Commit Graph

321 Commits

Author SHA1 Message Date
Andrew Jones
7e44e4495a x86: kvm: rate-limit global clock updates
When we update a vcpu's local clock it may pick up an NTP correction.
We can't wait an indeterminate amount of time for other vcpus to pick
up that correction, so commit 0061d53daf introduced a global clock
update. However, we can't request a global clock update on every vcpu
load either (which is what happens if the tsc is marked as unstable).
The solution is to rate-limit the global clock updates. Marcelo
calculated that we should delay the global clock updates no more
than 0.1s as follows:

Assume an NTP correction c is applied to one vcpu, but not the other,
then in n seconds the delta of the vcpu system_timestamps will be
c * n. If we assume a correction of 500ppm (worst-case), then the two
vcpus will diverge 50us in 0.1s, which is a considerable amount.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-03-04 11:50:47 +01:00
Liu, Jinsong
da8999d318 KVM: x86: Intel MPX vmx and msr handle
From caddc009a6d2019034af8f2346b2fd37a81608d0 Mon Sep 17 00:00:00 2001
From: Liu Jinsong <jinsong.liu@intel.com>
Date: Mon, 24 Feb 2014 18:11:11 +0800
Subject: [PATCH v5 1/3] KVM: x86: Intel MPX vmx and msr handle

This patch handle vmx and msr of Intel MPX feature.

Signed-off-by: Xudong Hao <xudong.hao@intel.com>
Signed-off-by: Liu Jinsong <jinsong.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-02-24 12:14:00 +01:00
Marcelo Tosatti
4f34d683e5 KVM: x86: remove unused last_kernel_ns variable
Remove unused last_kernel_ns variable.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-02-04 04:20:42 +01:00
Jan Kiszka
73aaf249ee KVM: SVM: Fix reading of DR6
In contrast to VMX, SVM dose not automatically transfer DR6 into the
VCPU's arch.dr6. So if we face a DR6 read, we must consult a new vendor
hook to obtain the current value. And as SVM now picks the DR6 state
from its VMCB, we also need a set callback in order to write updates of
DR6 back.

Fixes a regression of 020df0794f.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-01-17 10:22:10 +01:00
Vadim Rozenfeld
e984097b55 add support for Hyper-V reference time counter
Signed-off: Peter Lieven <pl@kamp.de>
Signed-off: Gleb Natapov
Signed-off: Vadim Rozenfeld <vrozenfe@redhat.com>

After some consideration I decided to submit only Hyper-V reference
counters support this time. I will submit iTSC support as a separate
patch as soon as it is ready.

v1 -> v2
1. mark TSC page dirty as suggested by
    Eric Northup <digitaleric@google.com> and Gleb
2. disable local irq when calling get_kernel_ns,
    as it was done by Peter Lieven <pl@amp.de>
3. move check for TSC page enable from second patch
    to this one.

v3 -> v4
    Get rid of ref counter offset.

v4 -> v5
    replace __copy_to_user with kvm_write_guest
    when updateing iTSC page.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-01-17 10:22:08 +01:00
Josh Triplett
a890b6fefd kvm: Delete prototype for non-existent function kvm_check_iopl
The prototype for kvm_check_iopl appeared in commit
f850e2e603 ("KVM: x86 emulator: Check IOPL
level during io instruction emulation"), but the function never actually
existed.  Remove the prototype.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-11-06 11:07:09 +02:00
Josh Triplett
35a5121b58 kvm: Delete prototype for non-existent function complete_pio
complete_pio ceased to exist in commit
7972995b0c ("KVM: x86 emulator: Move
string pio emulation into emulator.c"), but the prototype remained.
Remove its prototype.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-11-06 11:06:32 +02:00
Alex Williamson
e0f0bbc527 kvm: Create non-coherent DMA registeration
We currently use some ad-hoc arch variables tied to legacy KVM device
assignment to manage emulation of instructions that depend on whether
non-coherent DMA is present.  Create an interface for this, adapting
legacy KVM device assignment and adding VFIO via the KVM-VFIO device.
For now we assume that non-coherent DMA is possible any time we have a
VFIO group.  Eventually an interface can be developed as part of the
VFIO external user interface to query the coherency of a group.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30 19:02:23 +01:00
Alex Williamson
d96eb2c6f4 kvm/x86: Convert iommu_flags to iommu_noncoherent
Default to operating in coherent mode.  This simplifies the logic when
we switch to a model of registering and unregistering noncoherent I/O
with KVM.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30 19:02:13 +01:00
Christoffer Dall
6d9d41e574 KVM: Move gfn_to_index to x86 specific code
The gfn_to_index function relies on huge page defines which either may
not make sense on systems that don't support huge pages or are defined
in an unconvenient way for other architectures.  Since this is
x86-specific, move the function to arch/x86/include/asm/kvm_host.h.

