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authorJim Mattson <jmattson@google.com>2022-09-29 15:52:00 -0700
committerPaolo Bonzini <pbonzini@redhat.com>2022-10-22 07:54:36 -0400
commit7030d8530e533844e2f4b0e7476498afcd324634 (patch)
treed885616d58aa4f34e9535ad8770d1b888ae30f11 /arch/x86/kvm/cpuid.c
parenteeb69eab57c6604ac90b3fd8e5ac43f24a5535b1 (diff)
downloadlinux-7030d8530e533844e2f4b0e7476498afcd324634.tar.bz2
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.c1
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;