Commit Graph

3623 Commits

Author SHA1 Message Date
Linus Torvalds 1baa5efbeb * s390: Support for runtime instrumentation within guests,
support of 248 VCPUs.
 
 * ARM: rewrite of the arm64 world switch in C, support for
 16-bit VM identifiers.  Performance counter virtualization
 missed the boat.
 
 * x86: Support for more Hyper-V features (synthetic interrupt
 controller), MMU cleanups
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "PPC changes will come next week.

   - s390: Support for runtime instrumentation within guests, support of
     248 VCPUs.

   - ARM: rewrite of the arm64 world switch in C, support for 16-bit VM
     identifiers.  Performance counter virtualization missed the boat.

   - x86: Support for more Hyper-V features (synthetic interrupt
     controller), MMU cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (115 commits)
  kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL
  kvm/x86: Hyper-V SynIC timers tracepoints
  kvm/x86: Hyper-V SynIC tracepoints
  kvm/x86: Update SynIC timers on guest entry only
  kvm/x86: Skip SynIC vector check for QEMU side
  kvm/x86: Hyper-V fix SynIC timer disabling condition
  kvm/x86: Reorg stimer_expiration() to better control timer restart
  kvm/x86: Hyper-V unify stimer_start() and stimer_restart()
  kvm/x86: Drop stimer_stop() function
  kvm/x86: Hyper-V timers fix incorrect logical operation
  KVM: move architecture-dependent requests to arch/
  KVM: renumber vcpu->request bits
  KVM: document which architecture uses each request bit
  KVM: Remove unused KVM_REQ_KICK to save a bit in vcpu->requests
  kvm: x86: Check kvm_write_guest return value in kvm_write_wall_clock
  KVM: s390: implement the RI support of guest
  kvm/s390: drop unpaired smp_mb
  kvm: x86: fix comment about {mmu,nested_mmu}.gva_to_gpa
  KVM: x86: MMU: Use clear_page() instead of init_shadow_page_table()
  arm/arm64: KVM: Detect vGIC presence at runtime
  ...
2016-01-12 13:22:12 -08:00
Huaitong Han 45bdbcfdf2 kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL
vmx_cpuid_tries to update SECONDARY_VM_EXEC_CONTROL in the VMCS, but
it will cause a vmwrite error on older CPUs because the code does not
check for the presence of CPU_BASED_ACTIVATE_SECONDARY_CONTROLS.

This will get rid of the following trace on e.g. Core2 6600:

vmwrite error: reg 401e value 10 (err 12)
Call Trace:
[<ffffffff8116e2b9>] dump_stack+0x40/0x57
[<ffffffffa020b88d>] vmx_cpuid_update+0x5d/0x150 [kvm_intel]
[<ffffffffa01d8fdc>] kvm_vcpu_ioctl_set_cpuid2+0x4c/0x70 [kvm]
[<ffffffffa01b8363>] kvm_arch_vcpu_ioctl+0x903/0xfa0 [kvm]

Fixes: feda805fe7
Cc: stable@vger.kernel.org
Reported-by: Zdenek Kaspar <zkaspar82@gmail.com>
Signed-off-by: Huaitong Han <huaitong.han@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-12 11:42:16 +01:00
Linus Torvalds 671d5532aa Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Improved CPU ID handling code and related enhancements (Borislav
     Petkov)

   - RDRAND fix (Len Brown)"

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Replace RDRAND forced-reseed with simple sanity check
  x86/MSR: Chop off lower 32-bit value
  x86/cpu: Fix MSR value truncation issue
  x86/cpu/amd, kvm: Satisfy guest kernel reads of IC_CFG MSR
  kvm: Add accessors for guest CPU's family, model, stepping
  x86/cpu: Unify CPU family, model, stepping calculation
2016-01-11 16:46:20 -08:00
Andrey Smetanin ac3e5fcae8 kvm/x86: Hyper-V SynIC timers tracepoints
Trace the following Hyper SynIC timers events:
* periodic timer start
* one-shot timer start
* timer callback
* timer expiration and message delivery result
* timer config setup
* timer count setup
* timer cleanup

