIE faults
Let's use our fresh new function read_guest_instr() to access
guest storage via the correct addressing schema.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:51 +01:00
David Hildenbrand 34346b9a93 KVM: s390: gaccess: implement instruction fetching mode
When an instruction is to be fetched, special handling applies to
secondary-space mode and access-register mode. The instruction is to be
fetched from primary space.

We can easily support this by selecting the right asce for translation.
Access registers will never be used during translation, so don't
include them in the interface. As we only want to read from the current
PSW address for now, let's also hide that detail.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:51 +01:00
David Hildenbrand 92c9632119 KVM: s390: gaccess: introduce access modes
We will need special handling when fetching instructions, so let's
introduce new guest access modes GACC_FETCH and GACC_STORE instead
of a write flag. An additional patch will then introduce GACC_IFETCH.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:50 +01:00
David Hildenbrand 634790b827 KVM: s390: migration / injection of prog irq ilc
We have to migrate the program irq ilc and someday we will have to
specify the ilc without KVM trying to autodetect the value.

Let's reuse one of the spare fields in our program irq that should
always be set to 0 by user space. Because we also want to make use
of 0 ilcs ("not available"), we need a validity indicator.

If no valid ilc is given, we try to autodetect the ilc via the current
icptcode and icptstatus + parameter and store the valid ilc in the
irq structure.

This has a nice effect: QEMU's making use of KVM_S390_IRQ /
KVM_S390_SET_IRQ_STATE / KVM_S390_GET_IRQ_STATE for migration will
directly migrate the ilc without any changes.

Please note that we use bit 0 as validity and bit 1,2 for the ilc, so
by applying the ilc mask we directly get the ilen which is usually what
we work with.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:50 +01:00
David Hildenbrand 0e8bc06a2f KVM: s390: PSW forwarding / rewinding / ilc rework
We have some confusion about ilc vs. ilen in our current code. So let's
correctly use the term ilen when dealing with (ilc << 1).

Program irq injection didn't take care of the correct ilc in case of
irqs triggered by EXECUTE functions, let's provide one function
kvm_s390_get_ilen() to take care of all that.

Also, manually specifying in intercept handlers the size of the
instruction (and sometimes overwriting that value for EXECUTE internally)
doesn't make too much sense. So also provide the functions:
- kvm_s390_retry_instr to retry the currently intercepted instruction
- kvm_s390_rewind_psw to rewind the PSW without internal overwrites
- kvm_s390_forward_psw to forward the PSW

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:49 +01:00
David Hildenbrand 6fd8e67dd8 KVM: s390: sync of fp registers via kvm_run
As we already store the floating point registers in the vector save area
in floating point register format when we don't have MACHINE_HAS_VX, we can
directly expose them to user space using a new sync flag.

The floating point registers will be valid when KVM_SYNC_FPRS is set. The
fpc will also be valid when KVM_SYNC_FPRS is set.

Either KVM_SYNC_FPRS or KVM_SYNC_VRS will be enabled, never both.

Let's also change two positions where we access vrs, making the code easier
to read and one comment superfluous.

Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:49 +01:00
David Hildenbrand f6aa6dc449 KVM: s390: allow sync of fp registers via vregs
If we have MACHINE_HAS_VX, the floating point registers are stored
in the vector register format, event if the guest isn't enabled for vector
registers. So we can allow KVM_SYNC_VRS as soon as MACHINE_HAS_VX is
available.

This can in return be used by user space to support floating point
registers via struct kvm_run when the machine has vector registers.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-02-10 13:12:48 +01:00
Linus Torvalds 6b292a8abd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "An optimization for irq-restore, the SSM instruction is quite a bit
  slower than an if-statement and a STOSM.

  The copy_file_range system all is added.

  Cleanup for PCI and CIO.

  And a couple of bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/cio: update measurement characteristics
  s390/cio: ensure consistent measurement state
  s390/cio: fix measurement characteristics memleak
  s390/zcrypt: Fix cryptographic device id in kernel messages
  s390/pci: remove iomap sanity checks
  s390/pci: set error state for unusable functions
  s390/pci: fix bar check
  s390/pci: resize iomap
  s390/pci: improve ZPCI_* macros
  s390/pci: provide ZPCI_ADDR macro
  s390/pci: adjust IOMAP_MAX_ENTRIES
  s390/numa: move numa_init_late() from device to arch_initcall
  s390: remove all usages of PSW_ADDR_INSN
  s390: remove all usages of PSW_ADDR_AMODE
  s390: wire up copy_file_range syscall
  s390: remove superfluous memblock_alloc() return value checks
  s390/numa: allocate memory with correct alignment
  s390/irqflags: optimize irq restore
  s390/mm: use TASK_MAX_SIZE where applicable
2016-01-29 16:05:18 -08:00
David Hildenbrand 9abc2a08a7 KVM: s390: fix memory overwrites when vx is disabled
The kernel now always uses vector registers when available, however KVM
has special logic if support is really enabled for a guest. If support
is disabled, guest_fpregs.fregs will only contain memory for the fpu.
The kernel, however, will store vector registers into that area,
resulting in crazy memory overwrites.

