Commit Graph

533963 Commits

Author SHA1 Message Date
Thomas Huth f35f3a48d6 KVM: PPC: Book3S: Fix size of the PSPB register
The size of the Problem State Priority Boost Register is only
32 bits, but the kvm_vcpu_arch->pspb variable is declared as
"ulong", ie. 64-bit. However, the assembler code accesses this
variable with 32-bit accesses, and the KVM_REG_PPC_PSPB macro
is defined with SIZE_U32, too, so that the current code is
broken on big endian hosts: kvmppc_get_one_reg_hv() will only
return zero for this register since it is using the wrong half
of the pspb variable. Let's fix this problem by adjusting the
size of the pspb field in the kvm_vcpu_arch structure.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-03 16:09:09 +10:00
Gautham R. Shenoy 06554d9f6c KVM: PPC: Book3S HV: Exit on H_DOORBELL if HOST_IPI is set
The code that handles the case when we receive a H_DOORBELL interrupt
has a comment which says "Hypervisor doorbell - exit only if host IPI
flag set".  However, the current code does not actually check if the
host IPI flag is set.  This is due to a comparison instruction that
got missed.

As a result, the current code performs the exit to host only
if some sibling thread or a sibling sub-core is exiting to the
host.  This implies that, an IPI sent to a sibling core in
(subcores-per-core != 1) mode will be missed by the host unless the
sibling core is on the exit path to the host.

This patch adds the missing comparison operation which will ensure
that when HOST_IPI flag is set, we unconditionally exit to the host.

Fixes: 66feed61cd
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-03 16:08:34 +10:00
Gautham R. Shenoy 7f23532866 KVM: PPC: Book3S HV: Fix race in starting secondary threads
The current dynamic micro-threading code has a race due to which a
secondary thread naps when it is supposed to be running a vcpu. As a
side effect of this, on a guest exit, the primary thread in
kvmppc_wait_for_nap() finds that this secondary thread hasn't cleared
its vcore pointer. This results in "CPU X seems to be stuck!"
warnings.

The race is possible since the primary thread on exiting the guests
only waits for all the secondaries to clear its vcore pointer. It
subsequently expects the secondary threads to enter nap while it
unsplits the core. A secondary thread which hasn't yet entered the nap
will loop in kvm_no_guest until its vcore pointer and the do_nap flag
are unset. Once the core has been unsplit, a new vcpu thread can grab
the core and set the do_nap flag *before* setting the vcore pointers
of the secondary. As a result, the secondary thread will now enter nap
via kvm_unsplit_nap instead of running the guest vcpu.

Fix this by setting the do_nap flag after setting the vcore pointer in
the PACA of the secondary in kvmppc_run_core. Also, ensure that a
secondary thread doesn't nap in kvm_unsplit_nap when the vcore pointer
in its PACA struct is set.

Fixes: b4deba5c41
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-03 16:07:42 +10:00
Paolo Bonzini e3dbc572fe Patch queue for ppc - 2015-08-22
Highlights for KVM PPC this time around:
 
   - Book3S: A few bug fixes
   - Book3S: Allow micro-threading on POWER8
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Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm-queue

Patch queue for ppc - 2015-08-22

Highlights for KVM PPC this time around:

  - Book3S: A few bug fixes
  - Book3S: Allow micro-threading on POWER8
2015-08-22 14:57:59 -07:00
Paolo Bonzini ce8c669e44 KVM/ARM changes for 4.3
- Full debug support for arm64
 - Active state switching for timer interrupts
 - Lazy FP/SIMD save/restore for arm64
 - Generic ARMv8 target
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Merge tag 'kvm-arm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-queue

KVM/ARM changes for 4.3

- Full debug support for arm64
- Active state switching for timer interrupts
- Lazy FP/SIMD save/restore for arm64
- Generic ARMv8 target
2015-08-22 14:53:22 -07:00
Sam bobroff c63517c2e3 KVM: PPC: Book3S: correct width in XER handling
In 64 bit kernels, the Fixed Point Exception Register (XER) is a 64
bit field (e.g. in kvm_regs and kvm_vcpu_arch) and in most places it is
accessed as such.

