From: Sean Christopherson <seanjc@google.com>
To: Nikunj A Dadhania <nikunj@amd.com>
Cc: pbonzini@redhat.com, kvm@vger.kernel.org,
thomas.lendacky@amd.com, santosh.shukla@amd.com, bp@alien8.de,
Michael Roth <michael.roth@amd.com>,
stable@vger.kernel.org
Subject: Re: [PATCH] KVM: SEV: Enforce minimum GHCB version requirement for SEV-SNP guests
Date: Mon, 14 Jul 2025 07:29:44 -0700 [thread overview]
Message-ID: <aHUUWMnTBfcRO7Uj@google.com> (raw)
In-Reply-To: <85ple4go0k.fsf@amd.com>
On Sun, Jul 13, 2025, Nikunj A Dadhania wrote:
> Sean Christopherson <seanjc@google.com> writes:
>
> > On Fri, Jul 11, 2025, Nikunj A Dadhania wrote:
> >> Require a minimum GHCB version of 2 when starting SEV-SNP guests through
> >> KVM_SEV_INIT2. When a VMM attempts to start an SEV-SNP guest with an
> >> incompatible GHCB version (less than 2), reject the request early rather
> >> than allowing the guest to start with an incorrect protocol version and
> >> fail later.
> >
> > What happens with ghcb_version==1? I.e. what failure occurs, and
> > when?
>
> SNP guest terminates with following error:
So this probably isn't stable@ worth then? Because I don't see any risk to the
kernel, this is ultimately only a problem if the VMM is broken, and the "fix"
doesn't provide any meaningful change in functionality (the VM is dead no matter
what).
next prev parent reply other threads:[~2025-07-14 14:29 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-11 4:54 [PATCH] KVM: SEV: Enforce minimum GHCB version requirement for SEV-SNP guests Nikunj A Dadhania
2025-07-11 13:07 ` Sean Christopherson
2025-07-13 14:32 ` Nikunj A Dadhania
2025-07-14 14:29 ` Sean Christopherson [this message]
2025-07-15 6:08 ` Nikunj A Dadhania
2025-07-11 21:42 ` kernel test robot
2025-07-13 14:33 ` Nikunj A Dadhania
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