Commit Graph

900999 Commits

Author SHA1 Message Date
Michael Ellerman afd313564c KVM: PPC: Book3S HV: Use RADIX_PTE_INDEX_SIZE in Radix MMU code
In kvmppc_unmap_free_pte() in book3s_64_mmu_radix.c, we use the
non-constant value PTE_INDEX_SIZE to clear a PTE page.

We can instead use the constant RADIX_PTE_INDEX_SIZE, because we know
this code will only be running when the Radix MMU is active.

Note that we already use RADIX_PTE_INDEX_SIZE for the allocation of
kvm_pte_cache.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Leonardo Bras <leonardo@linux.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-03-19 16:39:52 +11:00
Paul Mackerras cd758a9b57 KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT page fault handler
This makes the same changes in the page fault handler for HPT guests
that commits 31c8b0d069 ("KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot()
in page fault handler", 2018-03-01), 71d29f43b6 ("KVM: PPC: Book3S HV:
Don't use compound_order to determine host mapping size", 2018-09-11)
and 6579804c43 ("KVM: PPC: Book3S HV: Avoid crash from THP collapse
during radix page fault", 2018-10-04) made for the page fault handler
for radix guests.

In summary, where we used to call get_user_pages_fast() and then do
special handling for VM_PFNMAP vmas, we now call __get_user_pages_fast()
and then __gfn_to_pfn_memslot() if that fails, followed by reading the
Linux PTE to get the host PFN, host page size and mapping attributes.

This also brings in the change from SetPageDirty() to set_page_dirty_lock()
which was done for the radix page fault handler in commit c3856aeb29
("KVM: PPC: Book3S HV: Fix handling of large pages in radix page fault
handler", 2018-02-23).

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2020-03-19 16:39:52 +11:00
Paolo Bonzini 1c482452d5 KVM: s390: Features and Enhancements for 5.7 part1
1. Allow to disable gisa
 2. protected virtual machines
   Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's
   state like guest memory and guest registers anymore. Instead the
   PVMs are mostly managed by a new entity called Ultravisor (UV),
   which provides an API, so KVM and the PV can request management
   actions.
 
   PVMs are encrypted at rest and protected from hypervisor access
   while running.  They switch from a normal operation into protected
   mode, so we can still use the standard boot process to load a
   encrypted blob and then move it into protected mode.
 
   Rebooting is only possible by passing through the unprotected/normal
   mode and switching to protected again.
 
   One mm related patch will go via Andrews mm tree ( mm/gup/writeback:
   add callbacks for inaccessible pages)
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Merge tag 'kvm-s390-next-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Features and Enhancements for 5.7 part1

1. Allow to disable gisa
2. protected virtual machines
  Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's
  state like guest memory and guest registers anymore. Instead the
  PVMs are mostly managed by a new entity called Ultravisor (UV),
  which provides an API, so KVM and the PV can request management
  actions.

  PVMs are encrypted at rest and protected from hypervisor access
  while running.  They switch from a normal operation into protected
  mode, so we can still use the standard boot process to load a
  encrypted blob and then move it into protected mode.

  Rebooting is only possible by passing through the unprotected/normal
  mode and switching to protected again.

  One mm related patch will go via Andrews mm tree ( mm/gup/writeback:
  add callbacks for inaccessible pages)
2020-03-16 18:19:34 +01:00
Vitaly Kuznetsov 6d05a965ad KVM: selftests: enlightened VMPTRLD with an incorrect GPA
Check that guest doesn't hang when an invalid eVMCS GPA is specified.
Testing that #UD is injected would probably be better but selftests lack
the infrastructure currently.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 18:19:32 +01:00
Vitaly Kuznetsov 41b0552aa6 KVM: selftests: test enlightened vmenter with wrong eVMCS version
Check that VMfailInvalid happens when eVMCS revision is is invalid.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 18:19:32 +01:00
Vitaly Kuznetsov 7bcf732e74 KVM: selftests: define and use EVMCS_VERSION
KVM allows to use revision_id from MSR_IA32_VMX_BASIC as eVMCS revision_id
to workaround a bug in genuine Hyper-V (see the comment in
nested_vmx_handle_enlightened_vmptrld()), this shouldn't be used by
default. Switch to using KVM_EVMCS_VERSION(1).

