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In kvm_lapic_sync_from_vapic and kvm_lapic_sync_to_vapic there is the
potential to corrupt kernel memory if userspace provides an address that
is at the end of a page. This patches concerts those functions to use
kvm_write_guest_cached and kvm_read_guest_cached. It also checks the
vapic_address specified by userspace during ioctl processing and returns
an error to userspace if the address is not a valid GPA.
This is generally not guest triggerable, because the required write is
done by firmware that runs before the guest. Also, it only affects AMD
processors and oldish Intel that do not have the FlexPriority feature
(unless you disable FlexPriority, of course; then newer processors are
also affected).
Fixes: b93463aa59d6 ('KVM: Accelerated apic support')
Reported-by: Andrew Honig <ahonig@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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I noticed that srcu_read_lock/unlock both have a memory barrier,
so just by moving srcu_read_unlock earlier we can get rid of
one call to smp_mb() using smp_mb__after_srcu_read_unlock instead.
Unsurprisingly, the gain is small but measureable using the unit test
microbenchmark:
before
vmcall in the ballpark of 1410 cycles
after
vmcall in the ballpark of 1360 cycles
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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Conflicts:
arch/powerpc/include/asm/processor.h
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The loop was always using 0 as the index. This means that
any rubbish after the first element of the array went undetected.
It seems reasonable to assume that no KVM userspace did that.
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The KVM_SET_XCRS ioctl must accept anything that KVM_GET_XCRS
could return. XCR0's bit 0 is always 1 in real processors with
XSAVE, and KVM_GET_XCRS will always leave bit 0 set even if the
emulated processor does not have XSAVE. So, KVM_SET_XCRS must
ignore that bit when checking for attempts to enable unsupported
save states.
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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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>
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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>
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Call it EmulateOnUD which is exactly what we're trying to do with
vendor-specific instructions.
Rename ->only_vendor_specific_insn to something shorter, while at it.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Add a field to the current emulation context which contains the
instruction opcode length. This will streamline handling of opcodes of
different length.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Add a kvm ioctl which states which system functionality kvm emulates.
The format used is that of CPUID and we return the corresponding CPUID
bits set for which we do emulate functionality.
Make sure ->padding is being passed on clean from userspace so that we
can use it for something in the future, after the ioctl gets cast in
stone.
s/kvm_dev_ioctl_get_supported_cpuid/kvm_dev_ioctl_get_cpuid/ while at
it.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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We will use that in the later patch to find the kvm ops handler
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
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Page pinning is not mandatory in kvm async page fault processing since
after async page fault event is delivered to a guest it accesses page once
again and does its own GUP. Drop the FOLL_GET flag in GUP in async_pf
code, and do some simplifying in check/clear processing.
Suggested-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Gu zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: chai wen <chaiw.fnst@cn.fujitsu.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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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>
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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>
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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>
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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>
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In commit e935b8372cf8 ("KVM: Convert kvm_lock to raw_spinlock"),
the kvm_lock was made a raw lock. However, the kvm mmu_shrink()
function tries to grab the (non-raw) mmu_lock within the scope of
the raw locked kvm_lock being held. This leads to the following:
BUG: sleeping function called from invalid context at kernel/rtmutex.c:659
in_atomic(): 1, irqs_disabled(): 0, pid: 55, name: kswapd0
Preemption disabled at:[<ffffffffa0376eac>] mmu_shrink+0x5c/0x1b0 [kvm]
Pid: 55, comm: kswapd0 Not tainted 3.4.34_preempt-rt
Call Trace:
[<ffffffff8106f2ad>] __might_sleep+0xfd/0x160
[<ffffffff817d8d64>] rt_spin_lock+0x24/0x50
[<ffffffffa0376f3c>] mmu_shrink+0xec/0x1b0 [kvm]
[<ffffffff8111455d>] shrink_slab+0x17d/0x3a0
[<ffffffff81151f00>] ? mem_cgroup_iter+0x130/0x260
[<ffffffff8111824a>] balance_pgdat+0x54a/0x730
[<ffffffff8111fe47>] ? set_pgdat_percpu_threshold+0xa7/0xd0
[<ffffffff811185bf>] kswapd+0x18f/0x490
[<ffffffff81070961>] ? get_parent_ip+0x11/0x50
[<ffffffff81061970>] ? __init_waitqueue_head+0x50/0x50
[<ffffffff81118430>] ? balance_pgdat+0x730/0x730
[<ffffffff81060d2b>] kthread+0xdb/0xe0
[<ffffffff8106e122>] ? finish_task_switch+0x52/0x100
[<ffffffff817e1e94>] kernel_thread_helper+0x4/0x10
[<ffffffff81060c50>] ? __init_kthread_worker+0x
After the previous patch, kvm_lock need not be a raw spinlock anymore,
so change it back.