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-14 10:11:44 +03:00
Paolo Bonzini
8a3c1a3347 KVM: mmu: change useless int return types to void
kvm_mmu initialization is mostly filling in function pointers, there is
no way for it to fail.  Clean up unused return values.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-03 15:44:02 +03:00
Paolo Bonzini
d8d173dab2 KVM: mmu: remove uninteresting MMU "new_cr3" callbacks
The new_cr3 MMU callback has been a wrapper for mmu_free_roots since commit
e676505 (KVM: MMU: Force cr3 reload with two dimensional paging on mov
cr3 emulation, 2012-07-08).

The commit message mentioned that "mmu_free_roots() is somewhat of an overkill,
but fixing that is more complicated and will be done after this minimal fix".
One year has passed, and no one really felt the need to do a different fix.
Wrap the call with a kvm_mmu_new_cr3 function for clarity, but remove the
callback.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-03 15:43:59 +03:00
Paolo Bonzini
206260941f KVM: mmu: remove uninteresting MMU "free" callbacks
The free MMU callback has been a wrapper for mmu_free_roots since mmu_free_roots
itself was introduced (commit 17ac10a, [PATCH] KVM: MU: Special treatment
for shadow pae root pages, 2007-01-05), and has always been the same for all
MMU cases.  Remove the indirection as it is useless.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-03 15:43:56 +03:00
Paolo Bonzini
4344ee981e KVM: x86: only copy XSAVE state for the supported features
This makes the interface more deterministic for userspace, which can expect
(after configuring only the features it supports) to get exactly the same
state from the kernel, independent of the host CPU and kernel version.

Suggested-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-03 12:29:09 +03:00
Paolo Bonzini
d7876f1be4 KVM: x86: prevent setting unsupported XSAVE states
A guest can still attempt to save and restore XSAVE states even if they
have been masked in CPUID leaf 0Dh.  This usually is not visible to
the guest, but is still wrong: "Any attempt to set a reserved bit (as
determined by the contents of EAX and EDX after executing CPUID with
EAX=0DH, ECX= 0H) in XCR0 for a given processor will result in a #GP
exception".

The patch also performs the same checks as __kvm_set_xcr in KVM_SET_XSAVE.
This catches migration from newer to older kernel/processor before the
guest starts running.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-03 12:29:07 +03:00
Srivatsa Vaddagiri
6aef266c6e kvm hypervisor : Add a hypercall to KVM hypervisor to support pv-ticketlocks
kvm_hc_kick_cpu allows the calling vcpu to kick another vcpu out of halt state.
the presence of these hypercalls is indicated to guest via
kvm_feature_pv_unhalt.

Fold pv_unhalt flag into GET_MP_STATE ioctl to aid migration
During migration, any vcpu that got kicked but did not become runnable
(still in halted state) should be runnable after migration.

Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com>
[Raghu: Apic related changes, folding pvunhalted into vcpu_runnable
 Added flags for future use (suggested by Gleb)]
[ Raghu: fold pv_unhalt flag as suggested by Eric Northup]
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Acked-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-26 12:47:09 +03:00
Yang Zhang
25d92081ae nEPT: Add nEPT violation/misconfigration support
Inject nEPT fault to L1 guest. This patch is original from Xinhao.

Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Jun Nakajima <jun.nakajima@intel.com>
Signed-off-by: Xinhao Xu <xinhao.xu@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-08-07 15:57:40 +02:00
Paolo Bonzini
ac0a48c39a KVM: x86: rename EMULATE_DO_MMIO
The next patch will reuse it for other userspace exits than MMIO,
namely debug events.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-29 09:01:14 +02:00
Andi Kleen
103af0a987 perf, kvm: Support the in_tx/in_tx_cp modifiers in KVM arch perfmon emulation v5
[KVM maintainers:
The underlying support for this is in perf/core now. So please merge
this patch into the KVM tree.]

This is not arch perfmon, but older CPUs will just ignore it. This makes
it possible to do at least some TSX measurements from a KVM guest

v2: Various fixes to address review feedback
v3: Ignore the bits when no CPUID. No #GP. Force raw events with TSX bits.
v4: Use reserved bits for #GP
v5: Remove obsolete argument
Acked-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-19 18:24:45 +02:00
Linus Torvalds
fe489bf450 KVM fixes for 3.11
On the x86 side, there are some optimizations and documentation updates.
 The big ARM/KVM change for 3.11, support for AArch64, will come through
 Catalin Marinas's tree.  s390 and PPC have misc cleanups and bugfixes.
 
 There is a conflict due to "s390/pgtable: fix ipte notify bit" having
 entered 3.10 through Martin Schwidefsky's s390 tree.  This pull request
 has additional changes on top, so this tree's version is the correct one.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "On the x86 side, there are some optimizations and documentation
  updates.  The big ARM/KVM change for 3.11, support for AArch64, will
  come through Catalin Marinas's tree.  s390 and PPC have misc cleanups
  and bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (87 commits)
  KVM: PPC: Ignore PIR writes
  KVM: PPC: Book3S PR: Invalidate SLB entries properly
  KVM: PPC: Book3S PR: Allow guest to use 1TB segments
  KVM: PPC: Book3S PR: Don't keep scanning HPTEG after we find a match
  KVM: PPC: Book3S PR: Fix invalidation of SLB entry 0 on guest entry
  KVM: PPC: Book3S PR: Fix proto-VSID calculations
  KVM: PPC: Guard doorbell exception with CONFIG_PPC_DOORBELL
  KVM: Fix RTC interrupt coalescing tracking
  kvm: Add a tracepoint write_tsc_offset
  KVM: MMU: Inform users of mmio generation wraparound
  KVM: MMU: document fast invalidate all mmio sptes
  KVM: MMU: document fast invalidate all pages
  KVM: MMU: document fast page fault
  KVM: MMU: document mmio page fault
  KVM: MMU: document write_flooding_count
  KVM: MMU: document clear_spte_count
  KVM: MMU: drop kvm_mmu_zap_mmio_sptes
  KVM: MMU: init kvm generation close to mmio wrap-around value
  KVM: MMU: add tracepoint for check_mmio_spte
  KVM: MMU: fast invalidate all mmio sptes
  ...
2013-07-03 13:21:40 -07:00
Xiao Guangrong
f6f8adeef5 KVM: MMU: document fast invalidate all pages
Document it to Documentation/virtual/kvm/mmu.txt

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-06-27 14:20:47 +03:00
Xiao Guangrong
0cbf8e437b KVM: MMU: document write_flooding_count
Document write_flooding_count to Documentation/virtual/kvm/mmu.txt

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-06-27 14:20:43 +03:00
Xiao Guangrong
accaefe07d KVM: MMU: document clear_spte_count
Document it to Documentation/virtual/kvm/mmu.txt