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 18:19:31 +01:00
Vitaly Kuznetsov b6a0653ae2 KVM: nVMX: properly handle errors in nested_vmx_handle_enlightened_vmptrld()
nested_vmx_handle_enlightened_vmptrld() fails in two cases:
- when we fail to kvm_vcpu_map() the supplied GPA
- when revision_id is incorrect.
Genuine Hyper-V raises #UD in the former case (at least with *some*
incorrect GPAs) and does VMfailInvalid() in the later. KVM doesn't do
anything so L1 just gets stuck retrying the same faulty VMLAUNCH.

nested_vmx_handle_enlightened_vmptrld() has two call sites:
nested_vmx_run() and nested_get_vmcs12_pages(). The former needs to queue
do much: the failure there happens after migration when L2 was running (and
L1 did something weird like wrote to VP assist page from a different vCPU),
just kill L1 with KVM_EXIT_INTERNAL_ERROR.

Reported-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
[Squash kbuild autopatch. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 18:19:30 +01:00
Vitaly Kuznetsov e942dbf8c5 KVM: nVMX: stop abusing need_vmcs12_to_shadow_sync for eVMCS mapping
When vmx_set_nested_state() happens, we may not have all the required
data to map enlightened VMCS: e.g. HV_X64_MSR_VP_ASSIST_PAGE MSR may not
yet be restored so we need a postponed action. Currently, we (ab)use
need_vmcs12_to_shadow_sync/nested_sync_vmcs12_to_shadow() for that but
this is not ideal:
- We may not need to sync anything if L2 is running
- It is hard to propagate errors from nested_sync_vmcs12_to_shadow()
 as we call it from vmx_prepare_switch_to_guest() which happens just
 before we do VMLAUNCH, the code is not ready to handle errors there.

Move eVMCS mapping to nested_get_vmcs12_pages() and request
KVM_REQ_GET_VMCS12_PAGES, it seems to be is less abusive in nature.
It would probably be possible to introduce a specialized KVM_REQ_EVMCS_MAP
but it is undesirable to propagate eVMCS specifics all the way up to x86.c

Note, we don't need to request KVM_REQ_GET_VMCS12_PAGES from
vmx_set_nested_state() directly as nested_vmx_enter_non_root_mode() already
does that. Requesting KVM_REQ_GET_VMCS12_PAGES is done to document the
(non-obvious) side-effect and to be future proof.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 18:19:29 +01:00
Paolo Bonzini 0c546725ee Merge branch 'kvm-null-pointer-fix' into HEAD 2020-03-16 17:59:11 +01:00
Wainer dos Santos Moschetta 352be2c539 selftests: kvm: Uses TEST_FAIL in tests/utilities
Changed all tests and utilities to use TEST_FAIL macro
instead of TEST_ASSERT(false,...).

Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:11 +01:00
Wainer dos Santos Moschetta a46f8a63cd selftests: kvm: Introduce the TEST_FAIL macro
Some tests/utilities use the TEST_ASSERT(false, ...) pattern to
indicate a failure and stop execution.

This change introduces the TEST_FAIL macro which is a wrap around
TEST_ASSERT(false, ...) and so provides a direct alternative for
failing a test.

Signed-off-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:10 +01:00
Christian Borntraeger 3203a01737 selftests: KVM: s390: check for registers to NOT change on reset
Normal reset and initial CPU reset do not clear all registers. Add a
test that those registers are NOT changed.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:09 +01:00
Christian Borntraeger b0435a12a6 selftests: KVM: s390: test more register variants for the reset ioctl
We should not only test the oneregs or the get_(x)regs interfaces but
also the sync_regs. Those are usually the canonical place for register
content.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:08 +01:00
Christian Borntraeger 41cbed5b07 selftests: KVM: s390: fix early guest crash
The guest crashes very early due to changes in the control registers
used by dynamic address translation. Let us use different registers
that will not crash the guest.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:07 +01:00
Andrew Jones 94c4b76b88 KVM: selftests: Introduce steal-time test
The steal-time test confirms what is reported to the guest as stolen
time is consistent with the run_delay reported for the VCPU thread
on the host. Both x86_64 and AArch64 have the concept of steal/stolen
time so this test is introduced for both architectures.