This patch corrects places where it is accessed as a 32 bit field by a
64 bit kernel.  In some cases this is via a 32 bit load or store
instruction which, depending on endianness, will cause either the
lower or upper 32 bits to be missed.  In another case it is cast as a
u32, causing the upper 32 bits to be cleared.

This patch corrects those places by extending the access methods to
64 bits.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:19 +02:00
Paul Mackerras 563a1e93af KVM: PPC: Book3S HV: Fix preempted vcore stolen time calculation
Whenever a vcore state is VCORE_PREEMPT we need to be counting stolen
time for it.  This currently isn't the case when we have a vcore that
no longer has any runnable threads in it but still has a runner task,
so we do an explicit call to kvmppc_core_start_stolen() in that case.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:19 +02:00
Paul Mackerras 402813fe39 KVM: PPC: Book3S HV: Fix preempted vcore list locking
When a vcore gets preempted, we put it on the preempted vcore list for
the current CPU.  The runner task then calls schedule() and comes back
some time later and takes itself off the list.  We need to be careful
to lock the list that it was put onto, which may not be the list for the
current CPU since the runner task may have moved to another CPU.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:19 +02:00
Paul Mackerras cdeee51842 KVM: PPC: Book3S HV: Implement H_CLEAR_REF and H_CLEAR_MOD
This adds implementations for the H_CLEAR_REF (test and clear reference
bit) and H_CLEAR_MOD (test and clear changed bit) hypercalls.

When clearing the reference or change bit in the guest view of the HPTE,
we also have to clear it in the real HPTE so that we can detect future
references or changes.  When we do so, we transfer the R or C bit value
to the rmap entry for the underlying host page so that kvm_age_hva_hv(),
kvm_test_age_hva_hv() and kvmppc_hv_get_dirty_log() know that the page
has been referenced and/or changed.

These hypercalls are not used by Linux guests.  These implementations
have been tested using a FreeBSD guest.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:18 +02:00
Paul Mackerras 08fe1e7bd2 KVM: PPC: Book3S HV: Fix bug in dirty page tracking
This fixes a bug in the tracking of pages that get modified by the
guest.  If the guest creates a large-page HPTE, writes to memory
somewhere within the large page, and then removes the HPTE, we only
record the modified state for the first normal page within the large
page, when in fact the guest might have modified some other normal
page within the large page.

To fix this we use some unused bits in the rmap entry to record the
order (log base 2) of the size of the page that was modified, when
removing an HPTE.  Then in kvm_test_clear_dirty_npages() we use that
order to return the correct number of modified pages.

The same thing could in principle happen when removing a HPTE at the
host's request, i.e. when paging out a page, except that we never
page out large pages, and the guest can only create large-page HPTEs
if the guest RAM is backed by large pages.  However, we also fix
this case for the sake of future-proofing.

The reference bit is also subject to the same loss of information.  We
don't make the same fix here for the reference bit because there isn't
an interface for userspace to find out which pages the guest has
referenced, whereas there is one for userspace to find out which pages
the guest has modified.  Because of this loss of information, the
kvm_age_hva_hv() and kvm_test_age_hva_hv() functions might incorrectly
say that a page has not been referenced when it has, but that doesn't
matter greatly because we never page or swap out large pages.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:18 +02:00
Paul Mackerras 1e5bf454f5 KVM: PPC: Book3S HV: Fix race in reading change bit when removing HPTE
The reference (R) and change (C) bits in a HPT entry can be set by
hardware at any time up until the HPTE is invalidated and the TLB
invalidation sequence has completed.  This means that when removing
a HPTE, we need to read the HPTE after the invalidation sequence has
completed in order to obtain reliable values of R and C.  The code
in kvmppc_do_h_remove() used to do this.  However, commit 6f22bd3265
("KVM: PPC: Book3S HV: Make HTAB code LE host aware") removed the
read after invalidation as a side effect of other changes.  This
restores the read of the HPTE after invalidation.