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-06-27 14:20:42 +03:00
Xiao Guangrong
a8eca9dcc6 KVM: MMU: drop kvm_mmu_zap_mmio_sptes
Drop kvm_mmu_zap_mmio_sptes and use kvm_mmu_invalidate_zap_all_pages
instead to handle mmio generation number overflow

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-06-27 14:20:40 +03:00
Xiao Guangrong
f8f559422b KVM: MMU: fast invalidate all mmio sptes
This patch tries to introduce a very simple and scale way to invalidate
all mmio sptes - it need not walk any shadow pages and hold mmu-lock

KVM maintains a global mmio valid generation-number which is stored in
kvm->memslots.generation and every mmio spte stores the current global
generation-number into his available bits when it is created

When KVM need zap all mmio sptes, it just simply increase the global
generation-number. When guests do mmio access, KVM intercepts a MMIO #PF
then it walks the shadow page table and get the mmio spte. If the
generation-number on the spte does not equal the global generation-number,
it will go to the normal #PF handler to update the mmio spte

Since 19 bits are used to store generation-number on mmio spte, we zap all
mmio sptes when the number is round

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-06-27 14:20:36 +03:00
H. Peter Anvin
afcbf13fa6 x86: Rename X86_CR4_RDWRGSFS to X86_CR4_FSGSBASE
Rename X86_CR4_RDWRGSFS to X86_CR4_FSGSBASE to match the SDM.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Link: http://lkml.kernel.org/n/tip-buq1evi5dpykxx7ak6amaam0@git.kernel.org
2013-06-25 16:26:06 -07:00
Xiao Guangrong
365c886860 KVM: MMU: reclaim the zapped-obsolete page first
As Marcelo pointed out that
| "(retention of large number of pages while zapping)
| can be fatal, it can lead to OOM and host crash"

We introduce a list, kvm->arch.zapped_obsolete_pages, to link all
the pages which are deleted from the mmu cache but not actually
freed. When page reclaiming is needed, we always zap this kind of
pages first.

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-05 12:33:33 +03:00
Xiao Guangrong
5304b8d37c KVM: MMU: fast invalidate all pages
The current kvm_mmu_zap_all is really slow - it is holding mmu-lock to
walk and zap all shadow pages one by one, also it need to zap all guest
page's rmap and all shadow page's parent spte list. Particularly, things
become worse if guest uses more memory or vcpus. It is not good for
scalability

In this patch, we introduce a faster way to invalidate all shadow pages.
KVM maintains a global mmu invalid generation-number which is stored in
kvm->arch.mmu_valid_gen and every shadow page stores the current global
generation-number into sp->mmu_valid_gen when it is created

When KVM need zap all shadow pages sptes, it just simply increase the
global generation-number then reload root shadow pages on all vcpus.
Vcpu will create a new shadow page table according to current kvm's
generation-number. It ensures the old pages are not used any more.
Then the obsolete pages (sp->mmu_valid_gen != kvm->arch.mmu_valid_gen)
are zapped by using lock-break technique

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-05 12:32:33 +03:00
Jan Kiszka
03b28f8133 KVM: x86: Account for failing enable_irq_window for NMI window request
With VMX, enable_irq_window can now return -EBUSY, in which case an
immediate exit shall be requested before entering the guest. Account for
this also in enable_nmi_window which uses enable_irq_window in absence
of vnmi support, e.g.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-05-02 22:17:38 -03:00
Chegu Vinod
cbf6435858 KVM: x86: Increase the "hard" max VCPU limit
KVM guests today use 8bit APIC ids allowing for 256 ID's. Reserving one
ID for Broadcast interrupts should leave 255 ID's. In case of KVM there
is no need for reserving another ID for IO-APIC so the hard max limit for
VCPUS can be increased from 254 to 255. (This was confirmed by Gleb Natapov
http://article.gmane.org/gmane.comp.emulators.kvm.devel/99713  )

Signed-off-by: Chegu Vinod <chegu_vinod@hp.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-28 13:17:48 +03:00
Gleb Natapov
064d1afaa5 Merge git://github.com/agraf/linux-2.6.git kvm-ppc-next into queue 2013-04-28 12:50:07 +03:00
Jan Kiszka
730dca42c1 KVM: x86: Rework request for immediate exit
The VMX implementation of enable_irq_window raised
KVM_REQ_IMMEDIATE_EXIT after we checked it in vcpu_enter_guest. This
caused infinite loops on vmentry. Fix it by letting enable_irq_window
signal the need for an immediate exit via its return value and drop
KVM_REQ_IMMEDIATE_EXIT.

