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| author | Jim Mattson <jmattson@google.com> | 2022-09-29 15:52:00 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-10-22 07:54:36 -0400 |
| commit | 7030d8530e533844e2f4b0e7476498afcd324634 (patch) | |
| tree | d885616d58aa4f34e9535ad8770d1b888ae30f11 /arch/x86/kvm/cpuid.c | |
| parent | eeb69eab57c6604ac90b3fd8e5ac43f24a5535b1 (diff) | |
| download | lwn-7030d8530e533844e2f4b0e7476498afcd324634.tar.gz lwn-7030d8530e533844e2f4b0e7476498afcd324634.zip | |
KVM: x86: Mask off reserved bits in CPUID.80000008H
KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM
actually supports. The following ranges of CPUID.80000008H are reserved
and should be masked off:
ECX[31:18]
ECX[11:8]
In addition, the PerfTscSize field at ECX[17:16] should also be zero
because KVM does not set the PERFTSC bit at CPUID.80000001H.ECX[27].
Fixes: 24c82e576b78 ("KVM: Sanitize cpuid")
Signed-off-by: Jim Mattson <jmattson@google.com>
Message-Id: <20220929225203.2234702-3-jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/cpuid.c')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 8325a01cb1f1..489c028859e1 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -1169,6 +1169,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) g_phys_as = phys_as; entry->eax = g_phys_as | (virt_as << 8); + entry->ecx &= ~(GENMASK(31, 16) | GENMASK(11, 8)); entry->edx = 0; cpuid_entry_override(entry, CPUID_8000_0008_EBX); break; |