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:43 +01:00
Andrey Smetanin 18659a9cb1 kvm/x86: Hyper-V SynIC tracepoints
Trace the following Hyper SynIC events:
* set msr
* set sint irq
* ack sint
* sint irq eoi

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:43 +01:00
Andrey Smetanin f3b138c5d8 kvm/x86: Update SynIC timers on guest entry only
Consolidate updating the Hyper-V SynIC timers in a
single place: on guest entry in processing KVM_REQ_HV_STIMER
request.  This simplifies the overall logic, and makes sure
the most current state of msrs and guest clock is used for
arming the timers (to achieve that, KVM_REQ_HV_STIMER
has to be processed after KVM_REQ_CLOCK_UPDATE).

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:42 +01:00
Andrey Smetanin 7be58a6488 kvm/x86: Skip SynIC vector check for QEMU side
QEMU zero-inits Hyper-V SynIC vectors. We should allow that,
and don't reject zero values if set by the host.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:42 +01:00
Andrey Smetanin 23a3b201fd kvm/x86: Hyper-V fix SynIC timer disabling condition
Hypervisor Function Specification(HFS) doesn't require
to disable SynIC timer at timer config write if timer->count = 0.

So drop this check, this allow to load timers MSR's
during migration restore, because config are set before count
in QEMU side.

Also fix condition according to HFS doc(15.3.1):
"It is not permitted to set the SINTx field to zero for an
enabled timer. If attempted, the timer will be
marked disabled (that is, bit 0 cleared) immediately."

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:41 +01:00
Andrey Smetanin 0cdeabb118 kvm/x86: Reorg stimer_expiration() to better control timer restart
Split stimer_expiration() into two parts - timer expiration message
sending and timer restart/cleanup based on timer state(config).

This also fixes a bug where a one-shot timer message whose delivery
failed once would get lost for good.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:41 +01:00
Andrey Smetanin f808495da5 kvm/x86: Hyper-V unify stimer_start() and stimer_restart()
This will be used in future to start Hyper-V SynIC timer
in several places by one logic in one function.

Changes v2:
* drop stimer->count == 0 check inside stimer_start()
* comment stimer_start() assumptions

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:40 +01:00
Andrey Smetanin 019b9781cc kvm/x86: Drop stimer_stop() function
The function stimer_stop() is called in one place
so remove the function and replace it's call by function
content.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:40 +01:00
Andrey Smetanin 1ac1b65ac1 kvm/x86: Hyper-V timers fix incorrect logical operation
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:39 +01:00
Paolo Bonzini 2860c4b167 KVM: move architecture-dependent requests to arch/
Since the numbers now overlap, it makes sense to enumerate
them in asm/kvm_host.h rather than linux/kvm_host.h.  Functions
that refer to architecture-specific requests are also moved
to arch/.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08 19:04:36 +01:00
Nicholas Krause 1dab1345d8 kvm: x86: Check kvm_write_guest return value in kvm_write_wall_clock
This makes sure the wall clock is updated only after an odd version value
is successfully written to guest memory.

Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-07 14:51:32 +01:00
Paolo Bonzini e5e57e7a03 kvm: x86: only channel 0 of the i8254 is linked to the HPET
While setting the KVM PIT counters in 'kvm_pit_load_count', if
'hpet_legacy_start' is set, the function disables the timer on
channel[0], instead of the respective index 'channel'. This is
because channels 1-3 are not linked to the HPET.  Fix the caller
to only activate the special HPET processing for channel 0.

Reported-by: P J P <pjp@fedoraproject.org>
Fixes: 0185604c2d
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-07 13:50:38 +01:00
David Matlack 0af2593b2a kvm: x86: fix comment about {mmu,nested_mmu}.gva_to_gpa
The comment had the meaning of mmu.gva_to_gpa and nested_mmu.gva_to_gpa
swapped. Fix that, and also add some details describing how each translation
works.