The user-visible effect of this bug would be that when migrating a
guest, there is a small probability that a page modified by the guest
and then unmapped by the guest might not get re-transmitted and thus
the destination might end up with a stale copy of the page.

Fixes: 6f22bd3265
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:18 +02:00
Paul Mackerras b4deba5c41 KVM: PPC: Book3S HV: Implement dynamic micro-threading on POWER8
This builds on the ability to run more than one vcore on a physical
core by using the micro-threading (split-core) modes of the POWER8
chip.  Previously, only vcores from the same VM could be run together,
and (on POWER8) only if they had just one thread per core.  With the
ability to split the core on guest entry and unsplit it on guest exit,
we can run up to 8 vcpu threads from up to 4 different VMs, and we can
run multiple vcores with 2 or 4 vcpus per vcore.

Dynamic micro-threading is only available if the static configuration
of the cores is whole-core mode (unsplit), and only on POWER8.

To manage this, we introduce a new kvm_split_mode struct which is
shared across all of the subcores in the core, with a pointer in the
paca on each thread.  In addition we extend the core_info struct to
have information on each subcore.  When deciding whether to add a
vcore to the set already on the core, we now have two possibilities:
(a) piggyback the vcore onto an existing subcore, or (b) start a new
subcore.

Currently, when any vcpu needs to exit the guest and switch to host
virtual mode, we interrupt all the threads in all subcores and switch
the core back to whole-core mode.  It may be possible in future to
allow some of the subcores to keep executing in the guest while
subcore 0 switches to the host, but that is not implemented in this
patch.

This adds a module parameter called dynamic_mt_modes which controls
which micro-threading (split-core) modes the code will consider, as a
bitmap.  In other words, if it is 0, no micro-threading mode is
considered; if it is 2, only 2-way micro-threading is considered; if
it is 4, only 4-way, and if it is 6, both 2-way and 4-way
micro-threading mode will be considered.  The default is 6.

With this, we now have secondary threads which are the primary thread
for their subcore and therefore need to do the MMU switch.  These
threads will need to be started even if they have no vcpu to run, so
we use the vcore pointer in the PACA rather than the vcpu pointer to
trigger them.

It is now possible for thread 0 to find that an exit has been
requested before it gets to switch the subcore state to the guest.  In
that case we haven't added the guest's timebase offset to the
timebase, so we need to be careful not to subtract the offset in the
guest exit path.  In fact we just skip the whole path that switches
back to host context, since we haven't switched to the guest context.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:17 +02:00
Paul Mackerras ec25716508 KVM: PPC: Book3S HV: Make use of unused threads when running guests
When running a virtual core of a guest that is configured with fewer
threads per core than the physical cores have, the extra physical
threads are currently unused.  This makes it possible to use them to
run one or more other virtual cores from the same guest when certain
conditions are met.  This applies on POWER7, and on POWER8 to guests
with one thread per virtual core.  (It doesn't apply to POWER8 guests
with multiple threads per vcore because they require a 1-1 virtual to
physical thread mapping in order to be able to use msgsndp and the
TIR.)

The idea is that we maintain a list of preempted vcores for each
physical cpu (i.e. each core, since the host runs single-threaded).
Then, when a vcore is about to run, it checks to see if there are
any vcores on the list for its physical cpu that could be
piggybacked onto this vcore's execution.  If so, those additional
vcores are put into state VCORE_PIGGYBACK and their runnable VCPU
threads are started as well as the original vcore, which is called
the master vcore.

After the vcores have exited the guest, the extra ones are put back
onto the preempted list if any of their VCPUs are still runnable and
not idle.

This means that vcpu->arch.ptid is no longer necessarily the same as
the physical thread that the vcpu runs on.  In order to make it easier
for code that wants to send an IPI to know which CPU to target, we
now store that in a new field in struct vcpu_arch, called thread_cpu.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:17 +02:00
Tudor Laurentiu 845ac985cf KVM: PPC: add missing pt_regs initialization
On this switch branch the regs initialization
doesn't happen so add it.
This was found with the help of a static
code analysis tool.

Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:17 +02:00
Thomas Huth 5358a96341 KVM: PPC: Fix warnings from sparse
When compiling the KVM code for POWER with "make C=1", sparse
complains about functions missing proper prototypes and a 64-bit
constant missing the ULL prefix. Let's fix this by making the
functions static or by including the proper header with the
prototypes, and by appending a ULL prefix to the constant
PPC_MPPE_ADDRESS_MASK.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:16 +02:00
Thomas Huth 129fd4233b KVM: PPC: Remove PPC970 from KVM_BOOK3S_64_HV text in Kconfig
Since the PPC970 support has been removed from the kvm-hv kernel
module recently, we should also reflect this change in the help
text of the corresponding Kconfig option.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:16 +02:00
Tudor Laurentiu f5ffe330f5 KVM: PPC: fix suspicious use of conditional operator
This was signaled by a static code analysis tool.

Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Reviewed-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22 11:16:16 +02:00
Mario Smarduch 054167b3d5 arm: KVM: keep arm vfp/simd exit handling consistent with arm64
After enhancing arm64 FP/SIMD exit handling, ARMv7 VFP exit branch is moved
to guest trap handling. This allows us to keep exit handling flow between both
architectures consistent.

Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-19 22:27:58 +01:00
Mario Smarduch 33c76a0b81 arm64: KVM: Optimize arm64 skip 30-50% vfp/simd save/restore on exits
This patch only saves and restores FP/SIMD registers on Guest access. To do
this cptr_el2 FP/SIMD trap is set on Guest entry and later checked on exit.
lmbench, hackbench show significant improvements, for 30-50% exits FP/SIMD
context is not saved/restored

[chazy/maz: fixed save/restore logic for 32bit guests]

Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-19 22:25:19 +01:00
Andy Lutomirski 4d283ec908 x86/kvm: Rename VMX's segment access rights defines
VMX encodes access rights differently from LAR, and the latter is
most likely what x86 people think of when they think of "access
rights".

Rename them to avoid confusion.

Cc: kvm@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-15 00:47:13 +02:00
Paolo Bonzini ae6c0aa6ae KVM: s390: fix and feature for kvm/next (4.3)
1. error handling for irq routes
 2. Gracefully handle STP time changes
    s390 supports a protocol for syncing different systems via the stp
    protocol that will steer the TOD clocks to keep all participating
    clocks below the round trip time between the system. In case of
    specific out of sync event Linux can opt-in to accept sync checks.
    This will result in non-monotonic jumps of the TOD clock, which
    Linux will correct via time offsets to keep the wall clock time
    monotonic. Now: KVM guests also base their time on the host TOD,
    so we need to fixup the offset for them as well.
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Merge tag 'kvm-s390-next-20150812' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: fix and feature for kvm/next (4.3)

1. error handling for irq routes
2. Gracefully handle STP time changes
   s390 supports a protocol for syncing different systems via the stp
   protocol that will steer the TOD clocks to keep all participating
   clocks below the round trip time between the system. In case of
   specific out of sync event Linux can opt-in to accept sync checks.
   This will result in non-monotonic jumps of the TOD clock, which
   Linux will correct via time offsets to keep the wall clock time
   monotonic. Now: KVM guests also base their time on the host TOD,
   so we need to fixup the offset for them as well.
2015-08-13 11:51:50 +02:00
Marc Zyngier f120cd6533 KVM: arm/arm64: timer: Allow the timer to control the active state
In order to remove the crude hack where we sneak the masked bit
into the timer's control register, make use of the phys_irq_map
API control the active state of the interrupt.

This causes some limited changes to allow for potential error
propagation.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 773299a570 KVM: arm/arm64: vgic: Prevent userspace injection of a mapped interrupt
Virtual interrupts mapped to a HW interrupt should only be triggered
from inside the kernel. Otherwise, you could end up confusing the
kernel (and the GIC's) state machine.