Simply extending that area is not enough, because the format of the
registers also changes. We would have to do additional conversions, making
the code even more complex. Therefore let's directly use one place for
the vector/fpu registers + fpc (in kvm_run). We just have to convert the
data properly when accessing it. This makes current code much easier.

Please note that vector/fpu registers are now always stored to
vcpu->run->s.regs.vrs. Although this data is visible to QEMU and
used for migration, we only guarantee valid values to user space  when
KVM_SYNC_VRS is set. As that is only the case when we have vector
register support, we are on the safe side.

Fixes: b5510d9b68 ("s390/fpu: always enable the vector facility if it is available")
Cc: stable@vger.kernel.org # v4.4 d9a3a09af5 s390/kvm: remove dependency on struct save_area definition
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[adopt to d9a3a09af5]
2016-01-26 15:40:21 +01:00
Dong Jia Shi 14b0b4ac37 KVM: s390: Enable the KVM-VFIO device
The KVM-VFIO device is used by the QEMU VFIO device. It is used to
record the list of in-use VFIO groups so that KVM can manipulate
them.
While we don't need this on s390 currently, let's try to be like
everyone else.

Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-01-26 15:40:17 +01:00
David Hildenbrand 9c7ebb613b KVM: s390: fix guest fprs memory leak
fprs is never freed, therefore resulting in a memory leak if
kvm_vcpu_init() fails or the vcpu is destroyed.

Fixes: 9977e886cb ("s390/kernel: lazy restore fpu registers")
Cc: stable@vger.kernel.org # v4.3+
Reported-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-01-26 15:40:09 +01:00
Heiko Carstens 9cb1ccecb6 s390: remove all usages of PSW_ADDR_INSN
Yet another leftover from the 31 bit era. The usual operation
"y = x & PSW_ADDR_INSN" with the PSW_ADDR_INSN mask is a nop for
CONFIG_64BIT.

Therefore remove all usages and hope the code is a bit less confusing.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2016-01-19 12:14:03 +01:00
Linus Torvalds cbd88cd4c0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
 "Among the traditional bug fixes and cleanups are some improvements:

   - A tool to generated the facility lists, generating the bit fields
     by hand has been a source of bugs in the past

   - The spinlock loop is reordered to avoid bursts of hypervisor calls

   - Add support for the open-for-business interface to the service
     element

   - The get_cpu call is added to the vdso

   - A set of tracepoints is defined for the common I/O layer

   - The deprecated sclp_cpi module is removed

   - Update default configuration"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (56 commits)
  s390/sclp: fix possible control register corruption
  s390: fix normalization bug in exception table sorting
  s390/configs: update default configurations
  s390/vdso: optimize getcpu system call
  s390: drop smp_mb in vdso_init
  s390: rename struct _lowcore to struct lowcore
  s390/mem_detect: use unsigned longs
  s390/ptrace: get rid of long longs in psw_bits
  s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields
  s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK
  s390/Kconfig: remove pointless 64 bit dependencies
  s390/dasd: fix failfast for disconnected devices
  s390/con3270: testing return kzalloc retval
  s390/hmcdrv: constify hmcdrv_ftp_ops structs
  s390/cio: add NULL test
  s390/cio: Change I/O instructions from inline to normal functions
  s390/cio: Introduce common I/O layer tracepoints
  s390/cio: Consolidate inline assemblies and related data definitions
  s390/cio: Fix incorrect xsch opcode specification
  s390/cio: Remove unused inline assemblies
  ...
2016-01-13 13:16:16 -08:00
Heiko Carstens c667aeacc1 s390: rename struct _lowcore to struct lowcore
Finally get rid of the leading underscore. I tried this already two or
three years ago, however Michael Holzheu objected since this would
break the crash utility (again).