Signed-off-by: David Matlack <dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-07 11:03:47 +01:00
Andrew Honig 0185604c2d KVM: x86: Reload pit counters for all channels when restoring state
Currently if userspace restores the pit counters with a count of 0
on channels 1 or 2 and the guest attempts to read the count on those
channels, then KVM will perform a mod of 0 and crash.  This will ensure
that 0 values are converted to 65536 as per the spec.

This is CVE-2015-7513.

Signed-off-by: Andy Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22 15:36:26 +01:00
Paolo Bonzini e24dea2afc KVM: MTRR: treat memory as writeback if MTRR is disabled in guest CPUID
Virtual machines can be run with CPUID such that there are no MTRRs.
In that case, the firmware will never enable MTRRs and it is obviously
undesirable to run the guest entirely with UC memory.  Check out guest
CPUID, and use WB memory if MTRR do not exist.

Cc: qemu-stable@nongnu.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22 15:29:00 +01:00
Paolo Bonzini fa7c4ebd5a KVM: MTRR: observe maxphyaddr from guest CPUID, not host
Conversion of MTRRs to ranges used the maxphyaddr from the boot CPU.
This is wrong, because var_mtrr_range's mask variable then is discontiguous
(like FF00FFFF000, where the first run of 0s corresponds to the bits
between host and guest maxphyaddr).  Instead always set up the masks
to be full 64-bit values---we know that the reserved bits at the top
are zero, and we can restore them when reading the MSR.  This way
var_mtrr_range gets a mask that just works.

Fixes: a13842dc66
Cc: qemu-stable@nongnu.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22 15:28:56 +01:00
Alexis Dambricourt a7f2d78657 KVM: MTRR: fix fixed MTRR segment look up
This fixes the slow-down of VM running with pci-passthrough, since some MTRR
range changed from MTRR_TYPE_WRBACK to MTRR_TYPE_UNCACHABLE.  Memory in the
0K-640K range was incorrectly treated as uncacheable.

Fixes: f7bfb57b3e
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561
Cc: qemu-stable@nongnu.org
Signed-off-by: Alexis Dambricourt <alexis.dambricourt@gmail.com>
[Use correct BZ for "Fixes" annotation.  - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22 15:28:37 +01:00
Takuya Yoshikawa 774926641d KVM: x86: MMU: Use clear_page() instead of init_shadow_page_table()
Not just in order to clean up the code, but to make it faster by using
enhanced instructions: the initialization became 20-30% faster on our
testing machine.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-18 19:07:45 +01:00
Andrey Smetanin 481d2bcc84 kvm/x86: Remove Hyper-V SynIC timer stopping
It's possible that guest send us Hyper-V EOM at the middle
of Hyper-V SynIC timer running, so we start processing of Hyper-V
SynIC timers in vcpu context and stop the Hyper-V SynIC timer
unconditionally:

    host                                       guest
    ------------------------------------------------------------------------------
                                           start periodic stimer
    start periodic timer
    timer expires after 15ms
    send expiration message into guest
    restart periodic timer
    timer expires again after 15 ms
    msg slot is still not cleared so
    setup ->msg_pending
(1) restart periodic timer
                                           process timer msg and clear slot
                                           ->msg_pending was set:
                                               send EOM into host
    received EOM
      kvm_make_request(KVM_REQ_HV_STIMER)

    kvm_hv_process_stimers():
        ...
        stimer_stop()
        if (time_now >= stimer->exp_time)
                stimer_expiration(stimer);

Because the timer was rearmed at (1), time_now < stimer->exp_time
and stimer_expiration is not called.  The timer then never fires.

