Messages in this thread | | | Subject | Re: [PATCH] KVM: SVM: Make sure GHCB is mapped before updating | From | Paolo Bonzini <> | Date | Thu, 8 Apr 2021 18:14:27 +0200 |
| |
On 08/04/21 18:04, Tom Lendacky wrote: >>>> + if (!err || !sev_es_guest(vcpu->kvm) || !WARN_ON_ONCE(svm->ghcb)) >>> This should be WARN_ON_ONCE(!svm->ghcb), otherwise you'll get the right >>> result, but get a stack trace immediately. >> Doh, yep. > Actually, because of the "or's", this needs to be: > > if (!err || !sev_es_guest(vcpu->kvm) || (sev_es_guest(vcpu->kvm) && WARN_ON_ONCE(!svm->ghcb)))
No, || cuts the right-hand side if the left-hand side is true. So:
- if err == 0, the rest is not evaluated
- if !sev_es_guest(vcpu->kvm), WARN_ON_ONCE(!svm->ghcb) is not evaluated
Paolo
| |