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: kvm@vger.kernel.org
Cc: gleb@redhat.com
Cc: jan.kiszka@siemens.com
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The offset to add to the hosts monotonic time, kvmclock_offset, is
calculated against the monotonic time at KVM_SET_CLOCK ioctl time.
Request a master clock update at this time, to reduce a potentially
unbounded difference between the values of the masterclock and
the clock value used to calculate kvmclock_offset.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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Support for single-step in the emulator (new in 3.12) does not work for
MMIO or PIO writes, because they are completed without returning to
the emulator. This is not worse than what we had in 3.11; still, add
comments so that the issue is not forgotten.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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Note that we are using APIC_DM_REMRD which has reserved usage.
In future if APIC_DM_REMRD usage is standardized, then we should
find some other way or go back to old method.
Suggested-by: Gleb Natapov <gleb@redhat.com>
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>
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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>
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kvm_set_cr3() attempts to check if the new cr3 is a valid guest physical
address. The problem is that with nested EPT, cr3 is an *L2* physical
address, not an L1 physical address as this test expects.
As the comment above this test explains, it isn't necessary, and doesn't
correspond to anything a real processor would do. So this patch removes it.
Note that this wrong test could have also theoretically caused problems
in nested NPT, not just in nested EPT. However, in practice, the problem
was avoided: nested_svm_vmexit()/vmrun() do not call kvm_set_cr3 in the
nested NPT case, and instead set the vmcb (and arch.cr3) directly, thus
circumventing the problem. Additional potential calls to the buggy function
are avoided in that we don't trap cr3 modifications when nested NPT is
enabled. However, because in nested VMX we did want to use kvm_set_cr3()
(as requested in Avi Kivity's review of the original nested VMX patches),
we can't avoid this problem and need to fix it.
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Nadav Har'El <nyh@il.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>
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This lets debugging work better during emulation of invalid
guest state.
This time the check is done after emulation, but before writeback
of the flags; we need to check the flags *before* execution of the
instruction, we cannot check singlestep_rip because the CS base may
have already been modified.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Conflicts:
arch/x86/kvm/x86.c
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This lets debugging work better during emulation of invalid
guest state.
The check is done before emulating the instruction, and (in the case
of guest debugging) reuses EMULATE_DO_MMIO to exit with KVM_EXIT_DEBUG.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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The next patch will reuse it for other userspace exits than MMIO,
namely debug events.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Fix read/write to IA32_FEATURE_CONTROL MSR in nested environment.
This patch simulate this MSR in nested_vmx and the default value is
0x0. BIOS should set it to 0x5 before VMXON. After setting the lock
bit, write to it will cause #GP(0).
Another QEMU patch is also needed to handle emulation of reset
and migration. Reset to vCPU should clear this MSR and migration
should reserve value of it.
This patch is based on Nadav's previous commit.
http://permalink.gmane.org/gmane.comp.emulators.kvm.devel/88478
Signed-off-by: Nadav Har'El <nyh@math.technion.ac.il>
Signed-off-by: Arthur Chunqi Li <yzt356@gmail.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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Void pointers don't need no casting, drop it.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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Now that kvm_arch_memslots_updated() catches every increment of the
memslots->generation, checking if the mmio generation has reached its
maximum value is enough.
