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| author | Paolo Bonzini <pbonzini@redhat.com> | 2022-02-09 10:56:05 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-02-25 14:20:15 +0100 |
| commit | d6174299365ddbbf491620c0b8c5ca1a6ef2eea5 (patch) | |
| tree | a97f8e14dd4c248e9ab8b645e8d12d8602778e07 /arch/x86/kvm | |
| parent | KVM: selftests: Verify disabling PMU virtualization via KVM_CAP_CONFIG_PMU (diff) | |
| download | linux-d6174299365ddbbf491620c0b8c5ca1a6ef2eea5.tar.xz linux-d6174299365ddbbf491620c0b8c5ca1a6ef2eea5.zip | |
KVM: x86: Reinitialize context if host userspace toggles EFER.LME
While the guest runs, EFER.LME cannot change unless CR0.PG is clear, and
therefore EFER.NX is the only bit that can affect the MMU role. However,
set_efer accepts a host-initiated change to EFER.LME even with CR0.PG=1.
In that case, the MMU has to be reset.
Fixes: 11988499e62b ("KVM: x86: Skip EFER vs. guest CPUID checks for host-initiated writes")
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/mmu.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 3 |
2 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index 51faa2c76ca5..a5a50cfeffff 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -48,6 +48,7 @@ X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_PKE) #define KVM_MMU_CR0_ROLE_BITS (X86_CR0_PG | X86_CR0_WP) +#define KVM_MMU_EFER_ROLE_BITS (EFER_LME | EFER_NX) static __always_inline u64 rsvd_bits(int s, int e) { diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0b95c379e234..b724273493d8 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1648,8 +1648,7 @@ static int set_efer(struct kvm_vcpu *vcpu, struct msr_data *msr_info) return r; } - /* Update reserved bits */ - if ((efer ^ old_efer) & EFER_NX) + if ((efer ^ old_efer) & KVM_MMU_EFER_ROLE_BITS) kvm_mmu_reset_context(vcpu); return 0; |