This is the same as before:

    kvm_scale_tsc(tgt_tsc_khz)
        = tgt_tsc_khz * ratio
        = tgt_tsc_khz * user_tsc_khz / tsc_khz   (see set_tsc_khz)
        = user_tsc_khz                           (see kvm_guest_time_update)
        = vcpu->arch.virtual_tsc_khz             (see kvm_set_tsc_khz)

However, computing it through kvm_scale_tsc will make it possible
to include the NTP correction in tgt_tsc_khz.
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This refers to the desired (scaled) frequency, which is called
user_tsc_khz in the rest of the file.
Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When we take a #DB or #BP vmexit while in guest mode, we first of all
need to check if there is ongoing guest debugging that might be
interested in the event. Currently, we unconditionally leave L2 and
inject the event into L1 if it is intercepting the exceptions. That
breaks things marvelously.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

There is quite some common code in all these is_<exception>() helpers.
Factor it out before adding even more of them.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Different pieces of code checked for vcpu->arch.apic being (non-)NULL,
or used kvm_vcpu_has_lapic (more optimized) or lapic_in_kernel.
Replace everything with lapic_in_kernel's name and kvm_vcpu_has_lapic's
implementation.
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Do for kvm_cpu_has_pending_timer and kvm_inject_pending_timer_irqs
what the other irq.c routines have been doing.
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Usually the in-kernel APIC's existence is checked in the caller.  Do not
bother checking it again in lapic.c.
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add host irq information in trace event, so we can better understand
which irq is in posted mode.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NRadim Krcmar <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Use vector-hashing to deliver lowest-priority interrupts for
VT-d posted-interrupts. This patch extends kvm_intr_is_single_vcpu()
to support lowest-priority handling.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Use vector-hashing to deliver lowest-priority interrupts, As an
example, modern Intel CPUs in server platform use this method to
handle lowest-priority interrupts.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When the interrupt is not single destination any more, we need
to change back IRTE to remapped mode explicitly.
Signed-off-by: NFeng Wu <feng.wu@intel.com>
Reviewed-by: NRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This is similar to the existing div_frac function, but it returns the
remainder too.  Unlike div_frac, it can be used to implement long
division, e.g. (a << 64) / b for 32-bit a and b.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

To date, we have implemented two I/O usage models for persistent memory,
PMEM (a persistent "ram disk") and DAX (mmap persistent memory into
userspace).  This series adds a third, DAX-GUP, that allows DAX mappings
to be the target of direct-i/o.  It allows userspace to coordinate
DMA/RDMA from/to persistent memory.

The implementation leverages the ZONE_DEVICE mm-zone that went into
4.3-rc1 (also discussed at kernel summit) to flag pages that are owned
and dynamically mapped by a device driver.  The pmem driver, after
mapping a persistent memory range into the system memmap via
devm_memremap_pages(), arranges for DAX to distinguish pfn-only versus
page-backed pmem-pfns via flags in the new pfn_t type.

The DAX code, upon seeing a PFN_DEV+PFN_MAP flagged pfn, flags the
resulting pte(s) inserted into the process page tables with a new
_PAGE_DEVMAP flag.  Later, when get_user_pages() is walking ptes it keys
off _PAGE_DEVMAP to pin the device hosting the page range active.
Finally, get_page() and put_page() are modified to take references
against the device driver established page mapping.

Finally, this need for "struct page" for persistent memory requires
memory capacity to store the memmap array.  Given the memmap array for a
large pool of persistent may exhaust available DRAM introduce a
mechanism to allocate the memmap from persistent memory.  The new
"struct vmem_altmap *" parameter to devm_memremap_pages() enables
arch_add_memory() to use reserved pmem capacity rather than the page
allocator.

This patch (of 18):

The core has developed a need for a "pfn_t" type [1].  Move the existing
pfn_t in KVM to kvm_pfn_t [2].

[1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002199.html
[2]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002218.htmlSigned-off-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: NChristoffer Dall <christoffer.dall@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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: feda805f
Cc: stable@vger.kernel.org
Reported-by: NZdenek Kaspar <zkaspar82@gmail.com>
Signed-off-by: NHuaitong Han <huaitong.han@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey 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: NPaolo Bonzini <pbonzini@redhat.com>

Trace the following Hyper SynIC events:
* set msr
* set sint irq
* ack sint
* sint irq eoi
Signed-off-by: NAndrey 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: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

The function stimer_stop() is called in one place
so remove the function and replace it's call by function
content.
Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

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: NPaolo Bonzini <pbonzini@redhat.com>

This makes sure the wall clock is updated only after an odd version value
is successfully written to guest memory.
Signed-off-by: NNicholas Krause <xerofoify@gmail.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NP J P <pjp@fedoraproject.org>
Fixes: 0185604cSigned-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NDavid Matlack <dmatlack@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This reverts commit 677a73a9. This patch was not meant to be merged and
has issues. Revert it.
Requested-by: NAndy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

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: NAndy Honig <ahonig@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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=107561Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: a13842dc
Cc: qemu-stable@nongnu.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: f7bfb57b
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561
Cc: qemu-stable@nongnu.org
Signed-off-by: NAlexis Dambricourt <alexis.dambricourt@gmail.com>
[Use correct BZ for "Fixes" annotation.  - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey 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: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo 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.

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: NPaolo Bonzini <pbonzini@redhat.com>

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: NPaolo Bonzini <pbonzini@redhat.com>

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: NLi RongQing <roy.qing.li@gmail.com>
Cc: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>

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: NAndrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: NRoman 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: NPaolo Bonzini <pbonzini@redhat.com>