The patch fixes such situation by not stopping Hyper-V SynIC timer
at all, because it's safe to restart it without stop in vcpu context
and timer callback always returns HRTIMER_NORESTART.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:51:22 +01:00
Paolo Bonzini 8a86aea920 KVM: vmx: detect mismatched size in VMCS read/write
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
	I am sending this as RFC because the error messages it produces are
	very ugly.  Because of inlining, the original line is lost.  The
	alternative is to change vmcs_read/write/checkXX into macros, but
	then you need to have a single huge BUILD_BUG_ON or BUILD_BUG_ON_MSG
	because multiple BUILD_BUG_ON* with the same __LINE__ are not
	supported well.
2015-12-16 18:49:47 +01:00
Paolo Bonzini 845c5b4054 KVM: VMX: fix read/write sizes of VMCS fields in dump_vmcs
This was not printing the high parts of several 64-bit fields on
32-bit kernels.  Separate from the previous one to make the patches
easier to review.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:47 +01:00
Paolo Bonzini f353105463 KVM: VMX: fix read/write sizes of VMCS fields
In theory this should have broken EPT on 32-bit kernels (due to
reading the high part of natural-width field GUEST_CR3).  Not sure
if no one noticed or the processor behaves differently from the
documentation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:46 +01:00
Li RongQing 0bcf261cc8 KVM: VMX: fix the writing POSTED_INTR_NV
POSTED_INTR_NV is 16bit, should not use 64bit write function

[ 5311.676074] vmwrite error: reg 3 value 0 (err 12)
  [ 5311.680001] CPU: 49 PID: 4240 Comm: qemu-system-i38 Tainted: G I 4.1.13-WR8.0.0.0_standard #1
  [ 5311.689343] Hardware name: Intel Corporation S2600WT2/S2600WT2, BIOS SE5C610.86B.01.01.0008.021120151325 02/11/2015
  [ 5311.699550] 00000000 00000000 e69a7e1c c1950de1 00000000 e69a7e38 fafcff45 fafebd24
  [ 5311.706924] 00000003 00000000 0000000c b6a06dfa e69a7e40 fafcff79 e69a7eb0 fafd5f57
  [ 5311.714296] e69a7ec0 c1080600 00000000 00000001 c0e18018 000001be 00000000 00000b43
  [ 5311.721651] Call Trace:
  [ 5311.722942] [<c1950de1>] dump_stack+0x4b/0x75
  [ 5311.726467] [<fafcff45>] vmwrite_error+0x35/0x40 [kvm_intel]
  [ 5311.731444] [<fafcff79>] vmcs_writel+0x29/0x30 [kvm_intel]
  [ 5311.736228] [<fafd5f57>] vmx_create_vcpu+0x337/0xb90 [kvm_intel]
  [ 5311.741600] [<c1080600>] ? dequeue_task_fair+0x2e0/0xf60
  [ 5311.746197] [<faf3b9ca>] kvm_arch_vcpu_create+0x3a/0x70 [kvm]
  [ 5311.751278] [<faf29e9d>] kvm_vm_ioctl+0x14d/0x640 [kvm]
  [ 5311.755771] [<c1129d44>] ? free_pages_prepare+0x1a4/0x2d0
  [ 5311.760455] [<c13e2842>] ? debug_smp_processor_id+0x12/0x20
  [ 5311.765333] [<c10793be>] ? sched_move_task+0xbe/0x170
  [ 5311.769621] [<c11752b3>] ? kmem_cache_free+0x213/0x230
  [ 5311.774016] [<faf29d50>] ? kvm_set_memory_region+0x60/0x60 [kvm]
  [ 5311.779379] [<c1199fa2>] do_vfs_ioctl+0x2e2/0x500
  [ 5311.783285] [<c11752b3>] ? kmem_cache_free+0x213/0x230
  [ 5311.787677] [<c104dc73>] ? __mmdrop+0x63/0xd0
  [ 5311.791196] [<c104dc73>] ? __mmdrop+0x63/0xd0
  [ 5311.794712] [<c104dc73>] ? __mmdrop+0x63/0xd0
  [ 5311.798234] [<c11a2ed7>] ? __fget+0x57/0x90
  [ 5311.801559] [<c11a2f72>] ? __fget_light+0x22/0x50
  [ 5311.805464] [<c119a240>] SyS_ioctl+0x80/0x90
  [ 5311.808885] [<c1957d30>] sysenter_do_call+0x12/0x12
  [ 5312.059280] kvm: zapping shadow pages for mmio generation wraparound
  [ 5313.678415] kvm [4231]: vcpu0 disabled perfctr wrmsr: 0xc2 data 0xffff
  [ 5313.726518] kvm [4231]: vcpu0 unhandled rdmsr: 0x570