However Michael integrated support for the new name into the crash
utility back then, so it doesn't break if the name will be changed
now.  So finally get rid of the ever confusing leading underscore.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-01-11 12:27:15 +01:00
Fan Zhang c6e5f16637 KVM: s390: implement the RI support of guest
This patch adds runtime instrumentation support for KVM guest. We need to
setup a save area for the runtime instrumentation-controls control block(RICCB)
and implement the necessary interfaces to live migrate the guest settings.

We setup the sie control block in a way, that the runtime
instrumentation instructions of a guest are handled by hardware.

We also add a capability KVM_CAP_S390_RI to make this feature opt-in as
it needs migration support.

Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-01-07 14:48:26 +01:00
Michael S. Tsirkin c57ee5faf4 kvm/s390: drop unpaired smp_mb
smp_mb on vcpu destroy isn't paired with anything, violating pairing
rules, and seems to be useless.

Drop it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <1452010811-25486-1-git-send-email-mst@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-01-07 14:48:26 +01:00
Guenther Hutzl 32e6b236d2 KVM: s390: consider system MHA for guest storage
Verify that the guest maximum storage address is below the MHA (maximum
host address) value allowed on the host.

Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com>
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
[adopt to match recent limit,size changes]

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-12-15 17:08:22 +01:00
Dominik Dingel a3a92c31bf KVM: s390: fix mismatch between user and in-kernel guest limit
While the userspace interface requests the maximum size the gmap code
expects to get a maximum address.

This error resulted in bigger page tables than necessary for some guest
sizes, e.g. a 2GB guest used 3 levels instead of 2.

At the same time we introduce KVM_S390_NO_MEM_LIMIT, which allows in a
bright future that a guest spans the complete 64 bit address space.

We also switch to TASK_MAX_SIZE for the initial memory size, this is a
cosmetic change as the previous size also resulted in a 4 level pagetable
creation.

Reported-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-12-15 17:08:21 +01:00
Christian Borntraeger 8335713ad0 KVM: s390: obey kptr_restrict in traces
The s390dbf and trace events provide a debugfs interface.
If kptr_restrict is active, we should not expose kernel
pointers. We can fence the debugfs output by using %pK
instead of %p.

Cc: Kees Cook <keescook@chromium.org>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-12-15 17:06:32 +01:00
Christian Borntraeger 7ec7c8c70b KVM: s390: use assignment instead of memcpy
Replace two memcpy with proper assignment.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-12-15 16:06:48 +01:00
Christian Borntraeger 2f8a43d45d KVM: s390: remove redudant assigment of error code
rc already contains -ENOMEM, no need to assign it twice.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2015-11-30 12:47:13 +01:00
Heiko Carstens a6aacc3f87 KVM: s390: remove pointless test_facility(2) check
This evaluates always to 'true'.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:12 +01:00
David Hildenbrand 07197fd05f KVM: s390: don't load kvm without virtualization support
If we don't have support for virtualization (SIE), e.g. when running under
a hypervisor not supporting execution of the SIE instruction, we should
immediately abort loading the kvm module, as the SIE instruction cannot
be enabled dynamically.

Currently, the SIE instructions fails with an exception on a non-SIE
host, resulting in the guest making no progress, instead of failing hard.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:12 +01:00
David Hildenbrand 4215825eeb KVM: s390: don't switch to ESCA for ucontrol
sca_add_vpcu is not called for ucontrol guests. We must also not
apply the sca checking for sca_can_add_vcpu as ucontrol guests
do not have to follow the sca limits.

As common code already checks that id < KVM_MAX_VCPUS all other
data structures are safe as well.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:11 +01:00
David Hildenbrand eaa78f3432 KVM: s390: cleanup sca_add_vcpu
Now that we already have kvm and the VCPU id set for the VCPU, we can
convert sda_add_vcpu to look much more like sda_del_vcpu.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:10 +01:00
David Hildenbrand 10ce32d5b0 KVM: s390: always set/clear the SCA sda field
Let's always set and clear the sda when enabling/disabling a VCPU.
Dealing with sda being set to something else makes no sense anymore
as we enable a VCPU in the SCA now after it has been registered at
the VM.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:10 +01:00
David Hildenbrand 2550882449 KVM: s390: fix SCA related races and double use
If something goes wrong in kvm_arch_vcpu_create, the VCPU has already
been added to the sca but will never be removed. Trying to create VCPUs
with duplicate ids (e.g. after a failed attempt) is problematic.