Rearrange the injection path so that kvm_vgic_inject_irq is
used for non-mapped interrupts, and kvm_vgic_inject_mapped_irq is
used for mapped interrupts. The latter should only be called from
inside the kernel (timer, irqfd).

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 6e84e0e067 KVM: arm/arm64: vgic: Add vgic_{get,set}_phys_irq_active
In order to control the active state of an interrupt, introduce
a pair of accessors allowing the state to be set/queried.

This only affects the logical state, and the HW state will only be
applied at world-switch time.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:26 +01:00
Marc Zyngier 08fd6461e8 KVM: arm/arm64: vgic: Allow HW interrupts to be queued to a guest
To allow a HW interrupt to be injected into a guest, we lookup the
guest virtual interrupt in the irq_phys_map list, and if we have
a match, encode both interrupts in the LR.

We also mark the interrupt as "active" at the host distributor level.

On guest EOI on the virtual interrupt, the host interrupt will be
deactivated.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:25 +01:00
Marc Zyngier 6c3d63c9a2 KVM: arm/arm64: vgic: Allow dynamic mapping of physical/virtual interrupts
In order to be able to feed physical interrupts to a guest, we need
to be able to establish the virtual-physical mapping between the two
worlds.

The mappings are kept in a set of RCU lists, indexed by virtual interrupts.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:25 +01:00
Marc Zyngier 7a67b4b7e0 KVM: arm/arm64: vgic: Relax vgic_can_sample_irq for edge IRQs
We only set the irq_queued flag for level interrupts, meaning
that "!vgic_irq_is_queued(vcpu, irq)" is a good enough predicate
for all interrupts.

This will allow us to inject edge HW interrupts, for which the
state ACTIVE+PENDING is not allowed.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:25 +01:00
Marc Zyngier fb182cf845 KVM: arm/arm64: vgic: Allow HW irq to be encoded in LR
Now that struct vgic_lr supports the LR_HW bit and carries a hwirq
field, we can encode that information into the list registers.

This patch provides implementations for both GICv2 and GICv3.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:24 +01:00
Marc Zyngier 32d2d8010c KVM: arm/arm64: vgic: Convert struct vgic_lr to use bitfields
As we're about to cram more information in the vgic_lr structure
(HW interrupt number and additional state information), we switch
to a layout similar to the HW's:

- use bitfields to save space (we don't need more than 10 bits
  to represent the irq numbers)
- source CPU and HW interrupt can share the same field, as
  a SGI doesn't have a physical line.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:24 +01:00
Marc Zyngier abdf584383 arm/arm64: KVM: Move vgic handling to a non-preemptible section
As we're about to introduce some serious GIC-poking to the vgic code,
it is important to make sure that we're going to poke the part of
the GIC that belongs to the CPU we're about to run on (otherwise,
we'd end up with some unexpected interrupts firing)...

Introducing a non-preemptible section in kvm_arch_vcpu_ioctl_run
prevents the problem from occuring.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:23 +01:00
Marc Zyngier 9a99d05070 arm/arm64: KVM: Fix ordering of timer/GIC on guest entry
As we now inject the timer interrupt when we're about to enter
the guest, it makes a lot more sense to make sure this happens
before the vgic code queues the pending interrupts.

Otherwise, we get the interrupt on the following exit, which is
not great for latency (and leads to all kind of bizarre issues
when using with active interrupts at the HW level).

