linux-kernel - Re: [PATCH 0/5] KVM: VMX: Fix MMIO Stale Data Mitigation

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

Message-ID: <20250603012208.cadagk7rgwy24gkh@desk>
Date: Mon, 2 Jun 2025 18:22:08 -0700
From: Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>
To: Sean Christopherson <seanjc@...gle.com>
Cc: Paolo Bonzini <pbonzini@...hat.com>, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org, Borislav Petkov <bp@...en8.de>,
	Jim Mattson <jmattson@...gle.com>
Subject: Re: [PATCH 0/5] KVM: VMX: Fix MMIO Stale Data Mitigation

On Mon, Jun 02, 2025 at 04:41:35PM -0700, Sean Christopherson wrote:
> > Regarding validating this, if VERW is executed at VMenter, mitigation was
> > found to be effective. This is similar to other bugs like MDS. I am not a
> > virtualization expert, but I will try to validate whatever I can.
> 
> If you can re-verify the mitigation works for VFIO devices, that's more than
> good enough for me.  The bar at this point is to not regress the existing mitigation,
> anything beyond that is gravy.

Ok sure. I'll verify that VERW is getting executed for VFIO devices.

> I've verified the KVM mechanics of tracing MMIO mappings fairly well (famous last
> words), the only thing I haven't sanity checked is that the existing coverage for
> VFIO devices is maintained.