Also, when creating multiple VCPUs in parallel, we could theoretically
forget to set the correct SCA when the switch to ESCA happens just
before the VCPU is registered.

Let's add the VCPU to the SCA in kvm_arch_vcpu_postcreate, where we can
be sure that no duplicate VCPU with the same id is around and the VCPU
has already been registered at the VM. We also have to make sure to update
ECB at that point.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:09 +01:00
David Hildenbrand 5f3fe620a5 KVM: s390: we always have a SCA
Having no sca can never happen, even when something goes wrong when
switching to ESCA. Otherwise we would have a serious bug.
Let's remove this superfluous check.

Acked-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:09 +01:00
David Hildenbrand 2c1bb2be98 KVM: s390: fast path for sca_ext_call_pending
If CPUSTAT_ECALL_PEND isn't set, we can't have an external call pending,
so we can directly avoid taking the lock.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:09 +01:00
Eugene (jno) Dvurechenski fe0edcb731 KVM: s390: Enable up to 248 VCPUs per VM
This patch allows s390 to have more than 64 VCPUs for a guest (up to
248 for memory usage considerations), if supported by the underlaying
hardware (sclp.has_esca).

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:08 +01:00
Eugene (jno) Dvurechenski 5e04431523 KVM: s390: Introduce switching code
This patch adds code that performs transparent switch to Extended
SCA on addition of 65th VCPU in a VM. Disposal of ESCA is added too.
The entier ESCA functionality, however, is still not enabled.
The enablement will be provided in a separate patch.

This patch also uses read/write lock protection of SCA and its subfields for
possible disposal at the BSCA-to-ESCA transition. While only Basic SCA needs such
a protection (for the swap), any SCA access is now guarded.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:08 +01:00
Eugene (jno) Dvurechenski 7d43bafcff KVM: s390: Make provisions for ESCA utilization
This patch updates the routines (sca_*) to provide transparent access
to and manipulation on the data for both Basic and Extended SCA in use.
The kvm.arch.sca is generalized to (void *) to handle BSCA/ESCA cases.
Also the kvm.arch.use_esca flag is provided.
The actual functionality is kept the same.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:08 +01:00
Eugene (jno) Dvurechenski bc784ccee5 KVM: s390: Introduce new structures
This patch adds new structures and updates some existing ones to
provide the base for Extended SCA functionality.

The old sca_* structures were renamed to bsca_* to keep things uniform.

The access to fields of SIGP controls were turned into bitfields instead
of hardcoded bitmasks.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:07 +01:00
Eugene (jno) Dvurechenski a6e2f683e7 KVM: s390: Provide SCA-aware helpers for VCPU add/del
This patch provides SCA-aware helpers to create/delete a VCPU.
This is to prepare for upcoming introduction of Extended SCA support.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:07 +01:00
Eugene (jno) Dvurechenski a5bd764734 KVM: s390: Generalize access to SIGP controls
This patch generalizes access to the SIGP controls, which is a part of SCA.
This is to prepare for upcoming introduction of Extended SCA support.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:06 +01:00
Eugene (jno) Dvurechenski 605145103a KVM: s390: Generalize access to IPTE controls
This patch generalizes access to the IPTE controls, which is a part of SCA.
This is to prepare for upcoming introduction of Extended SCA support.

Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:06 +01:00
David Hildenbrand 71f116bfed KVM: s390: rewrite vcpu_post_run and drop out early
Let's rewrite this function to better reflect how we actually handle
exit_code. By dropping out early we can save a few cycles. This
especially speeds up sie exits caused by host irqs.

Also, let's move the special -EOPNOTSUPP for intercepts to
the place where it belongs and convert it to -EREMOTE.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-30 12:47:05 +01:00
David Hildenbrand e09fefdeeb KVM: Use common function for VCPU lookup by id
Let's reuse the new common function for VPCU lookup by id.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[split out the new function into a separate patch]
2015-11-30 12:47:04 +01:00
Martin Schwidefsky d9a3a09af5 s390/kvm: remove dependency on struct save_area definition
Replace the offsets based on the struct area_area with the offset
constants from asm-offsets.c based on the struct _lowcore.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-11-27 09:24:13 +01:00
David Hildenbrand 152e9f65d6 KVM: s390: fix wrong lookup of VCPUs by array index
For now, VCPUs were always created sequentially with incrementing
VCPU ids. Therefore, the index in the VCPUs array matched the id.

As sequential creation might change with cpu hotplug, let's use
the correct lookup function to find a VCPU by id, not array index.

