Commit Graph

164 Commits

Author SHA1 Message Date
Paolo Bonzini
b376144595 Merge tag 'kvm-x86-fixes-6.2-1' of https://github.com/kvm-x86/linux into HEAD
Misc KVM x86 fixes and cleanups for 6.2:

 - One-off fixes for various emulation flows (SGX, VMXON, NRIPS=0).

 - Reinstate IBPB on emulated VM-Exit that was incorrectly dropped a few
   years back when eliminating unnecessary barriers when switching between
   vmcs01 and vmcs02.

 - Clean up the MSR filter docs.

 - Clean up vmread_error_trampoline() to make it more obvious that params
   must be passed on the stack, even for x86-64.

 - Let userspace set all supported bits in MSR_IA32_FEAT_CTL irrespective
   of the current guest CPUID.

 - Fudge around a race with TSC refinement that results in KVM incorrectly
   thinking a guest needs TSC scaling when running on a CPU with a
   constant TSC, but no hardware-enumerated TSC frequency.
2022-12-02 12:56:25 -05:00
Sean Christopherson
0c3265235f KVM: selftests: Define and use a custom static assert in lib headers
Define and use kvm_static_assert() in the common KVM selftests headers to
provide deterministic behavior, and to allow creating static asserts
without dummy messages.

The kernel's static_assert() makes the message param optional, and on the
surface, tools/include/linux/build_bug.h appears to follow suit.  However,
glibc may override static_assert() and redefine it as a direct alias of
_Static_assert(), which makes the message parameter mandatory.  This leads
to non-deterministic behavior as KVM selftests code that utilizes
static_assert() without a custom message may or not compile depending on
the order of includes.  E.g. recently added asserts in
x86_64/processor.h fail on some systems with errors like

  In file included from lib/memstress.c:11:0:
  include/x86_64/processor.h: In function ‘this_cpu_has_p’:
  include/x86_64/processor.h:193:34: error: expected ‘,’ before ‘)’ token
    static_assert(low_bit < high_bit);     \
                                    ^
due to _Static_assert() expecting a comma before a message.  The "message
optional" version of static_assert() uses macro magic to strip away the
comma when presented with empty an __VA_ARGS__

  #ifndef static_assert
  #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
  #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
  #endif // static_assert

and effectively generates "_Static_assert(expr, #expr)".

The incompatible version of static_assert() gets defined by this snippet
in /usr/include/assert.h:

  #if defined __USE_ISOC11 && !defined __cplusplus
  # undef static_assert
  # define static_assert _Static_assert
  #endif

which yields "_Static_assert(expr)" and thus fails as above.

KVM selftests don't actually care about using C11, but __USE_ISOC11 gets
defined because of _GNU_SOURCE, which many tests do #define.  _GNU_SOURCE
triggers a massive pile of defines in /usr/include/features.h, including
_ISOC11_SOURCE:

  /* If _GNU_SOURCE was defined by the user, turn on all the other features.  */
  #ifdef _GNU_SOURCE
  # undef  _ISOC95_SOURCE
  # define _ISOC95_SOURCE 1
  # undef  _ISOC99_SOURCE
  # define _ISOC99_SOURCE 1
  # undef  _ISOC11_SOURCE
  # define _ISOC11_SOURCE 1
  # undef  _POSIX_SOURCE
  # define _POSIX_SOURCE  1
  # undef  _POSIX_C_SOURCE
  # define _POSIX_C_SOURCE        200809L
  # undef  _XOPEN_SOURCE
  # define _XOPEN_SOURCE  700
  # undef  _XOPEN_SOURCE_EXTENDED
  # define _XOPEN_SOURCE_EXTENDED 1
  # undef  _LARGEFILE64_SOURCE
  # define _LARGEFILE64_SOURCE    1
  # undef  _DEFAULT_SOURCE
  # define _DEFAULT_SOURCE        1
  # undef  _ATFILE_SOURCE
  # define _ATFILE_SOURCE 1
  #endif

which further down in /usr/include/features.h leads to:

  /* This is to enable the ISO C11 extension.  */
  #if (defined _ISOC11_SOURCE \
       || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L))
  # define __USE_ISOC11   1
  #endif

To make matters worse, /usr/include/assert.h doesn't guard against
multiple inclusion by turning itself into a nop, but instead #undefs a
few macros and continues on.  As a result, it's all but impossible to
ensure the "message optional" version of static_assert() will actually be
used, e.g. explicitly including assert.h and #undef'ing static_assert()
doesn't work as a later inclusion of assert.h will again redefine its
version.