This issue only affects nested VMX scenarios.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-28 12:44:18 +03:00
Alexander Graf
8175e5b79c KVM: Add KVM_IRQCHIP_NUM_PINS in addition to KVM_IOAPIC_NUM_PINS
The concept of routing interrupt lines to an irqchip is nothing
that is IOAPIC specific. Every irqchip has a maximum number of pins
that can be linked to irq lines.

So let's add a new define that allows us to reuse generic code for
non-IOAPIC platforms.

Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2013-04-26 20:27:13 +02:00
Jan Kiszka
384bb78327 KVM: nVMX: Validate EFER values for VM_ENTRY/EXIT_LOAD_IA32_EFER
As we may emulate the loading of EFER on VM-entry and VM-exit, implement
the checks that VMX performs on the guest and host values on vmlaunch/
vmresume. Factor out kvm_valid_efer for this purpose which checks for
set reserved bits.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-22 12:53:42 +03:00
Yang Zhang
a20ed54d6e KVM: VMX: Add the deliver posted interrupt algorithm
Only deliver the posted interrupt when target vcpu is running
and there is no previous interrupt pending in pir.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-04-16 16:32:40 -03:00
Yang Zhang
a547c6db4d KVM: VMX: Enable acknowledge interupt on vmexit
The "acknowledge interrupt on exit" feature controls processor behavior
for external interrupt acknowledgement. When this control is set, the
processor acknowledges the interrupt controller to acquire the
interrupt vector on VM exit.

After enabling this feature, an interrupt which arrived when target cpu is
running in vmx non-root mode will be handled by vmx handler instead of handler
in idt. Currently, vmx handler only fakes an interrupt stack and jump to idt
table to let real handler to handle it. Further, we will recognize the interrupt
and only delivery the interrupt which not belong to current vcpu through idt table.
The interrupt which belonged to current vcpu will be handled inside vmx handler.
This will reduce the interrupt handle cost of KVM.

Also, interrupt enable logic is changed if this feature is turnning on:
Before this patch, hypervior call local_irq_enable() to enable it directly.
Now IF bit is set on interrupt stack frame, and will be enabled on a return from
interrupt handler if exterrupt interrupt exists. If no external interrupt, still
call local_irq_enable() to enable it.

Refer to Intel SDM volum 3, chapter 33.2.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-04-16 16:32:39 -03:00
Gleb Natapov
991eebf9f8 KVM: VMX: do not try to reexecute failed instruction while emulating invalid guest state
During invalid guest state emulation vcpu cannot enter guest mode to try
to reexecute instruction that emulator failed to emulate, so emulation
will happen again and again.  Prevent that by telling the emulator that
instruction reexecution should not be attempted.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-14 09:44:17 +03:00
Geoff Levand
8b415dcd76 KVM: Move kvm_rebooting declaration out of x86
The variable kvm_rebooting is a common kvm variable, so move its
declaration from arch/x86/include/asm/kvm_host.h to
include/asm/kvm_host.h.

Fixes this sparse warning when building on arm64:

  virt/kvm/kvm_main.c⚠️ symbol 'kvm_rebooting' was not declared. Should it be static?

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-08 13:02:09 +03:00
Geoff Levand
fc1b74925f KVM: Move vm_list kvm_lock declarations out of x86
The variables vm_list and kvm_lock are common to all architectures, so
move the declarations from arch/x86/include/asm/kvm_host.h to
include/linux/kvm_host.h.

