Re: [PATCH v2 0/4] KVM: SVM: Fix unexpected #UD on INT3 in SEV guests

From: Tom Lendacky
Date: Fri Aug 25 2023 - 17:35:46 EST


On 8/25/23 14:02, Sean Christopherson wrote:
On Thu, 24 Aug 2023 18:36:17 -0700, Sean Christopherson wrote:
Fix a bug where KVM injects a bogus #UD for SEV guests when trying to skip
an INT3 as part of re-injecting the associated #BP that got kinda sorta
intercepted due to a #NPF occuring while vectoring/delivering the #BP.

Patch 1 is the main fix. It's a little ugly, but suitable for backporting.

Patch 2 is a tangentially related cleanup to make NRIPS a requirement for
enabling SEV, e.g. so that we don't ever get "bug" reports of SEV guests
not working when NRIPS is disabled.

[...]

Applied 1 and 2 to kvm-x86 svm, the more aggressive cleanup can definitely wait
until 6.7.

[1/4] KVM: SVM: Don't inject #UD if KVM attempts to skip SEV guest insn
https://github.com/kvm-x86/linux/commit/cb49631ad111
[2/4] KVM: SVM: Require nrips support for SEV guests (and beyond)
https://github.com/kvm-x86/linux/commit/80d0f521d59e

Thanks, Sean!

I'm taking it through our testing and will let know if anything pops up. Since you have a recreate I don't expect anything, though.

Thanks,
Tom


--
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