  #ifdef  _ASSERT_H

  # undef _ASSERT_H
  # undef assert
  # undef __ASSERT_VOID_CAST

  # ifdef __USE_GNU
  #  undef assert_perror
  # endif

  #endif /* assert.h      */

  #define _ASSERT_H       1
  #include <features.h>

Fixes: fcba483e82 ("KVM: selftests: Sanity check input to ioctls() at build time")
Fixes: ee37955366 ("KVM: selftests: Refactor X86_FEATURE_* framework to prep for X86_PROPERTY_*")
Fixes: 53a7dc0f21 ("KVM: selftests: Add X86_PROPERTY_* framework to retrieve CPUID values")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221122013309.1872347-1-seanjc@google.com
2022-12-01 15:31:46 -08:00
Sean Christopherson
8fcee04213 KVM: selftests: Restore assert for non-nested VMs in access tracking test
Restore the assert (on x86-64) that <10% of pages are still idle when NOT
running as a nested VM in the access tracking test.  The original assert
was converted to a "warning" to avoid false failures when running the
test in a VM, but the non-nested case does not suffer from the same
"infinite TLB size" issue.

Using the HYPERVISOR flag isn't infallible as VMMs aren't strictly
required to enumerate the "feature" in CPUID, but practically speaking
anyone that is running KVM selftests in VMs is going to be using a VMM
and hypervisor that sets the HYPERVISOR flag.

Cc: David Matlack <dmatlack@google.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221129175300.4052283-3-seanjc@google.com
2022-12-01 15:31:39 -08:00
Sean Christopherson
b80732fdc9 KVM: selftests: Verify userspace can stuff IA32_FEATURE_CONTROL at will
Verify the KVM allows userspace to set all supported bits in the
IA32_FEATURE_CONTROL MSR irrespective of the current guest CPUID, and
that all unsupported bits are rejected.

Throw the testcase into vmx_msrs_test even though it's not technically a
VMX MSR; it's close enough, and the most frequently feature controlled by
the MSR is VMX.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220607232353.3375324-4-seanjc@google.com
2022-11-30 16:29:54 -08:00
Vitaly Kuznetsov
9c2e881945 KVM: selftests: hyperv_svm_test: Introduce L2 TLB flush test
Enable Hyper-V L2 TLB flush and check that Hyper-V TLB flush hypercalls
from L2 don't exit to L1 unless 'TlbLockCount' is set in the Partition
assist page.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-48-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:42:43 -05:00
Vitaly Kuznetsov
4b5d8b222b KVM: selftests: evmcs_test: Introduce L2 TLB flush test
Enable Hyper-V L2 TLB flush and check that Hyper-V TLB flush hypercalls
from L2 don't exit to L1 unless 'TlbLockCount' is set in the
Partition assist page.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-47-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:42:41 -05:00
Vitaly Kuznetsov
8fda37cf3d KVM: selftests: Stuff RAX/RCX with 'safe' values in vmmcall()/vmcall()
vmmcall()/vmcall() are used to exit from L2 to L1 and no concrete hypercall
ABI is currenty followed. With the introduction of Hyper-V L2 TLB flush
it becomes (theoretically) possible that L0 will take responsibility for
handling the call and no L1 exit will happen. Prevent this by stuffing RAX
(KVM ABI) and RCX (Hyper-V ABI) with 'safe' values.

