diff options
author | Sean Christopherson <seanjc@google.com> | 2021-05-04 10:17:24 -0700 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-05-07 06:06:16 -0400 |
commit | 5104d7ffcf24749939bea7fdb5378d186473f890 (patch) | |
tree | 4edd4687d7b6aa480446cd8d5942037fb203b141 /arch/x86/include/asm | |
parent | 2183de4161b90bd3851ccd3910c87b2c9adfc6ed (diff) |
KVM: VMX: Disable preemption when probing user return MSRs
Disable preemption when probing a user return MSR via RDSMR/WRMSR. If
the MSR holds a different value per logical CPU, the WRMSR could corrupt
the host's value if KVM is preempted between the RDMSR and WRMSR, and
then rescheduled on a different CPU.
Opportunistically land the helper in common x86, SVM will use the helper
in a future commit.
Fixes: 4be534102624 ("KVM: VMX: Initialize vmx->guest_msrs[] right after allocation")
Cc: stable@vger.kernel.org
Cc: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210504171734.1434054-6-seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include/asm')
-rw-r--r-- | arch/x86/include/asm/kvm_host.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 848956bb3cf1..e8dcbc632cf8 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1777,6 +1777,7 @@ int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low, unsigned long icr, int op_64_bit); void kvm_define_user_return_msr(unsigned index, u32 msr); +int kvm_probe_user_return_msr(u32 msr); int kvm_set_user_return_msr(unsigned index, u64 val, u64 mask); u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc); |