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Cc: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:45 +01:00
Andrey Smetanin 1f4b34f825 kvm/x86: Hyper-V SynIC timers
Per Hyper-V specification (and as required by Hyper-V-aware guests),
SynIC provides 4 per-vCPU timers.  Each timer is programmed via a pair
of MSRs, and signals expiration by delivering a special format message
to the configured SynIC message slot and triggering the corresponding
synthetic interrupt.

Note: as implemented by this patch, all periodic timers are "lazy"
(i.e. if the vCPU wasn't scheduled for more than the timer period the
timer events are lost), regardless of the corresponding configuration
MSR.  If deemed necessary, the "catch up" mode (the timer period is
shortened until the timer catches up) will be implemented later.

Changes v2:
* Use remainder to calculate periodic timer expiration time

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:45 +01:00
Andrey Smetanin 765eaa0f70 kvm/x86: Hyper-V SynIC message slot pending clearing at SINT ack
The SynIC message protocol mandates that the message slot is claimed
by atomically setting message type to something other than HVMSG_NONE.
If another message is to be delivered while the slot is still busy,
message pending flag is asserted to indicate to the guest that the
hypervisor wants to be notified when the slot is released.

To make sure the protocol works regardless of where the message
sources are (kernel or userspace), clear the pending flag on SINT ACK
notification, and let the message sources compete for the slot again.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:44 +01:00
Andrey Smetanin 93bf417248 kvm/x86: Hyper-V internal helper to read MSR HV_X64_MSR_TIME_REF_COUNT
This helper will be used also in Hyper-V SynIC timers implementation.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:43 +01:00
Andrey Smetanin 0ae80384b2 kvm/x86: Added Hyper-V vcpu_to_hv_vcpu()/hv_vcpu_to_vcpu() helpers
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:42 +01:00
Andrey Smetanin e18eaeed2b kvm/x86: Rearrange func's declarations inside Hyper-V header
This rearrangement places functions declarations together
according to their functionality, so future additions
will be simplier.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16 18:49:42 +01:00
Haozhong Zhang 81b1b9ca6d KVM: VMX: Fix host initiated access to guest MSR_TSC_AUX
The current handling of accesses to guest MSR_TSC_AUX returns error if
vcpu does not support rdtscp, though those accesses are initiated by
host. This can result in the reboot failure of some versions of
QEMU. This patch fixes this issue by passing those host initiated
accesses for further handling instead.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-14 16:24:08 +01:00
Paolo Bonzini 8b89fe1f6c kvm: x86: move tracepoints outside extended quiescent state
Invoking tracepoints within kvm_guest_enter/kvm_guest_exit causes a
lockdep splat.

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-11 12:26:33 +01:00
Takuya Yoshikawa bb11c6c965 KVM: x86: MMU: Remove unused parameter parent_pte from kvm_mmu_get_page()
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-26 15:31:36 +01:00
Takuya Yoshikawa 74c4e63ab9 KVM: x86: MMU: Use for_each_rmap_spte macro instead of pte_list_walk()
As kvm_mmu_get_page() was changed so that every parent pointer would not
get into the sp->parent_ptes chain before the entry pointed to by it was
set properly, we can use the for_each_rmap_spte macro instead of
pte_list_walk().

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-26 15:31:31 +01:00
Takuya Yoshikawa 98bba23842 KVM: x86: MMU: Move parent_pte handling from kvm_mmu_get_page() to link_shadow_page()
Every time kvm_mmu_get_page() is called with a non-NULL parent_pte
argument, link_shadow_page() follows that to set the parent entry so
that the new mapping will point to the returned page table.