While on it, convert vmmcall() to 'static inline', make it setup stack
frame and move to include/x86_64/svm_util.h.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-45-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:42:38 -05:00
Vitaly Kuznetsov
6c15c3c465 KVM: selftests: Allocate Hyper-V partition assist page
In preparation to testing Hyper-V L2 TLB flush hypercalls, allocate
so-called Partition assist page.

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-44-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:41:59 -05:00
Vitaly Kuznetsov
2dc458b862 KVM: selftests: Create a vendor independent helper to allocate Hyper-V specific test pages
There's no need to pollute VMX and SVM code with Hyper-V specific
stuff and allocate Hyper-V specific test pages for all test as only
few really need them. Create a dedicated struct and an allocation
helper.

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-43-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:41:22 -05:00
Vitaly Kuznetsov
cd8f11bd6b KVM: selftests: Split off load_evmcs() from load_vmcs()
In preparation to putting Hyper-V specific test pages to a dedicated
struct, move eVMCS load logic from load_vmcs(). Tests call load_vmcs()
directly and the only one which needs 'enlightened' version is
evmcs_test so there's not much gain in having this merged.

Temporary pass both GPA and HVA to load_evmcs().

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-42-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:40:42 -05:00
Vitaly Kuznetsov
e8f3d23c02 KVM: selftests: Move Hyper-V VP assist page enablement out of evmcs.h
Hyper-V VP assist page is not eVMCS specific, it is also used for
enlightened nSVM. Move the code to vendor neutral place.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-41-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:40:05 -05:00
Vitaly Kuznetsov
d7b14a868a KVM: selftests: Sync 'struct hv_vp_assist_page' definition with hyperv-tlfs.h
'struct hv_vp_assist_page' definition doesn't match TLFS. Also, define
'struct hv_nested_enlightenments_control' and use it instead of opaque
'__u64'.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-40-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:40:04 -05:00
Vitaly Kuznetsov
1ad51c0c0c KVM: selftests: Sync 'struct hv_enlightened_vmcs' definition with hyperv-tlfs.h
'struct hv_enlightened_vmcs' definition in selftests is not '__packed'
and so we rely on the compiler doing the right padding. This is not
obvious so it seems beneficial to use the same definition as in kernel.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-39-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:40:03 -05:00
Vitaly Kuznetsov
9e7726a8a0 KVM: selftests: Hyper-V PV TLB flush selftest
Introduce a selftest for Hyper-V PV TLB flush hypercalls
(HvFlushVirtualAddressSpace/HvFlushVirtualAddressSpaceEx,
HvFlushVirtualAddressList/HvFlushVirtualAddressListEx).

The test creates one 'sender' vCPU and two 'worker' vCPU which do busy
loop reading from a certain GVA checking the observed value. Sender
vCPU swaos the data page with another page filled with a different value.
The expectation for workers is also altered. Without TLB flush on worker
vCPUs, they may continue to observe old value. To guard against accidental
TLB flushes for worker vCPUs the test is repeated 100 times.

Hyper-V TLB flush hypercalls are tested in both 'normal' and 'XMM
fast' modes.

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-38-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-21 06:40:01 -05:00
Vitaly Kuznetsov
998489245d KVM: selftests: Hyper-V PV IPI selftest
Introduce a selftest for Hyper-V PV IPI hypercalls
(HvCallSendSyntheticClusterIpi, HvCallSendSyntheticClusterIpiEx).

The test creates one 'sender' vCPU and two 'receiver' vCPU and then
issues various combinations of send IPI hypercalls in both 'normal'
and 'fast' (with XMM input where necessary) mode. Later, the test
checks whether IPIs were delivered to the expected destination vCPU[s].

Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-34-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18 13:07:58 -05:00
Vitaly Kuznetsov
caf4110fba KVM: selftests: Move the function doing Hyper-V hypercall to a common header
All Hyper-V specific tests issuing hypercalls need this.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-33-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18 13:05:17 -05:00
Vitaly Kuznetsov
c05a0a71c5 KVM: selftests: Move HYPERV_LINUX_OS_ID definition to a common header
HYPERV_LINUX_OS_ID needs to be written to HV_X64_MSR_GUEST_OS_ID by
each Hyper-V specific selftest.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-32-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18 12:59:21 -05:00
Vitaly Kuznetsov
676a863ce6 KVM: selftests: Better XMM read/write helpers
set_xmm()/get_xmm() helpers are fairly useless as they only read 64 bits
from 128-bit registers. Moreover, these helpers are not used. Borrow
_kvm_read_sse_reg()/_kvm_write_sse_reg() from KVM limiting them to
XMM0-XMM8 for now.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-31-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18 12:59:20 -05:00
Sean Christopherson
26b516bb39 x86/hyperv: KVM: Rename "hv_enlightenments" to "hv_vmcb_enlightenments"
Now that KVM isn't littered with "struct hv_enlightenments" casts, rename
the struct to "hv_vmcb_enlightenments" to highlight the fact that the
struct is specifically for SVM's VMCB.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-5-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18 12:58:59 -05:00
Sean Christopherson
68ae7c7bc5 KVM: SVM: Add a proper field for Hyper-V VMCB enlightenments
Add a union to provide hv_enlightenments side-by-side with the sw_reserved
bytes that Hyper-V's enlightenments overlay.  Casting sw_reserved
everywhere is messy, confusing, and unnecessarily unsafe.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-4-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18 12:58:58 -05:00
Sean Christopherson
381fc63ac0 KVM: selftests: Move "struct hv_enlightenments" to x86_64/svm.h
Move Hyper-V's VMCB "struct hv_enlightenments" to the svm.h header so
that the struct can be referenced in "struct vmcb_control_area".
Alternatively, a dedicated header for SVM+Hyper-V could be added, a la
x86_64/evmcs.h, but it doesn't appear that Hyper-V will end up needing
a wholesale replacement for the VMCB.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-18 12:58:58 -05:00
Paolo Bonzini
771a579c6e Merge branch 'kvm-svm-harden' into HEAD
This fixes three issues in nested SVM:

1) in the shutdown_interception() vmexit handler we call kvm_vcpu_reset().
However, if running nested and L1 doesn't intercept shutdown, the function
resets vcpu->arch.hflags without properly leaving the nested state.
This leaves the vCPU in inconsistent state and later triggers a kernel
panic in SVM code.  The same bug can likely be triggered by sending INIT
via local apic to a vCPU which runs a nested guest.

On VMX we are lucky that the issue can't happen because VMX always
intercepts triple faults, thus triple fault in L2 will always be
redirected to L1.  Plus, handle_triple_fault() doesn't reset the vCPU.
INIT IPI can't happen on VMX either because INIT events are masked while
in VMX mode.

Secondarily, KVM doesn't honour SHUTDOWN intercept bit of L1 on SVM.
A normal hypervisor should always intercept SHUTDOWN, a unit test on
the other hand might want to not do so.