Fixes sparse warnings like these when building for arm64:

  virt/kvm/kvm_main.c: warning: symbol 'kvm_lock' was not declared. Should it be static?
  virt/kvm/kvm_main.c: warning: symbol 'vm_list' was not declared. Should it be static?

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-08 13:02:00 +03:00
Paolo Bonzini
afd80d85ae pmu: prepare for migration support
In order to migrate the PMU state correctly, we need to restore the
values of MSR_CORE_PERF_GLOBAL_STATUS (a read-only register) and
MSR_CORE_PERF_GLOBAL_OVF_CTRL (which has side effects when written).
We also need to write the full 40-bit value of the performance counter,
which would only be possible with a v3 architectural PMU's full-width
counter MSRs.

To distinguish host-initiated writes from the guest's, pass the
full struct msr_data to kvm_pmu_set_msr.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-04-02 17:42:44 +03:00
Marcelo Tosatti
2ae33b3896 Merge remote-tracking branch 'upstream/master' into queue
Merge reason:

From: Alexander Graf <agraf@suse.de>

"Just recently this really important patch got pulled into Linus' tree for 3.9:

commit 1674400aae
Author: Anton Blanchard <anton <at> samba.org>
Date:   Tue Mar 12 01:51:51 2013 +0000

Without that commit, I can not boot my G5, thus I can't run automated tests on it against my queue.

Could you please merge kvm/next against linus/master, so that I can base my trees against that?"

* upstream/master: (653 commits)
  PCI: Use ROM images from firmware only if no other ROM source available
  sparc: remove unused "config BITS"
  sparc: delete "if !ULTRA_HAS_POPULATION_COUNT"
  KVM: Fix bounds checking in ioapic indirect register reads (CVE-2013-1798)
  KVM: x86: Convert MSR_KVM_SYSTEM_TIME to use gfn_to_hva_cache functions (CVE-2013-1797)
  KVM: x86: fix for buffer overflow in handling of MSR_KVM_SYSTEM_TIME (CVE-2013-1796)
  arm64: Kconfig.debug: Remove unused CONFIG_DEBUG_ERRORS
  arm64: Do not select GENERIC_HARDIRQS_NO_DEPRECATED
  inet: limit length of fragment queue hash table bucket lists
  qeth: Fix scatter-gather regression
  qeth: Fix invalid router settings handling
  qeth: delay feature trace
  sgy-cts1000: Remove __dev* attributes
  KVM: x86: fix deadlock in clock-in-progress request handling
  KVM: allow host header to be included even for !CONFIG_KVM
  hwmon: (lm75) Fix tcn75 prefix
  hwmon: (lm75.h) Update header inclusion
  MAINTAINERS: Remove Mark M. Hoffman
  xfs: ensure we capture IO errors correctly
  xfs: fix xfs_iomap_eof_prealloc_initial_size type
  ...

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-03-21 11:11:52 -03:00
Andy Honig
0b79459b48 KVM: x86: Convert MSR_KVM_SYSTEM_TIME to use gfn_to_hva_cache functions (CVE-2013-1797)
There is a potential use after free issue with the handling of
MSR_KVM_SYSTEM_TIME.  If the guest specifies a GPA in a movable or removable
memory such as frame buffers then KVM might continue to write to that
address even after it's removed via KVM_SET_USER_MEMORY_REGION.  KVM pins
the page in memory so it's unlikely to cause an issue, but if the user
space component re-purposes the memory previously used for the guest, then
the guest will be able to corrupt that memory.

Tested: Tested against kvmclock unit test

Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-03-19 14:17:35 -03:00
Takuya Yoshikawa
982b3394dd KVM: x86: Optimize mmio spte zapping when creating/moving memslot
When we create or move a memory slot, we need to zap mmio sptes.
Currently, zap_all() is used for this and this is causing two problems:
 - extra page faults after zapping mmu pages
 - long mmu_lock hold time during zapping mmu pages

For the latter, Marcelo reported a disastrous mmu_lock hold time during
hot-plug, which made the guest unresponsive for a long time.