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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This is called right after the memslots is updated, i.e. when the result
of update_memslots() gets installed in install_new_memslots(). Since
the memslots needs to be updated twice when we delete or move a memslot,
kvm_arch_commit_memory_region() does not correspond to this exactly.
In the following patch, x86 will use this new API to check if the mmio
generation has reached its maximum value, in which case mmio sptes need
to be flushed out.
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Acked-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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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
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull asm/x86 changes from Ingo Molnar:
"Misc changes, with a bigger processor-flags cleanup/reorganization by
Peter Anvin"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, asm, cleanup: Replace open-coded control register values with symbolic
x86, processor-flags: Fix the datatypes and add bit number defines
x86: Rename X86_CR4_RDWRGSFS to X86_CR4_FSGSBASE
x86, flags: Rename X86_EFLAGS_BIT1 to X86_EFLAGS_FIXED
linux/const.h: Add _BITUL() and _BITULL()
x86/vdso: Convert use of typedef ctl_table to struct ctl_table
x86: __force_order doesn't need to be an actual variable
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Add a tracepoint write_tsc_offset for tracing TSC offset change.
We want to merge ftrace's trace data of guest OSs and the host OS using
TSC for timestamp in chronological order. We need "TSC offset" values for
each guest when merge those because the TSC value on a guest is always the
host TSC plus guest's TSC offset. If we get the TSC offset values, we can
calculate the host TSC value for each guest events from the TSC offset and
the event TSC value. The host TSC values of the guest events are used when we
want to merge trace data of guests and the host in chronological order.
(Note: the trace_clock of both the host and the guest must be set x86-tsc in
this case)
This tracepoint also records vcpu_id which can be used to merge trace data for
SMP guests. A merge tool will read TSC offset for each vcpu, then the tool
converts guest TSC values to host TSC values for each vcpu.
TSC offset is stored in the VMCS by vmx_write_tsc_offset() or
vmx_adjust_tsc_offset(). KVM executes the former function when a guest boots.
The latter function is executed when kvm clock is updated. Only host can read
TSC offset value from VMCS, so a host needs to output TSC offset value
when TSC offset is changed.
Since the TSC offset is not often changed, it could be overwritten by other
frequent events while tracing. To avoid that, I recommend to use a special
instance for getting this event:
1. set a instance before booting a guest
# cd /sys/kernel/debug/tracing/instances
# mkdir tsc_offset
# cd tsc_offset
# echo x86-tsc > trace_clock
# echo 1 > events/kvm/kvm_write_tsc_offset/enable
2. boot a guest
Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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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>
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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
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Let mmio spte only use bit62 and bit63 on upper 32 bits, then bit 52 ~ bit 61
can be used for other purposes
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>
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__kvm_set_xcr function does the CPL check when set xcr. __kvm_set_xcr is
called in two flows, one is invoked by guest, call stack shown as below,
handle_xsetbv(or xsetbv_interception)
kvm_set_xcr
__kvm_set_xcr
the other one is invoked by host, for example during system reset:
kvm_arch_vcpu_ioctl
kvm_vcpu_ioctl_x86_set_xcrs
__kvm_set_xcr
The former does need the CPL check, but the latter does not.
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Haoyu <haoyu.zhang@huawei.com>
[Tweaks to commit message. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Its possible that idivl overflows (due to large delta stored in usdiff,
valid scenario).
Create an exception handler to catch the overflow exception (division by zero
is protected by vcpu->arch.virtual_tsc_khz check), and interpret it accordingly
(delta is larger than USEC_PER_SEC).
