KVM: SVM: Delay restoration of host MSR_TSC_AUX until return to userspace

Browse source

Use KVM's "user return MSRs" framework to defer restoring the host's
MSR_TSC_AUX until the CPU returns to userspace.  Add/improve comments to
clarify why MSR_TSC_AUX is intercepted on both RDMSR and WRMSR, and why
it's safe for KVM to keep the guest's value loaded even if KVM is
scheduled out.

Cc: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210423223404.3860547-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

...

This commit is contained in:

Sean Christopherson 2021-04-23 15:34:04 -07:00 • committed by Paolo Bonzini

parent dbd6127375

commit 844d69c26d

2 changed files with 24 additions and 36 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

53

arch/x86/kvm/svm/svm.c

View file

7

arch/x86/kvm/svm/svm.h

View file