While adding the test we ensure .gitignore has all tests listed
(it was missing s390x/resets) and that the Makefile has all tests
listed in alphabetical order (not really necessary, but it almost
was already...). We also extend the common API with a new num-guest-
pages call and a new timespec call.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:07 +01:00
Andrew Jones beca54702d KVM: selftests: virt_map should take npages, not size
Also correct the comment and prototype for vm_create_default(),
as it takes a number of pages, not a size.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:06 +01:00
Andrew Jones d0aac3320d KVM: selftests: Use consistent message for test skipping
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:05 +01:00
Andrew Jones d9eaf19ecc KVM: selftests: Enable printf format warnings for TEST_ASSERT
Use the format attribute to enable printf format warnings, and
then fix them all.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:04 +01:00
Christian Borntraeger 6a46fcf92f selftests: KVM: s390: fix format strings for access reg test
acrs are 32 bit and not 64 bit.

Reported-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:03 +01:00
Christian Borntraeger 53362fe930 selftests: KVM: s390: fixup fprintf format error in reset.c
value is u64 and not string.

Reported-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:03 +01:00
Andrew Jones 425936246f KVM: selftests: Share common API documentation
Move function documentation comment blocks to the header files in
order to avoid duplicating them for each architecture. While at
it clean up and fix up the comment blocks.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:02 +01:00
Andrew Jones 1914f624f5 selftests: KVM: SVM: Add vmcall test to gitignore
Add svm_vmcall_test to gitignore list, and realphabetize it.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:01 +01:00
Miaohe Lin 0b66465344 KVM: nSVM: Remove an obsolete comment.
The function does not return bool anymore.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:59:00 +01:00
Paolo Bonzini 8e205a6b2a KVM: X86: correct meaningless kvm_apicv_activated() check
After test_and_set_bit() for kvm->arch.apicv_inhibit_reasons, we will
always get false when calling kvm_apicv_activated() because it's sure
apicv_inhibit_reasons do not equal to 0.

What the code wants to do, is check whether APICv was *already* active
and if so skip the costly request; we can do this using cmpxchg.

Reported-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:59 +01:00
Oliver Upton 212617dbb6 KVM: nVMX: Consolidate nested MTF checks to helper function
commit 5ef8acbdd6 ("KVM: nVMX: Emulate MTF when performing
instruction emulation") introduced a helper to check the MTF
VM-execution control in vmcs12. Change pre-existing check in
nested_vmx_exit_reflected() to instead use the helper.

Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:59 +01:00
Wanpeng Li 041bc42ce2 KVM: VMX: Micro-optimize vmexit time when not exposing PMU
PMU is not exposed to guest by most of products from cloud providers since the
bad performance of PMU emulation and security concern. However, it calls
perf_guest_switch_get_msrs() and clear_atomic_switch_msr() unconditionally
even if PMU is not exposed to the guest before each vmentry.

~2% vmexit time reduced can be observed by kvm-unit-tests/vmexit.flat on my
SKX server.