This patch takes a simple way to fix these problems: do not zap mmu
pages unless they are marked mmio cached.  On our test box, this took
only 50us for the 4GB guest and we did not see ms of mmu_lock hold time
any more.

Note that we still need to do zap_all() for other cases.  So another
work is also needed: Xiao's work may be the one.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-03-14 10:21:21 +02:00
Takuya Yoshikawa
95b0430d1a KVM: MMU: Mark sp mmio cached when creating mmio spte
This will be used not to zap unrelated mmu pages when creating/moving
a memory slot later.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-03-14 10:21:10 +02:00
Jan Kiszka
66450a21f9 KVM: x86: Rework INIT and SIPI handling
A VCPU sending INIT or SIPI to some other VCPU races for setting the
remote VCPU's mp_state. When we were unlucky, KVM_MP_STATE_INIT_RECEIVED
was overwritten by kvm_emulate_halt and, thus, got lost.

This introduces APIC events for those two signals, keeping them in
kvm_apic until kvm_apic_accept_events is run over the target vcpu
context. kvm_apic_has_events reports to kvm_arch_vcpu_runnable if there
are pending events, thus if vcpu blocking should end.

The patch comes with the side effect of effectively obsoleting
KVM_MP_STATE_SIPI_RECEIVED. We still accept it from user space, but
immediately translate it to KVM_MP_STATE_INIT_RECEIVED + KVM_APIC_SIPI.
The vcpu itself will no longer enter the KVM_MP_STATE_SIPI_RECEIVED
state. That also means we no longer exit to user space after receiving a
SIPI event.

Furthermore, we already reset the VCPU on INIT, only fixing up the code
segment later on when SIPI arrives. Moreover, we fix INIT handling for
the BSP: it never enter wait-for-SIPI but directly starts over on INIT.

Tested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-03-13 16:08:10 +02:00
Jan Kiszka
57f252f229 KVM: x86: Drop unused return code from VCPU reset callback
Neither vmx nor svm nor the common part may generate an error on
kvm_vcpu_reset. So drop the return code.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-03-12 13:25:56 +02:00
Yang Zhang
c7c9c56ca2 x86, apicv: add virtual interrupt delivery support
Virtual interrupt delivery avoids KVM to inject vAPIC interrupts
manually, which is fully taken care of by the hardware. This needs
some special awareness into existing interrupr injection path:

- for pending interrupt, instead of direct injection, we may need
  update architecture specific indicators before resuming to guest.

- A pending interrupt, which is masked by ISR, should be also
  considered in above update action, since hardware will decide
  when to inject it at right time. Current has_interrupt and
  get_interrupt only returns a valid vector from injection p.o.v.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-01-29 10:48:19 +02:00
Yang Zhang
8d14695f95 x86, apicv: add virtual x2apic support
basically to benefit from apicv, we need to enable virtualized x2apic mode.
Currently, we only enable it when guest is really using x2apic.

Also, clear MSR bitmap for corresponding x2apic MSRs when guest enabled x2apic:
0x800 - 0x8ff: no read intercept for apicv register virtualization,
               except APIC ID and TMCCT which need software's assistance to
               get right value.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-01-29 10:48:06 +02:00
Xiao Guangrong
93c05d3ef2 KVM: x86: improve reexecute_instruction
The current reexecute_instruction can not well detect the failed instruction
emulation. It allows guest to retry all the instructions except it accesses
on error pfn

For example, some cases are nested-write-protect - if the page we want to
write is used as PDE but it chains to itself. Under this case, we should
stop the emulation and report the case to userspace

Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-01-21 22:58:33 -02:00
Takuya Yoshikawa
e12091ce7b KVM: Remove unused slot_bitmap from kvm_mmu_page
Not needed any more.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-01-14 11:13:58 +02:00