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-08-12 11:28:23 +01:00
Vladimir Murzin 48f8bd5775 arm64: KVM: remove remaining reference to vgic_sr_vectors
Since commit 8a14849 (arm64: KVM: Switch vgic save/restore to
alternative_insn) vgic_sr_vectors is not used anymore, so remove
remaining leftovers and kill the structure.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:23 +01:00
Suzuki K. Poulose bca556ac46 arm64/kvm: Add generic v8 KVM target
This patch adds a generic ARM v8 KVM target cpu type for use
by the new CPUs which eventualy ends up using the common sys_reg
table. For backward compatibility the existing targets have been
preserved. Any new target CPU that can be covered by generic v8
sys_reg tables should make use of the new generic target.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Marc Zyngier <Marc.Zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-08-12 11:28:22 +01:00
Wei Huang b6bb424b40 KVM: x86/vPMU: Fix unnecessary signed extension for AMD PERFCTRn
According to AMD programmer's manual, AMD PERFCTRn is 64-bit MSR which,
unlike Intel perf counters, doesn't require signed extension. This
patch removes the unnecessary conversion in SVM vPMU code when PERFCTRn
is being updated.

Signed-off-by: Wei Huang <wei@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-11 15:19:41 +02:00
Nicholas Krause 603242a88a kvm: x86: Fix error handling in the function kvm_lapic_sync_from_vapic
This fixes error handling in the function kvm_lapic_sync_from_vapic
by checking if the call to kvm_read_guest_cached has returned a
error code to signal to its caller the call to this function has
failed and due to this we must immediately return to the caller
of kvm_lapic_sync_from_vapic to avoid incorrectly call apic_set_tpc
if a error has occurred here.

Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-11 15:11:05 +02:00
Nicholas Krause 152b28392a KVM: s390: Fix assumption that kvm_set_irq_routing is always run successfully
This fixes the assumption that kvm_set_irq_routing is always run
successfully by instead making it equal to the variable r which
we use for returning in the function kvm_arch_vm_ioctl instead
of making r equal to zero when calling this particular function
and incorrectly making the caller of kvm_arch_vm_ioctl think
the function has run successfully.

Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
Message-Id: <1438880754-27149-1-git-send-email-xerofoify@gmail.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-08-07 12:15:23 +02:00
Xiao Guangrong f735d4af4b KVM: VMX: drop ept misconfig check
The logic used to check ept misconfig is completely contained in common
reserved bits check for sptes, so it can be removed

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:26 +02:00
Xiao Guangrong 47ab875169 KVM: MMU: fully check zero bits for sptes
The #PF with PFEC.RSV = 1 is designed to speed MMIO emulation, however,
it is possible that the RSV #PF is caused by real BUG by mis-configure
shadow page table entries

This patch enables full check for the zero bits on shadow page table
entries (which includes not only bits reserved by the hardware, but also
bits that will never be set in the SPTE), then dump the shadow page table
hierarchy.

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:26 +02:00
Xiao Guangrong d625b155d2 KVM: MMU: introduce is_shadow_zero_bits_set()
We have the same data struct to check reserved bits on guest page tables
and shadow page tables, split is_rsvd_bits_set() so that the logic can be
shared between these two paths

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:25 +02:00
Xiao Guangrong c258b62b26 KVM: MMU: introduce the framework to check zero bits on sptes
We have abstracted the data struct and functions which are used to check
reserved bit on guest page tables, now we extend the logic to check
zero bits on shadow page tables

The zero bits on sptes include not only reserved bits on hardware but also
the bits that SPTEs willnever use.  For example, shadow pages will never
use GB pages unless the guest uses them too.

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:24 +02:00
Xiao Guangrong 81b8eebbc3 KVM: MMU: split reset_rsvds_bits_mask_ept
Since shadow ept page tables and Intel nested guest page tables have the
same format, split reset_rsvds_bits_mask_ept so that the logic can be
reused by later patches which check zero bits on sptes

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:24 +02:00
Xiao Guangrong 6dc98b868b KVM: MMU: split reset_rsvds_bits_mask
Since softmmu & AMD nested shadow page tables and guest page tables have
the same format, split reset_rsvds_bits_mask so that the logic can be
reused by later patches which check zero bits on sptes

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:23 +02:00
Xiao Guangrong a0a64f50aa KVM: MMU: introduce rsvd_bits_validate
These two fields, rsvd_bits_mask and bad_mt_xwr, in "struct kvm_mmu" are
used to check if reserved bits set on guest ptes, move them to a data
struct so that the approach can be applied to check host shadow page
table entries as well