Let's also use kvm_lookup_vcpu() for validation of the sending VCPU
on external call injection.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # db27a7a KVM: Provide function for VCPU lookup by id
2015-11-19 14:47:43 +01:00
David Hildenbrand b85de33a1a KVM: s390: avoid memory overwrites on emergency signal injection
Commit 383d0b0501 ("KVM: s390: handle pending local interrupts via
bitmap") introduced a possible memory overwrite from user space.

User space could pass an invalid emergency signal code (sending VCPU)
and therefore exceed the bitmap. Let's take care of this case and
check that the id is in the valid range.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org # v3.19+ db27a7a KVM: Provide function for VCPU lookup by id
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-19 14:47:32 +01:00
Heiko Carstens 03c02807e2 KVM: s390: fix pfmf intercept handler
The pfmf intercept handler should check if the EDAT 1 facility
is installed in the guest, not if it is installed in the host.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-11-19 11:08:17 +01:00
David Hildenbrand 5967c17b11 KVM: s390: enable SIMD only when no VCPUs were created
We should never allow to enable/disable any facilities for the guest
when other VCPUs were already created.

kvm_arch_vcpu_(load|put) relies on SIMD not changing during runtime.
If somebody would create and run VCPUs and then decides to enable
SIMD, undefined behaviour could be possible (e.g. vector save area
not being set up).

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # 4.1+
2015-11-19 11:08:16 +01:00
Linus Torvalds 933425fb00 s390: A bunch of fixes and optimizations for interrupt and time
handling.
 
 PPC: Mostly bug fixes.
 
 ARM: No big features, but many small fixes and prerequisites including:
 - a number of fixes for the arch-timer
 - introducing proper level-triggered semantics for the arch-timers
 - a series of patches to synchronously halt a guest (prerequisite for
   IRQ forwarding)
 - some tracepoint improvements
 - a tweak for the EL2 panic handlers
 - some more VGIC cleanups getting rid of redundant state
 
 x86: quite a few changes:
 
 - support for VT-d posted interrupts (i.e. PCI devices can inject
 interrupts directly into vCPUs).  This introduces a new component (in
 virt/lib/) that connects VFIO and KVM together.  The same infrastructure
 will be used for ARM interrupt forwarding as well.
 
 - more Hyper-V features, though the main one Hyper-V synthetic interrupt
 controller will have to wait for 4.5.  These will let KVM expose Hyper-V
 devices.
 
 - nested virtualization now supports VPID (same as PCID but for vCPUs)
 which makes it quite a bit faster
 
 - for future hardware that supports NVDIMM, there is support for clflushopt,
 clwb, pcommit
 
 - support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in
 userspace, which reduces the attack surface of the hypervisor
 
 - obligatory smattering of SMM fixes
 
 - on the guest side, stable scheduler clock support was rewritten to not
 require help from the hypervisor.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "First batch of KVM changes for 4.4.

  s390:
     A bunch of fixes and optimizations for interrupt and time handling.

  PPC:
     Mostly bug fixes.

  ARM:
     No big features, but many small fixes and prerequisites including:

      - a number of fixes for the arch-timer

      - introducing proper level-triggered semantics for the arch-timers

      - a series of patches to synchronously halt a guest (prerequisite
        for IRQ forwarding)

      - some tracepoint improvements

      - a tweak for the EL2 panic handlers

      - some more VGIC cleanups getting rid of redundant state

  x86:
     Quite a few changes:

      - support for VT-d posted interrupts (i.e. PCI devices can inject
        interrupts directly into vCPUs).  This introduces a new
        component (in virt/lib/) that connects VFIO and KVM together.
        The same infrastructure will be used for ARM interrupt
        forwarding as well.

      - more Hyper-V features, though the main one Hyper-V synthetic
        interrupt controller will have to wait for 4.5.  These will let
        KVM expose Hyper-V devices.

