Commit Graph

11 Commits

Author SHA1 Message Date
Sean Christopherson
3b2d3db368 KVM: selftests: Fix printf() format goof in SEV smoke test
Print out the index of mismatching XSAVE bytes using unsigned decimal
format.  Some versions of clang complain about trying to print an integer
as an unsigned char.

  x86/sev_smoke_test.c:55:51: error: format specifies type 'unsigned char'
                                     but the argument has type 'int' [-Werror,-Wformat]

Fixes: 8c53183dba ("selftests: kvm: add test for transferring FPU state into VMSA")
Link: https://lore.kernel.org/r/20250228233852.3855676-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-03-03 07:45:34 -08:00
Sean Christopherson
f3513a335e KVM: selftests: Assert that STI blocking isn't set after event injection
Add an L1 (guest) assert to the nested exceptions test to verify that KVM
doesn't put VMRUN in an STI shadow (AMD CPUs bleed the shadow into the
guest's int_state if a #VMEXIT occurs before VMRUN fully completes).

Add a similar assert to the VMX side as well, because why not.

Reviewed-by: Jim Mattson <jmattson@google.com>
Link: https://lore.kernel.org/r/20250224165442.2338294-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-28 09:15:23 -08:00
Sean Christopherson
e36454461c KVM: selftests: Add CPUID tests for Hyper-V features that need in-kernel APIC
Add testcases to x86's Hyper-V CPUID test to verify that KVM advertises
support for features that require an in-kernel local APIC appropriately,
i.e. that KVM hides support from the vCPU-scoped ioctl if the VM doesn't
have an in-kernel local APIC.

Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20250118003454.2619573-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-12 08:55:11 -08:00
Sean Christopherson
cd5a0c2f0f KVM: selftests: Manage CPUID array in Hyper-V CPUID test's core helper
Allocate, get, and free the CPUID array in the Hyper-V CPUID test in the
test's core helper, instead of copy+pasting code at each call site.  In
addition to deduplicating a small amount of code, restricting visibility
of the array to a single invocation of the core test prevents "leaking" an
array across test cases.  Passing in @vcpu to the helper will also allow
pivoting on VM-scoped information without needing to pass more booleans,
e.g. to conditionally assert on features that require an in-kernel APIC.

To avoid use-after-free bugs due to overzealous and careless developers,
opportunstically add a comment to explain that the system-scoped helper
caches the Hyper-V CPUID entries, i.e. that the caller is not responsible
for freeing the memory.

Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20250118003454.2619573-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-12 08:53:59 -08:00
Sean Christopherson
0b6db0dc43 KVM: selftests: Mark test_hv_cpuid_e2big() static in Hyper-V CPUID test
Make the Hyper-V CPUID test's local helper test_hv_cpuid_e2big() static,
it's not used outside of the test (and isn't intended to be).

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20250118003454.2619573-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-02-12 08:53:57 -08:00
Ivan Orlov
4e9427aeb9 KVM: selftests: Add and use a helper function for x86's LIDT
Implement a function for setting the IDT descriptor from the guest
code. Replace the existing lidt occurrences with calls to this function
as `lidt` is used in multiple places.

Signed-off-by: Ivan Orlov <iorlov@amazon.com>
Link: https://lore.kernel.org/r/20241217181458.68690-7-iorlov@amazon.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18 15:14:46 -08:00
Sean Christopherson
59cb3acdb3 KVM: selftests: Update x86's KVM PV test to match KVM's disabling exits behavior
Rework x86's KVM PV features test to align with KVM's new, fixed behavior
of not allowing userspace to disable HLT-exiting after vCPUs have been
created.  Rework the core testcase to disable HLT-exiting before creating
a vCPU, and opportunistically modify keep the paired VM+vCPU creation to
verify that KVM rejects KVM_CAP_X86_DISABLE_EXITS as expected.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20241128013424.4096668-18-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18 14:19:39 -08:00
Sean Christopherson
7b2658cb33 KVM: selftests: Fix a bad TEST_REQUIRE() in x86's KVM PV test
Actually check for KVM support for disabling HLT-exiting instead of
effectively checking that KVM_CAP_X86_DISABLE_EXITS is #defined to a
non-zero value, and convert the TEST_REQUIRE() to a simple return so
that only the sub-test is skipped if HLT-exiting is mandatory.

The goof has likely gone unnoticed because all x86 CPUs support disabling
HLT-exiting, only systems with the opt-in mitigate_smt_rsb KVM module
param disallow HLT-exiting.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20241128013424.4096668-17-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18 14:19:38 -08:00
Sean Christopherson
01bcd829c6 KVM: selftests: Verify KVM stuffs runtime CPUID OS bits on CR4 writes
Extend x86's set sregs test to verify that KVM sets/clears OSXSAVE and
OSKPKE according to CR4.XSAVE and CR4.PKE respectively.  For performance
reasons, KVM is responsible for emulating the architectural behavior of
the OS CPUID bits tracking CR4.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20241128013424.4096668-10-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18 14:19:31 -08:00
Sean Christopherson
bf4dfc3aa8 KVM: selftests: Update x86's set_sregs_test to match KVM's CPUID enforcement
Rework x86's set sregs test to verify that KVM enforces CPUID vs. CR4
features even if userspace hasn't explicitly set guest CPUID.  KVM used to
allow userspace to set any KVM-supported CR4 value prior to KVM_SET_CPUID2,
and the test verified that behavior.

However, the testcase was written purely to verify KVM's existing behavior,
i.e. was NOT written to match the needs of real world VMMs.

Opportunistically verify that KVM continues to reject unsupported features
after KVM_SET_CPUID2 (using KVM_GET_SUPPORTED_CPUID).

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20241128013424.4096668-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18 14:19:27 -08:00
Sean Christopherson
67730e6c53 KVM: selftests: Use canonical $(ARCH) paths for KVM selftests directories
Use the kernel's canonical $(ARCH) paths instead of the raw target triple
for KVM selftests directories.  KVM selftests are quite nearly the only
place in the entire kernel that using the target triple for directories,
tools/testing/selftests/drivers/s390x being the lone holdout.

Using the kernel's preferred nomenclature eliminates the minor, but
annoying, friction of having to translate to KVM's selftests directories,
e.g. for pattern matching, opening files, running selftests, etc.

Opportunsitically delete file comments that reference the full path of the
file, as they are obviously prone to becoming stale, and serve no known
purpose.

Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20241128005547.4077116-16-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-12-18 14:15:04 -08:00