Fixes https://bugzilla.redhat.com/show_bug.cgi?id=969644
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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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>
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Replace kvm_mmu_zap_all by kvm_mmu_invalidate_zap_all_pages
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>
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It is the responsibility of kvm_mmu_zap_all that keeps the
consistent of mmu and tlbs. And it is also unnecessary after
zap all mmio sptes since no mmio spte exists on root shadow
page and it can not be cached into tlb
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>
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Quote Gleb's mail:
| Back then kvm->lock protected memslot access so code like:
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| mutex_lock(&vcpu->kvm->lock);
| kvm_mmu_zap_all(vcpu->kvm);
| mutex_unlock(&vcpu->kvm->lock);
|
| which is what 7aa81cc0 does was enough to guaranty that no vcpu will
| run while code is patched. This is no longer the case and
| mutex_lock(&vcpu->kvm->lock); is gone from that code path long time ago,
| so now kvm_mmu_zap_all() there is useless and the code is incorrect.
So we drop it and it will be fixed later
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>
|
|
kvmclock updates which are isolated to a given vcpu, such as vcpu->cpu
migration, should not allow system_timestamp from the rest of the vcpus
to remain static. Otherwise ntp frequency correction applies to one
vcpu's system_timestamp but not the others.
So in those cases, request a kvmclock update for all vcpus. The worst
case for a remote vcpu to update its kvmclock is then bounded by maximum
nohz sleep latency.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
|
|
Emulation of xcr0 writes zero guest_xcr0_loaded variable so that
subsequent VM-entry reloads CPU's xcr0 with guests xcr0 value.
However, this is incorrect because guest_xcr0_loaded variable is
read to decide whether to reload hosts xcr0.
In case the vcpu thread is scheduled out after the guest_xcr0_loaded = 0
assignment, and scheduler decides to preload FPU:
switch_to
{
__switch_to
__math_state_restore
restore_fpu_checking
fpu_restore_checking
if (use_xsave())
fpu_xrstor_checking
xrstor64 with CPU's xcr0 == guests xcr0
Fix by properly restoring hosts xcr0 during emulation of xcr0 writes.
Analyzed-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
|
|
Pull kvm updates from Gleb Natapov:
"Highlights of the updates are:
general:
- new emulated device API
- legacy device assignment is now optional
- irqfd interface is more generic and can be shared between arches
x86:
- VMCS shadow support and other nested VMX improvements
- APIC virtualization and Posted Interrupt hardware support
- Optimize mmio spte zapping
ppc:
- BookE: in-kernel MPIC emulation with irqfd support
- Book3S: in-kernel XICS emulation (incomplete)
- Book3S: HV: migration fixes
- BookE: more debug support preparation
- BookE: e6500 support
ARM:
- reworking of Hyp idmaps
s390:
- ioeventfd for virtio-ccw
And many other bug fixes, cleanups and improvements"
* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
kvm: Add compat_ioctl for device control API
KVM: x86: Account for failing enable_irq_window for NMI window request
KVM: PPC: Book3S: Add API for in-kernel XICS emulation
kvm/ppc/mpic: fix missing unlock in set_base_addr()
kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
kvm/ppc/mpic: remove users
kvm/ppc/mpic: fix mmio region lists when multiple guests used
kvm/ppc/mpic: remove default routes from documentation
kvm: KVM_CAP_IOMMU only available with device assignment
ARM: KVM: iterate over all CPUs for CPU compatibility check
KVM: ARM: Fix spelling in error message
ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
KVM: ARM: Fix API documentation for ONE_REG encoding
ARM: KVM: promote vfp_host pointer to generic host cpu context
ARM: KVM: add architecture specific hook for capabilities
ARM: KVM: perform HYP initilization for hotplugged CPUs
ARM: KVM: switch to a dual-step HYP init code
ARM: KVM: rework HYP page table freeing
ARM: KVM: enforce maximum size for identity mapped code
ARM: KVM: move to a KVM provided HYP idmap
...
|
|
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>
|
|
Fix build with CONFIG_PCI unset by linking KVM_CAP_IOMMU to
device assignment config option. It has no purpose otherwise.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
|
|
We hope to at some point deprecate KVM legacy device assignment in
favor of VFIO-based assignment. Towards that end, allow legacy
device assignment to be deconfigured.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
|
|
|
|
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>
|
|
Now that we have most irqfd code completely platform agnostic, let's move
irqfd's resample capability return to generic code as well.
Signed-off-by: Alexander Graf <agraf@suse.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
|