Moving parent_pte handling there allows to clean up the code because
parent_pte is passed to kvm_mmu_get_page() just for mark_unsync() and
mmu_page_add_parent_pte().

In addition, the patch avoids calling mark_unsync() for other parents in
the sp->parent_ptes chain than the newly added parent_pte, because they
have been there since before the current page fault handling started.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-26 15:31:24 +01:00
Takuya Yoshikawa 4700579241 KVM: x86: MMU: Move initialization of parent_ptes out from kvm_mmu_alloc_page()
Make kvm_mmu_alloc_page() do just what its name tells to do, and remove
the extra allocation error check and zero-initialization of parent_ptes:
shadow page headers allocated by kmem_cache_zalloc() are always in the
per-VCPU pools.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:27:06 +01:00
Takuya Yoshikawa 77fbbbd2f0 KVM: x86: MMU: Consolidate BUG_ON checks for reverse-mapped sptes
At some call sites of rmap_get_first() and rmap_get_next(), BUG_ON is
placed right after the call to detect unrelated sptes which must not be
found in the reverse-mapping list.

Move this check in rmap_get_first/next() so that all call sites, not
just the users of the for_each_rmap_spte() macro, will be checked the
same way.

One thing to keep in mind is that kvm_mmu_unlink_parents() also uses
rmap_get_first() to handle parent sptes.  The change will not break it
because parent sptes are present, at least until drop_parent_pte()
actually unlinks them, and not mmio-sptes.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:47 +01:00
Takuya Yoshikawa afd28fe1c9 KVM: x86: MMU: Remove is_rmap_spte() and use is_shadow_present_pte()
is_rmap_spte(), originally named is_rmap_pte(), was introduced when the
simple reverse mapping was implemented by commit cd4a4e5374
("[PATCH] KVM: MMU: Implement simple reverse mapping").  At that point,
its role was clear and only rmap_add() and rmap_remove() were using it
to select sptes that need to be reverse-mapped.

Independently of that, is_shadow_present_pte() was first introduced by
commit c7addb9020 ("KVM: Allow not-present guest page faults to
bypass kvm") to do bypass_guest_pf optimization, which does not exist
any more.

These two seem to have changed their roles somewhat, and is_rmap_spte()
just calls is_shadow_present_pte() now.

Since using both of them without clear distinction just makes the code
confusing, remove is_rmap_spte().

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:35 +01:00
Takuya Yoshikawa 029499b477 KVM: x86: MMU: Make mmu_set_spte() return emulate value
mmu_set_spte()'s code is based on the assumption that the emulate
parameter has a valid pointer value if set_spte() returns true and
write_fault is not zero.  In other cases, emulate may be NULL, so a
NULL-check is needed.

Stop passing emulate pointer and make mmu_set_spte() return the emulate
value instead to clean up this complex interface.  Prefetch functions
can just throw away the return value.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:28 +01:00
Takuya Yoshikawa fd9514572f KVM: x86: MMU: Add helper function to clear a bit in unsync child bitmap
Both __mmu_unsync_walk() and mmu_pages_clear_parents() have three line
code which clears a bit in the unsync child bitmap; the former places it
inside a loop block and uses a few goto statements to jump to it.

A new helper function, clear_unsync_child_bit(), makes the code cleaner.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:15 +01:00
Takuya Yoshikawa 7ee0e5b29d KVM: x86: MMU: Remove unused parameter of __direct_map()
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:03 +01:00
Takuya Yoshikawa 018aabb56d KVM: x86: MMU: Encapsulate the type of rmap-chain head in a new struct
New struct kvm_rmap_head makes the code type-safe to some extent.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:25:44 +01:00
Paolo Bonzini 0e3d0648bd KVM: x86: MMU: always set accessed bit in shadow PTEs
Commit 7a1638ce42 ("nEPT: Redefine EPT-specific link_shadow_page()",
2013-08-05) says:

    Since nEPT doesn't support A/D bit, we should not set those bit
    when building the shadow page table.

but this is not necessary.  Even though nEPT doesn't support A/D
bits, and hence the vmcs12 EPT pointer will never enable them,
we always use them for shadow page tables if available (see
construct_eptp in vmx.c).  So we can set the A/D bits freely
in the shadow page table.

