diff options
| author | Jim Mattson <jmattson@google.com> | 2022-09-29 15:52:00 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-11-10 17:46:56 +0100 |
| commit | 0e40b4b83e261efd28ac386f68e529d6ea8c1b40 (patch) | |
| tree | 8ef873fdd60fcde7fb4bdd16a816a0302fb4bb2e | |
| parent | 890d738f569fa9412b70ba09f15407f17a52da20 (diff) | |
KVM: x86: Mask off reserved bits in CPUID.80000008H
commit 7030d8530e533844e2f4b0e7476498afcd324634 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 0489ffc3dfe5..768a765c49b0 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -680,6 +680,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, 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; /* * IBRS, IBPB and VIRT_SSBD aren't necessarily present in |