      - nested virtualization now supports VPID (same as PCID but for
        vCPUs) which makes it quite a bit faster

      - for future hardware that supports NVDIMM, there is support for
        clflushopt, clwb, pcommit

      - support for "split irqchip", i.e.  LAPIC in kernel +
        IOAPIC/PIC/PIT in userspace, which reduces the attack surface of
        the hypervisor

      - obligatory smattering of SMM fixes

      - on the guest side, stable scheduler clock support was rewritten
        to not require help from the hypervisor"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits)
  KVM: VMX: Fix commit which broke PML
  KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0()
  KVM: x86: allow RSM from 64-bit mode
  KVM: VMX: fix SMEP and SMAP without EPT
  KVM: x86: move kvm_set_irq_inatomic to legacy device assignment
  KVM: device assignment: remove pointless #ifdefs
  KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic
  KVM: x86: zero apic_arb_prio on reset
  drivers/hv: share Hyper-V SynIC constants with userspace
  KVM: x86: handle SMBASE as physical address in RSM
  KVM: x86: add read_phys to x86_emulate_ops
  KVM: x86: removing unused variable
  KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs
  KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()
  KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings
  KVM: arm/arm64: Optimize away redundant LR tracking
  KVM: s390: use simple switch statement as multiplexer
  KVM: s390: drop useless newline in debugging data
  KVM: s390: SCA must not cross page boundaries
  KVM: arm: Do not indent the arguments of DECLARE_BITMAP
  ...
2015-11-05 16:26:26 -08:00
Christian Borntraeger 46b708ea87 KVM: s390: use simple switch statement as multiplexer
We currently do some magic shifting (by exploiting that exit codes
are always a multiple of 4) and a table lookup to jump into the
exit handlers. This causes some calculations and checks, just to
do an potentially expensive function call.

Changing that to a switch statement gives the compiler the chance
to inline and dynamically decide between jump tables or inline
compare and branches. In addition it makes the code more readable.

bloat-o-meter gives me a small reduction in code size:

add/remove: 0/7 grow/shrink: 1/1 up/down: 986/-1334 (-348)
function                                     old     new   delta
kvm_handle_sie_intercept                      72    1058    +986
handle_prog                                  704     696      -8
handle_noop                                   54       -     -54
handle_partial_execution                      60       -     -60
intercept_funcs                              120       -    -120
handle_instruction                           198       -    -198
handle_validity                              210       -    -210
handle_stop                                  316       -    -316
handle_external_interrupt                    368       -    -368

Right now my gcc does conditional branches instead of jump tables.
The inlining seems to give us enough cycles as some micro-benchmarking
shows minimal improvements, but still in noise.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-10-29 15:59:11 +01:00
Christian Borntraeger 58c383c62e KVM: s390: drop useless newline in debugging data
the s390 debug feature does not need newlines. In fact it will
result in empty lines. Get rid of 4 leftovers.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-10-29 15:58:54 +01:00
David Hildenbrand c5c2c39346 KVM: s390: SCA must not cross page boundaries
We seemed to have missed a few corner cases in commit f6c137ff00
("KVM: s390: randomize sca address").

The SCA has a maximum size of 2112 bytes. By setting the sca_offset to
some unlucky numbers, we exceed the page.

0x7c0 (1984) -> Fits exactly
0x7d0 (2000) -> 16 bytes out
0x7e0 (2016) -> 32 bytes out
0x7f0 (2032) -> 48 bytes out

One VCPU entry is 32 bytes long.

For the last two cases, we actually write data to the other page.
1. The address of the VCPU.
2. Injection/delivery/clearing of SIGP externall calls via SIGP IF.

Especially the 2. happens regularly. So this could produce two problems:
1. The guest losing/getting external calls.
2. Random memory overwrites in the host.

So this problem happens on every 127 + 128 created VM with 64 VCPUs.

Cc: stable@vger.kernel.org # v3.15+
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-29 15:58:41 +01:00
Hendrik Brueckner b5510d9b68 s390/fpu: always enable the vector facility if it is available
If the kernel detects that the s390 hardware supports the vector
facility, it is enabled by default at an early stage.  To force
it off, use the novx kernel parameter.  Note that there is a small
time window, where the vector facility is enabled before it is
forced to be off.

With enabling the vector facility by default, the FPU save and
restore functions can be improved.  They do not longer require
to manage expensive control register updates to enable or disable
the vector enablement control for particular processes.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-10-14 14:32:08 +02:00
David Hildenbrand 60417fcc2b KVM: s390: factor out reading of the guest TOD clock
Let's factor this out and always use get_tod_clock_fast() when
reading the guest TOD.

STORE CLOCK FAST does not do serialization and, therefore, might
result in some fuzziness between different processors in a way
that subsequent calls on different CPUs might have time stamps that
are earlier. This semantics is fine though for all KVM use cases.
To make it obvious that the new function has STORE CLOCK FAST
semantics we name it kvm_s390_get_tod_clock_fast.

With this patch, we only have a handful of places were we
have to care about STP sync (using preempt_disable() logic).

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-10-13 15:50:35 +02:00