diff options
| author | Sean Christopherson <seanjc@google.com> | 2021-04-06 10:18:08 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-04-20 04:18:49 -0400 |
| commit | 17e5e964eee05a3ee434cf0958ecce741a6874b1 (patch) | |
| tree | 016d1079d666a891c5c909baf866dfb1064ae245 /arch | |
| parent | a3ba26ecfb569f4aa3f867e80c02aa65f20aadad (diff) | |
KVM: SVM: Don't set current_vmcb->cpu when switching vmcb
Do not update the new vmcb's last-run cpu when switching to a different
vmcb. If the vCPU is migrated between its last run and a vmcb switch,
e.g. for nested VM-Exit, then setting the cpu without marking the vmcb
dirty will lead to KVM running the vCPU on a different physical cpu with
stale clean bit settings.
vcpu->cpu current_vmcb->cpu hardware
pre_svm_run() cpu0 cpu0 cpu0,clean
kvm_arch_vcpu_load() cpu1 cpu0 cpu0,clean
svm_switch_vmcb() cpu1 cpu1 cpu0,clean
pre_svm_run() cpu1 cpu1 kaboom
Simply delete the offending code; unlike VMX, which needs to update the
cpu at switch time due to the need to do VMPTRLD, SVM only cares about
which cpu last ran the vCPU.
Fixes: af18fa775d07 ("KVM: nSVM: Track the physical cpu of the vmcb vmrun through the vmcb")
Cc: Cathy Avery <cavery@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210406171811.4043363-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 8 |
1 files changed, 0 insertions, 8 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 4fc1f16505db..04ef49d3862d 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1311,14 +1311,6 @@ void svm_switch_vmcb(struct vcpu_svm *svm, struct kvm_vmcb_info *target_vmcb) svm->current_vmcb = target_vmcb; svm->vmcb = target_vmcb->ptr; svm->vmcb_pa = target_vmcb->pa; - - /* - * Track the physical CPU the target_vmcb is running on - * in order to mark the VMCB dirty if the cpu changes at - * its next vmrun. - */ - - svm->current_vmcb->cpu = svm->vcpu.cpu; } static int svm_create_vcpu(struct kvm_vcpu *vcpu) |