diff options
| author | Sean Christopherson <seanjc@google.com> | 2021-04-06 10:18:11 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-04-20 04:18:50 -0400 |
| commit | 44f1b5586df03b044704f3c57f529ea4120f406b (patch) | |
| tree | e03d240817dad9b0439cf4d248838b7e2c3b0e82 /arch/x86 | |
| parent | 554cf31474937f0a78045aaa7df565ffb6a29c43 (diff) | |
| download | lwn-44f1b5586df03b044704f3c57f529ea4120f406b.tar.gz lwn-44f1b5586df03b044704f3c57f529ea4120f406b.zip | |
KVM: SVM: Enhance and clean up the vmcb tracking comment in pre_svm_run()
Explicitly document why a vmcb must be marked dirty and assigned a new
asid when it will be run on a different cpu. The "what" is relatively
obvious, whereas the "why" requires reading the APM and/or KVM code.
Opportunistically remove a spurious period and several unnecessary
newlines in the comment.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210406171811.4043363-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 1207526cf8e7..5f1af4163251 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -3336,11 +3336,10 @@ static void pre_svm_run(struct kvm_vcpu *vcpu) struct vcpu_svm *svm = to_svm(vcpu); /* - * If the previous vmrun of the vmcb occurred on - * a different physical cpu then we must mark the vmcb dirty. - * and assign a new asid. - */ - + * If the previous vmrun of the vmcb occurred on a different physical + * cpu, then mark the vmcb dirty and assign a new asid. Hardware's + * vmcb clean bits are per logical CPU, as are KVM's asid assignments. + */ if (unlikely(svm->current_vmcb->cpu != vcpu->cpu)) { svm->current_vmcb->asid_generation = 0; vmcb_mark_all_dirty(svm->vmcb); |