This patch hence basically reverts commit 7a1638ce42.

Cc: Yang Zhang <yang.z.zhang@Intel.com>
Cc: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:23 +01:00
Paolo Bonzini aba2f06c07 KVM: x86: correctly print #AC in traces
Poor #AC was so unimportant until a few days ago that we were
not even tracing its name correctly.  But now it's all over
the place.

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:23 +01:00
Paolo Bonzini 46896c73c1 KVM: svm: add support for RDTSCP
RDTSCP was never supported for AMD CPUs, which nobody noticed because
Linux does not use it.  But exactly the fact that Linux does not
use it makes the implementation very simple; we can freely trash
MSR_TSC_AUX while running the guest.

Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Paolo Bonzini 9dbe6cf941 KVM: x86: expose MSR_TSC_AUX to userspace
If we do not do this, it is not properly saved and restored across
migration.  Windows notices due to its self-protection mechanisms,
and is very upset about it (blue screen of death).

Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Andrey Smetanin db3975717a kvm/x86: Hyper-V kvm exit
A new vcpu exit is introduced to notify the userspace of the
changes in Hyper-V SynIC configuration triggered by guest writing to the
corresponding MSRs.

Changes v4:
* exit into userspace only if guest writes into SynIC MSR's

Changes v3:
* added KVM_EXIT_HYPERV types and structs notes into docs

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Andrey Smetanin 5c919412fe kvm/x86: Hyper-V synthetic interrupt controller
SynIC (synthetic interrupt controller) is a lapic extension,
which is controlled via MSRs and maintains for each vCPU
 - 16 synthetic interrupt "lines" (SINT's); each can be configured to
   trigger a specific interrupt vector optionally with auto-EOI
   semantics
 - a message page in the guest memory with 16 256-byte per-SINT message
   slots
 - an event flag page in the guest memory with 16 2048-bit per-SINT
   event flag areas

The host triggers a SINT whenever it delivers a new message to the
corresponding slot or flips an event flag bit in the corresponding area.
The guest informs the host that it can try delivering a message by
explicitly asserting EOI in lapic or writing to End-Of-Message (EOM)
MSR.

The userspace (qemu) triggers interrupts and receives EOM notifications
via irqfd with resampler; for that, a GSI is allocated for each
configured SINT, and irq_routing api is extended to support GSI-SINT
mapping.

Changes v4:
* added activation of SynIC by vcpu KVM_ENABLE_CAP
* added per SynIC active flag
* added deactivation of APICv upon SynIC activation

Changes v3:
* added KVM_CAP_HYPERV_SYNIC and KVM_IRQ_ROUTING_HV_SINT notes into
docs

Changes v2:
* do not use posted interrupts for Hyper-V SynIC AutoEOI vectors
* add Hyper-V SynIC vectors into EOI exit bitmap
* Hyper-V SyniIC SINT msr write logic simplified

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Andrey Smetanin d62caabb41 kvm/x86: per-vcpu apicv deactivation support
The decision on whether to use hardware APIC virtualization used to be
taken globally, based on the availability of the feature in the CPU
and the value of a module parameter.

However, under certain circumstances we want to control it on per-vcpu
basis.  In particular, when the userspace activates HyperV synthetic
interrupt controller (SynIC), APICv has to be disabled as it's
incompatible with SynIC auto-EOI behavior.

To achieve that, introduce 'apicv_active' flag on struct
kvm_vcpu_arch, and kvm_vcpu_deactivate_apicv() function to turn APICv
off.  The flag is initialized based on the module parameter and CPU
capability, and consulted whenever an APICv-specific action is
performed.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:21 +01:00