Before patch:
vmcall 1559

After patch:
vmcall 1529

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:58 +01:00
Andrew Jones 331b4de9a7 KVM: selftests: s390x: Provide additional num-guest-pages adjustment
s390 requires 1M aligned guest sizes. Embedding the rounding in
vm_adjust_num_guest_pages() allows us to remove it from a few
other places.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:57 +01:00
Suravee Suthikulpanit ab56f8e62d kvm: svm: Introduce GA Log tracepoint for AVIC
GA Log tracepoint is useful when debugging AVIC performance
issue as it can be used with perf to count the number of times
IOMMU AVIC injects interrupts through the slow-path instead of
directly inject interrupts to the target vcpu.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:56 +01:00
Peter Xu 3ac40c404c KVM: Documentation: Update fast page fault for indirect sp
Clarify locking.rst to mention early that we're not enabling fast page
fault for indirect sps.  The previous wording is confusing, in that it
seems the proposed solution has been already implemented but it has not.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:56 +01:00
Paolo Bonzini 78f2145c4d KVM: nSVM: avoid loss of pending IRQ/NMI before entering L2
This patch reproduces for nSVM the change that was made for nVMX in
commit b5861e5cf2 ("KVM: nVMX: Fix loss of pending IRQ/NMI before
entering L2").  While I do not have a test that breaks without it, I
cannot see why it would not be necessary since all events are unblocked
by VMRUN's setting of GIF back to 1.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:55 +01:00
Paolo Bonzini b518ba9fa6 KVM: nSVM: implement check_nested_events for interrupts
The current implementation of physical interrupt delivery to a nested guest
is quite broken.  It relies on svm_interrupt_allowed returning false if
VINTR=1 so that the interrupt can be injected from enable_irq_window,
but this does not work for guests that do not intercept HLT or that rely
on clearing the host IF to block physical interrupts while L2 runs.

This patch can be split in two logical parts, but including only
one breaks tests so I am combining both changes together.

The first and easiest is simply to return true for svm_interrupt_allowed
if HF_VINTR_MASK is set and HIF is set.  This way the semantics of
svm_interrupt_allowed are respected: svm_interrupt_allowed being false
does not mean "call enable_irq_window", it means "interrupts cannot
be injected now".

After doing this, however, we need another place to inject the
interrupt, and fortunately we already have one, check_nested_events,
which nested SVM does not implement but which is meant exactly for this
purpose.  It is called before interrupts are injected, and it can
therefore do the L2->L1 switch while leaving inject_pending_event
none the wiser.

This patch was developed together with Cathy Avery, who wrote the
test and did a lot of the initial debugging.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:54 +01:00
Paolo Bonzini 64b5bd2704 KVM: nSVM: ignore L1 interrupt window while running L2 with V_INTR_MASKING=1
If a nested VM is started while an IRQ was pending and with
V_INTR_MASKING=1, the behavior of the guest depends on host IF.  If it
is 1, the VM should exit immediately, before executing the first
instruction of the guest, because VMRUN sets GIF back to 1.

If it is 0 and the host has VGIF, however, at the time of the VMRUN
instruction L0 is running the guest with a pending interrupt window
request.  This interrupt window request is completely irrelevant to
L2, since IF only controls virtual interrupts, so this patch drops
INTERCEPT_VINTR from the VMCB while running L2 under these circumstances.
To simplify the code, both steps of enabling the interrupt window
(setting the VINTR intercept and requesting a fake virtual interrupt
in svm_inject_irq) are grouped in the svm_set_vintr function, and
likewise for dismissing the interrupt window request in svm_clear_vintr.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:53 +01:00
Paolo Bonzini b5ec2e020b KVM: nSVM: do not change host intercepts while nested VM is running
Instead of touching the host intercepts so that the bitwise OR in
recalc_intercepts just works, mask away uninteresting intercepts
directly in recalc_intercepts.

This is cleaner and keeps the logic in one place even for intercepts
that can change even while L2 is running.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:53 +01:00
Paolo Bonzini 727a7e27cf KVM: x86: rename set_cr3 callback and related flags to load_mmu_pgd
The set_cr3 callback is not setting the guest CR3, it is setting the
root of the guest page tables, either shadow or two-dimensional.
To make this clearer as well as to indicate that the MMU calls it
via kvm_mmu_load_cr3, rename it to load_mmu_pgd.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:52 +01:00
Paolo Bonzini 689f3bf216 KVM: x86: unify callbacks to load paging root
Similar to what kvm-intel.ko is doing, provide a single callback that
merges svm_set_cr3, set_tdp_cr3 and nested_svm_set_tdp_cr3.

This lets us unify the set_cr3 and set_tdp_cr3 entries in kvm_x86_ops.
I'm doing that in this same patch because splitting it adds quite a bit
of churn due to the need for forward declarations.  For the same reason
the assignment to vcpu->arch.mmu->set_cr3 is moved to kvm_init_shadow_mmu
from init_kvm_softmmu and nested_svm_init_mmu_context.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:51 +01:00
Sean Christopherson f91af5176c KVM: x86: Refactor kvm_cpuid() param that controls out-of-range logic
Invert and rename the kvm_cpuid() param that controls out-of-range logic
to better reflect the semantics of the affected callers, i.e. callers
that bypass the out-of-range logic do so because they are looking up an
exact guest CPUID entry, e.g. to query the maxphyaddr.

