linux-kernel - Re: [PATCH] KVM: x86: Return "unsupported" instead of "invalid" on access to unsupported PV MSR

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <176823890112.1370389.10484759715072723882.b4-ty@google.com>
Date: Mon, 12 Jan 2026 09:38:42 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] KVM: x86: Return "unsupported" instead of "invalid" on
 access to unsupported PV MSR

On Tue, 30 Dec 2025 12:59:48 -0800, Sean Christopherson wrote:
> Return KVM_MSR_RET_UNSUPPORTED instead of '1' (which for all intents and
> purposes means "invalid") when rejecting accesses to KVM PV MSRs to adhere
> to KVM's ABI of allowing host reads and writes of '0' to MSRs that are
> advertised to userspace via KVM_GET_MSR_INDEX_LIST, even if the vCPU model
> doesn't support the MSR.
> 
> E.g. running a QEMU VM with
> 
> [...]

Applied to kvm-x86 misc, thanks!

[1/1] KVM: x86: Return "unsupported" instead of "invalid" on access to unsupported PV MSR
      https://github.com/kvm-x86/linux/commit/5bb9ac186512

--
https://github.com/kvm-x86/linux/tree/next