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:23 +02:00
Xiao Guangrong d2b0f98125 KVM: MMU: move FNAME(is_rsvd_bits_set) to mmu.c
FNAME(is_rsvd_bits_set) does not depend on guest mmu mode, move it
to mmu.c to stop being compiled multiple times

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:22 +02:00
Xiao Guangrong 6f691251c0 KVM: MMU: fix validation of mmio page fault
We got the bug that qemu complained with "KVM: unknown exit, hardware
reason 31" and KVM shown these info:
[84245.284948] EPT: Misconfiguration.
[84245.285056] EPT: GPA: 0xfeda848
[84245.285154] ept_misconfig_inspect_spte: spte 0x5eaef50107 level 4
[84245.285344] ept_misconfig_inspect_spte: spte 0x5f5fadc107 level 3
[84245.285532] ept_misconfig_inspect_spte: spte 0x5141d18107 level 2
[84245.285723] ept_misconfig_inspect_spte: spte 0x52e40dad77 level 1

This is because we got a mmio #PF and the handler see the mmio spte becomes
normal (points to the ram page)

However, this is valid after introducing fast mmio spte invalidation which
increases the generation-number instead of zapping mmio sptes, a example
is as follows:
1. QEMU drops mmio region by adding a new memslot
2. invalidate all mmio sptes
3.

        VCPU 0                        VCPU 1
    access the invalid mmio spte
                            access the region originally was MMIO before
                            set the spte to the normal ram map

    mmio #PF
    check the spte and see it becomes normal ram mapping !!!

This patch fixes the bug just by dropping the check in mmio handler, it's
good for backport. Full check will be introduced in later patches

Reported-by: Pavel Shirshov <ru.pchel@gmail.com>
Tested-by: Pavel Shirshov <ru.pchel@gmail.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:21 +02:00
Alex Williamson 9c33ae0c61 KVM: MTRR: Use default type for non-MTRR-covered gfn before WARN_ON
The patch was munged on commit to re-order these tests resulting in
excessive warnings when trying to do device assignment.  Return to
original ordering: https://lkml.org/lkml/2015/7/15/769

Fixes: 3e5d2fdced ("KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:21 +02:00
Fan Zhang fdf036507f KVM: s390: host STP toleration for VMs
If the host has STP enabled, the TOD of the host will be changed during
synchronization phases. These are performed during a stop_machine() call.

As the guest TOD is based on the host TOD, we have to make sure that:
- no VCPU is in the SIE (implicitly guaranteed via stop_machine())
- manual guest TOD calculations are not affected

"Epoch" is the guest TOD clock delta to the host TOD clock. We have to
adjust that value during the STP synchronization and make sure that code
that accesses the epoch won't get interrupted in between (via disabling
preemption).

Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-08-04 14:38:37 +02:00
Paolo Bonzini 71ba994c94 KVM: x86: clean/fix memory barriers in irqchip_in_kernel
The memory barriers are trying to protect against concurrent RCU-based
interrupt injection, but the IRQ routing table is not valid at the time
kvm->arch.vpic is written.  Fix this by writing kvm->arch.vpic last.
kvm_destroy_pic then need not set kvm->arch.vpic to NULL; modify it
to take a struct kvm_pic* and reuse it if the IOAPIC creation fails.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-30 16:02:56 +02:00
Paolo Bonzini dd489240a2 KVM: document memory barriers for kvm->vcpus/kvm->online_vcpus
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-30 16:02:54 +02:00
Paolo Bonzini c847fe8895 KVM: x86: remove unnecessary memory barriers for shared MSRs
There is no smp_rmb matching the smp_wmb.  shared_msr_update is called from
hardware_enable, which in turn is called via on_each_cpu.  on_each_cpu
and must imply a read memory barrier (on x86 the rmb is achieved simply
through asm volatile in native_apic_mem_write).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-29 14:27:23 +02:00