Similarly, rename kvm_cpuid()'s internal "found" to "exact" to clarify
that it tracks whether or not the exact requested leaf was found, as
opposed to any usable leaf being found.

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:50 +01:00
Sean Christopherson 09c7431ed3 KVM: x86: Refactor out-of-range logic to contain the madness
Move all of the out-of-range logic into a single helper,
get_out_of_range_cpuid_entry(), to avoid an extra lookup of CPUID.0.0
and to provide a single location for documenting the out-of-range
behavior.

No functional change intended.

Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:49 +01:00
Sean Christopherson 8d8923115f KVM: x86: Fix CPUID range checks for Hypervisor and Centaur classes
Rework the masking in the out-of-range CPUID logic to handle the
Hypervisor sub-classes, as well as the Centaur class if the guest
virtual CPU vendor is Centaur.

Masking against 0x80000000 only handles basic and extended leafs, which
results in Hypervisor range checks being performed against the basic
CPUID class, and Centuar range checks being performed against the
Extended class.  E.g. if CPUID.0x40000000.EAX returns 0x4000000A and
there is no entry for CPUID.0x40000006, then function 0x40000006 would
be incorrectly reported as out of bounds.

While there is no official definition of what constitutes a class, the
convention established for Hypervisor classes effectively uses bits 31:8
as the mask by virtue of checking for different bases in increments of
0x100, e.g. KVM advertises its CPUID functions starting at 0x40000100
when HyperV features are advertised at the default base of 0x40000000.

The bad range check doesn't cause functional problems for any known VMM
because out-of-range semantics only come into play if the exact entry
isn't found, and VMMs either support a very limited Hypervisor range,
e.g. the official KVM range is 0x40000000-0x40000001 (effectively no
room for undefined leafs) or explicitly defines gaps to be zero, e.g.
Qemu explicitly creates zeroed entries up to the Centaur and Hypervisor
limits (the latter comes into play when providing HyperV features).

The bad behavior can be visually confirmed by dumping CPUID output in
the guest when running Qemu with a stable TSC, as Qemu extends the limit
of range 0x40000000 to 0x40000010 to advertise VMware's cpuid_freq,
without defining zeroed entries for 0x40000002 - 0x4000000f.

Note, documentation of Centaur/VIA CPUs is hard to come by.  Designating
0xc0000000 - 0xcfffffff as the Centaur class is a best guess as to the
behavior of a real Centaur/VIA CPU.

Fixes: 43561123ab ("kvm: x86: Improve emulation of CPUID leaves 0BH and 1FH")
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:49 +01:00
Sean Christopherson 23493d0a17 KVM x86: Extend AMD specific guest behavior to Hygon virtual CPUs
Extend guest_cpuid_is_amd() to cover Hygon virtual CPUs and rename it
accordingly.  Hygon CPUs use an AMD-based core and so have the same
basic behavior as AMD CPUs.

Fixes: b8f4abb652 ("x86/kvm: Add Hygon Dhyana support to KVM")
Cc: Pu Wen <puwen@hygon.cn>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:48 +01:00
Sean Christopherson 15608ed03f KVM: x86: Add helpers to perform CPUID-based guest vendor check
Add helpers to provide CPUID-based guest vendor checks, i.e. to do the
ugly register comparisons.  Use the new helpers to check for an AMD
guest vendor in guest_cpuid_is_amd() as well as in the existing emulator
flows.

Using the new helpers fixes a _very_ theoretical bug where
guest_cpuid_is_amd() would get a false positive on a non-AMD virtual CPU
with a vendor string beginning with "Auth" due to the previous logic
only checking EBX.  It also fixes a marginally less theoretically bug
where guest_cpuid_is_amd() would incorrectly return false for a guest
CPU with "AMDisbetter!" as its vendor string.