Finally, the guest can trigger a kernel non rate limited printk on SVM
from the guest, which is fixed as well.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-17 11:51:09 -05:00
Maxim Levitsky
fc6392d51d KVM: selftests: move idt_entry to header
struct idt_entry will be used for a test which will break IDT on purpose.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20221103141351.50662-6-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-17 11:39:58 -05:00
David Matlack
ecb89a5172 KVM: selftests: Check for KVM nEPT support using "feature" MSRs
When checking for nEPT support in KVM, use kvm_get_feature_msr() instead
of vcpu_get_msr() to retrieve KVM's default TRUE_PROCBASED_CTLS and
PROCBASED_CTLS2 MSR values, i.e. don't require a VM+vCPU to query nEPT
support.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20220927165209.930904-1-dmatlack@google.com
[sean: rebase on merged code, write changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-11-16 16:59:07 -08:00
Sean Christopherson
b941ba2380 KVM: selftests: Drop helpers for getting specific KVM supported CPUID entry
Drop kvm_get_supported_cpuid_entry() and its inner helper now that all
known usage can use X86_FEATURE_*, X86_PROPERTY_*, X86_PMU_FEATURE_*, or
the dedicated Family/Model helpers.  Providing "raw" access to CPUID
leafs is undesirable as it encourages open coding CPUID checks, which is
often error prone and not self-documenting.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-13-seanjc@google.com
2022-11-16 16:59:07 -08:00
Sean Christopherson
074e9d4c9c KVM: selftests: Add and use KVM helpers for x86 Family and Model
Add KVM variants of the x86 Family and Model helpers, and use them in the
PMU event filter test.  Open code the retrieval of KVM's supported CPUID
entry 0x1.0 in anticipation of dropping kvm_get_supported_cpuid_entry().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-12-seanjc@google.com
2022-11-16 16:59:06 -08:00
Sean Christopherson
24f3f9898e KVM: selftests: Add dedicated helpers for getting x86 Family and Model
Add dedicated helpers for getting x86's Family and Model, which are the
last holdouts that "need" raw access to CPUID information.  FMS info is
a mess and requires not only splicing together multiple values, but
requires doing so conditional in the Family case.

Provide wrappers to reduce the odds of copy+paste errors, but mostly to
allow for the eventual removal of kvm_get_supported_cpuid_entry().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-11-seanjc@google.com
2022-11-16 16:59:06 -08:00
Sean Christopherson
5228c02a4c KVM: selftests: Add PMU feature framework, use in PMU event filter test
Add an X86_PMU_FEATURE_* framework to simplify probing architectural
events on Intel PMUs, which require checking the length of a bit vector
and the _absence_ of a "feature" bit.  Add helpers for both KVM and
"this CPU", and use the newfangled magic (along with X86_PROPERTY_*)
to  clean up pmu_event_filter_test.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-10-seanjc@google.com
2022-11-16 16:59:05 -08:00
Sean Christopherson
4feb9d21a4 KVM: selftests: Convert vmx_pmu_caps_test to use X86_PROPERTY_*
Add X86_PROPERTY_PMU_VERSION and use it in vmx_pmu_caps_test to replace
open coded versions of the same functionality.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-9-seanjc@google.com
2022-11-16 16:59:05 -08:00
Sean Christopherson
5dc19f1c7d KVM: selftests: Convert AMX test to use X86_PROPRETY_XXX
Add and use x86 "properties" for the myriad AMX CPUID values that are
validated by the AMX test.  Drop most of the test's single-usage
helpers so that the asserts more precisely capture what check failed.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-8-seanjc@google.com
2022-11-16 16:59:05 -08:00
Sean Christopherson
40854713e3 KVM: selftests: Add kvm_cpu_*() support for X86_PROPERTY_*
Extent X86_PROPERTY_* support to KVM, i.e. add kvm_cpu_property() and
kvm_cpu_has_p(), and use the new helpers in kvm_get_cpu_address_width().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-7-seanjc@google.com
2022-11-16 16:59:04 -08:00
Sean Christopherson
53a7dc0f21 KVM: selftests: Add X86_PROPERTY_* framework to retrieve CPUID values
Introduce X86_PROPERTY_* to allow retrieving values/properties from CPUID
leafs, e.g. MAXPHYADDR from CPUID.0x80000008.  Use the same core code as
X86_FEATURE_*, the primary difference is that properties are multi-bit
values, whereas features enumerate a single bit.

Add this_cpu_has_p() to allow querying whether or not a property exists
based on the maximum leaf associated with the property, e.g. MAXPHYADDR
doesn't exist if the max leaf for 0x8000_xxxx is less than 0x8000_0008.