Fixes: a0c0feb579 ("KVM: x86: reserve bit 8 of non-leaf PDPEs and PML4Es in 64-bit mode on AMD")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:47 +01:00
Jan Kiszka b7fb8488c8 KVM: x86: Trace the original requested CPUID function in kvm_cpuid()
Trace the requested CPUID function instead of the effective function,
e.g. if the requested function is out-of-range and KVM is emulating an
Intel CPU, as the intent of the tracepoint is to show if the output came
from the actual leaf as opposed to the max basic leaf via redirection.

Similarly, leave "found" as is, i.e. report that an entry was found if
and only if the requested entry was found.

Fixes: 43561123ab ("kvm: x86: Improve emulation of CPUID leaves 0BH and 1FH")
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
[Sean: Drop "found" semantic change, reword changelong accordingly ]
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:46 +01:00
Paolo Bonzini 408e9a318f KVM: CPUID: add support for supervisor states
Current CPUID 0xd enumeration code does not support supervisor
states, because KVM only supports setting IA32_XSS to zero.
Change it instead to use a new variable supported_xss, to be
set from the hardware_setup callback which is in charge of CPU
capabilities.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:45 +01:00
Sean Christopherson 257038745c KVM: x86: Move nSVM CPUID 0x8000000A handling into common x86 code
Handle CPUID 0x8000000A in the main switch in __do_cpuid_func() and drop
->set_supported_cpuid() now that both VMX and SVM implementations are
empty.  Like leaf 0x14 (Intel PT) and leaf 0x8000001F (SEV), leaf
0x8000000A is is (obviously) vendor specific but can be queried in
common code while respecting SVM's wishes by querying kvm_cpu_cap_has().

Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:45 +01:00
Sean Christopherson 4eb87460c4 KVM: nSVM: Advertise and enable NRIPS for L1 iff nrips is enabled
Set NRIPS in KVM capabilities if and only if nrips=true, which naturally
incorporates the boot_cpu_has() check, and set nrips_enabled only if the
KVM capability is enabled.

Note, previously KVM would set nrips_enabled based purely on userspace
input, but at worst that would cause KVM to propagate garbage into L1,
i.e. userspace would simply be hosing its VM.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:44 +01:00
Sean Christopherson a50718cc3f KVM: nSVM: Expose SVM features to L1 iff nested is enabled
Set SVM feature bits in KVM capabilities if and only if nested=true, KVM
shouldn't advertise features that realistically can't be used.  Use
kvm_cpu_cap_has(X86_FEATURE_SVM) to indirectly query "nested" in
svm_set_supported_cpuid() in anticipation of moving CPUID 0x8000000A
adjustments into common x86 code.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:43 +01:00
Sean Christopherson 91661989d1 KVM: x86: Move VMX's host_efer to common x86 code
Move host_efer to common x86 code and use it for CPUID's is_efer_nx() to
avoid constantly re-reading the MSR.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:42 +01:00
Sean Christopherson 600087b614 KVM: Drop largepages_enabled and its accessor/mutator
Drop largepages_enabled, kvm_largepages_enabled() and
kvm_disable_largepages() now that all users are gone.

Note, largepages_enabled was an x86-only flag that got left in common
KVM code when KVM gained support for multiple architectures.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:42 +01:00
Sean Christopherson e884b854ee KVM: x86: Don't propagate MMU lpage support to memslot.disallow_lpage
Stop propagating MMU large page support into a memslot's disallow_lpage
now that the MMU's max_page_level handles the scenario where VMX's EPT is
enabled and EPT doesn't support 2M pages.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:41 +01:00
Sean Christopherson 703c335d06 KVM: x86/mmu: Configure max page level during hardware setup
Configure the max page level during hardware setup to avoid a retpoline
in the page fault handler.  Drop ->get_lpage_level() as the page fault
handler was the last user.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:40 +01:00
Sean Christopherson bde7723559 KVM: x86/mmu: Merge kvm_{enable,disable}_tdp() into a common function
Combine kvm_enable_tdp() and kvm_disable_tdp() into a single function,
kvm_configure_mmu(), in preparation for doing additional configuration
during hardware setup.  And because having separate helpers is silly.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:58:39 +01:00