Use the new property infrastructure in vm_compute_max_gfn() to prove
that the code works as intended.  Future patches will convert additional
selftests code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-4-seanjc@google.com
2022-11-16 16:59:03 -08:00
Sean Christopherson
ee37955366 KVM: selftests: Refactor X86_FEATURE_* framework to prep for X86_PROPERTY_*
Refactor the X86_FEATURE_* framework to prepare for extending the core
logic to support "properties".  The "feature" framework allows querying a
single CPUID bit to detect the presence of a feature; the "property"
framework will extend the idea to allow querying a value, i.e. to get a
value that is a set of contiguous bits in a CPUID leaf.

Opportunistically add static asserts to ensure features are fully defined
at compile time, and to try and catch mistakes in the definition of
features.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-3-seanjc@google.com
2022-11-16 16:59:03 -08:00
Sean Christopherson
3bd396353d KVM: selftests: Add X86_FEATURE_PAE and use it calc "fallback" MAXPHYADDR
Add X86_FEATURE_PAE and use it to guesstimate the MAXPHYADDR when the
MAXPHYADDR CPUID entry isn't supported.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006005125.680782-2-seanjc@google.com
2022-11-16 16:59:02 -08:00
Sean Christopherson
b9635930f0 KVM: selftests: Provide error code as a KVM_ASM_SAFE() output
Provide the error code on a fault in KVM_ASM_SAFE(), e.g. to allow tests
to assert that #PF generates the correct error code without needing to
manually install a #PF handler.  Use r10 as the scratch register for the
error code, as it's already clobbered by the asm blob (loaded with the
RIP of the to-be-executed instruction).  Deliberately load the output
"error_code" even in the non-faulting path so that error_code is always
initialized with deterministic data (the aforementioned RIP), i.e to
ensure a selftest won't end up with uninitialized consumption regardless
of how KVM_ASM_SAFE() is used.

Don't clear r10 in the non-faulting case and instead load error code with
the RIP (see above).  The error code is valid if and only if an exception
occurs, and '0' isn't necessarily a better "invalid" value, e.g. '0'
could result in false passes for a buggy test.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20221102184654.282799-9-dmatlack@google.com
2022-11-16 16:59:01 -08:00
Sean Christopherson
f2e5b53b4b KVM: selftests: Avoid JMP in non-faulting path of KVM_ASM_SAFE()
Clear R9 in the non-faulting path of KVM_ASM_SAFE() and fall through to
to a common load of "vector" to effectively load "vector" with '0' to
reduce the code footprint of the asm blob, to reduce the runtime overhead
of the non-faulting path (when "vector" is stored in a register), and so
that additional output constraints that are valid if and only if a fault
occur are loaded even in the non-faulting case.

A future patch will add a 64-bit output for the error code, and if its
output is not explicitly loaded with _something_, the user of the asm
blob can end up technically consuming uninitialized data.  Using a
common path to load the output constraints will allow using an existing
scratch register, e.g. r10, to hold the error code in the faulting path,
while also guaranteeing the error code is initialized with deterministic
data in the non-faulting patch (r10 is loaded with the RIP of
to-be-executed instruction).

Consuming the error code when a fault doesn't occur would obviously be a
test bug, but there's no guarantee the compiler will detect uninitialized
consumption.  And conversely, it's theoretically possible that the
compiler might throw a false positive on uninitialized data, e.g. if the
compiler can't determine that the non-faulting path won't touch the error
code.

Alternatively, the error code could be explicitly loaded in the
non-faulting path, but loading a 64-bit memory|register output operand
with an explicitl value requires a sign-extended "MOV imm32, r/m64",
which isn't exactly straightforward and has a largish code footprint.
And loading the error code with what is effectively garbage (from a
scratch register) avoids having to choose an arbitrary value for the
non-faulting case.

Opportunistically remove a rogue asterisk in the block comment.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20221102184654.282799-8-dmatlack@google.com
2022-11-16 16:59:00 -08:00
David Matlack
77f7813cc2 KVM: selftests: Copy KVM PFERR masks into selftests
Copy KVM's macros for page fault error masks into processor.h so they
can be used in selftests.

Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221102184654.282799-7-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2022-11-16 16:59:00 -08:00
Sean Christopherson
96b69958c7 KVM: selftests: Play nice with huge pages when getting PTEs/GPAs
Play nice with huge pages when getting PTEs and translating GVAs to GPAs,
there's no reason to disallow using huge pages in selftests.  Use
PG_LEVEL_NONE to indicate that the caller doesn't care about the mapping
level and just wants to get the pte+level.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006004512.666529-8-seanjc@google.com
2022-11-16 16:58:56 -08:00
Sean Christopherson
91add12d38 KVM: selftests: Remove useless shifts when creating guest page tables
Remove the pointless shift from GPA=>GFN and immediately back to
GFN=>GPA when creating guest page tables.  Ignore the other walkers
that have a similar pattern for the moment, they will be converted
to use virt_get_pte() in the near future.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006004512.666529-4-seanjc@google.com
2022-11-16 16:58:55 -08:00
Sean Christopherson
751f280017 KVM: selftests: Drop reserved bit checks from PTE accessor
Drop the reserved bit checks from the helper to retrieve a PTE, there's
very little value in sanity checking the constructed page tables as any
will quickly be noticed in the form of an unexpected #PF.  The checks
also place unnecessary restrictions on the usage of the helpers, e.g. if
a test _wanted_ to set reserved bits for whatever reason.

Removing the NX check in particular allows for the removal of the @vcpu
param, which will in turn allow the helper to be reused nearly verbatim
for addr_gva2gpa().

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006004512.666529-3-seanjc@google.com
2022-11-16 16:58:54 -08:00
Sean Christopherson
816c54b747 KVM: selftests: Drop helpers to read/write page table entries
Drop vm_{g,s}et_page_table_entry() and instead expose the "inner"
helper (was _vm_get_page_table_entry()) that returns a _pointer_ to the
PTE, i.e. let tests directly modify PTEs instead of bouncing through
helpers that just make life difficult.

Opportunsitically use BIT_ULL() in emulator_error_test, and use the
MAXPHYADDR define to set the "rogue" GPA bit instead of open coding the
same value.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20221006004512.666529-2-seanjc@google.com
2022-11-16 16:58:54 -08:00
Paolo Bonzini
c99ad25b0d Merge tag 'kvm-x86-6.1-2' of https://github.com/sean-jc/linux into HEAD
KVM x86 updates for 6.1, batch #2:

 - Misc PMU fixes and cleanups.

 - Fixes for Hyper-V hypercall selftest
2022-09-30 07:09:48 -04:00
David Matlack
458e98746f KVM: selftests: Fix nx_huge_pages_test on TDP-disabled hosts
Map the test's huge page region with 2MiB virtual mappings when TDP is
disabled so that KVM can shadow the region with huge pages. This fixes
nx_huge_pages_test on hosts where TDP hardware support is disabled.

Purposely do not skip this test on TDP-disabled hosts. While we don't
care about NX Huge Pages on TDP-disabled hosts from a security
perspective, KVM does support it, and so we should test it.

For TDP-enabled hosts, continue mapping the region with 4KiB pages to
ensure that KVM can map it with huge pages irrespective of the guest
mappings.

Fixes: 8448ec5993 ("KVM: selftests: Add NX huge pages test")
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220929181207.2281449-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-30 06:39:36 -04:00
David Matlack
0f816e024f KVM: selftests: Skip tests that require EPT when it is not available
Skip selftests that require EPT support in the VM when it is not
available. For example, if running on a machine where kvm_intel.ept=N
since KVM does not offer EPT support to guests if EPT is not supported
on the host.

This commit causes vmx_dirty_log_test to be skipped instead of failing
on hosts where kvm_intel.ept=N.

Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220926171457.532542-1-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-27 07:58:03 -04:00
Sean Christopherson
1e2e9222e6 KVM: selftests: Use uapi header to get VMX and SVM exit reasons/codes
Include the vmx.h and svm.h uapi headers that KVM so kindly provides
instead of manually defining all the same exit reasons/code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20220830231614.3580124-26-seanjc@google.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-26 12:03:12 -04:00
Vitaly Kuznetsov
8174193163 KVM: selftests: Switch to updated eVMCSv1 definition
Update Enlightened VMCS definition in selftests from KVM.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-14-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-26 12:02:46 -04:00
Vitaly Kuznetsov
a0fa4b7abf KVM: selftests: Add ENCLS_EXITING_BITMAP{,HIGH} VMCS fields
The updated Enlightened VMCS definition has 'encls_exiting_bitmap'
field which needs mapping to VMCS, add the missing encoding.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220830133737.1539624-13-vkuznets@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-09-26 12:02:45 -04:00
David Matlack
372d070845 KVM: selftests: Fix ambiguous mov in KVM_ASM_SAFE()
Change the mov in KVM_ASM_SAFE() that zeroes @vector to a movb to
make it unambiguous.

This fixes a build failure with Clang since, unlike the GNU assembler,
the LLVM integrated assembler rejects ambiguous X86 instructions that
don't have suffixes:

  In file included from x86_64/hyperv_features.c:13:
  include/x86_64/processor.h:825:9: error: ambiguous instructions require an explicit suffix (could be 'movb', 'movw', 'movl', or 'movq')
          return kvm_asm_safe("wrmsr", "a"(val & -1u), "d"(val >> 32), "c"(msr));
                 ^
  include/x86_64/processor.h:802:15: note: expanded from macro 'kvm_asm_safe'
          asm volatile(KVM_ASM_SAFE(insn)                 \
                       ^
  include/x86_64/processor.h:788:16: note: expanded from macro 'KVM_ASM_SAFE'
          "1: " insn "\n\t"                                       \
                        ^
  <inline asm>:5:2: note: instantiated into assembly here
          mov $0, 15(%rsp)
          ^

It seems like this change could introduce undesirable behavior in the
future, e.g. if someone used a type larger than a u8 for @vector, since
KVM_ASM_SAFE() will only zero the bottom byte. I tried changing the type
of @vector to an int to see what would happen. GCC failed to compile due
to a size mismatch between `movb` and `%eax`. Clang succeeded in
compiling, but the generated code looked correct, so perhaps it will not
be an issue. That being said it seems like there could be a better
solution to this issue that does not assume @vector is a u8.

Fixes: 3b23054cd3 ("KVM: selftests: Add x86-64 support for exception fixup")
Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220722234838.2160385-3-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-08-19 07:38:05 -04:00
David Matlack
67ef8664cc KVM: selftests: Fix KVM_EXCEPTION_MAGIC build with Clang
Change KVM_EXCEPTION_MAGIC to use the all-caps "ULL", rather than lower
case. This fixes a build failure with Clang:

  In file included from x86_64/hyperv_features.c:13:
  include/x86_64/processor.h:825:9: error: unexpected token in argument list
          return kvm_asm_safe("wrmsr", "a"(val & -1u), "d"(val >> 32), "c"(msr));
                 ^
  include/x86_64/processor.h:802:15: note: expanded from macro 'kvm_asm_safe'
          asm volatile(KVM_ASM_SAFE(insn)                 \
                       ^
  include/x86_64/processor.h:785:2: note: expanded from macro 'KVM_ASM_SAFE'
          "mov $" __stringify(KVM_EXCEPTION_MAGIC) ", %%r9\n\t"   \
          ^
  <inline asm>:1:18: note: instantiated into assembly here
          mov $0xabacadabaull, %r9
                          ^

Fixes: 3b23054cd3 ("KVM: selftests: Add x86-64 support for exception fixup")
Signed-off-by: David Matlack <dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220722234838.2160385-2-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-08-19 07:38:05 -04:00
Sean Christopherson
ce30d8b976 KVM: selftests: Verify VMX MSRs can be restored to KVM-supported values
Verify that KVM allows toggling VMX MSR bits to be "more" restrictive,
and also allows restoring each MSR to KVM's original, less restrictive
value.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220607213604.3346000-16-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-07-28 13:25:24 -04:00