linux-kernel - Re: [PATCH 00/67] KVM: iommu: Overhaul device posted IRQs support

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: <CALzav=d22zi4zzebPJthKGF-uiD3qRTeTJM3Q-LB6UVBiwaAvg@mail.gmail.com>
Date: Fri, 23 May 2025 16:52:20 -0700
From: David Matlack <dmatlack@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>
Cc: Paolo Bonzini <pbonzini@...hat.com>, Joerg Roedel <joro@...tes.org>, 
	David Woodhouse <dwmw2@...radead.org>, Lu Baolu <baolu.lu@...ux.intel.com>, kvm@...r.kernel.org, 
	iommu@...ts.linux.dev, linux-kernel@...r.kernel.org, 
	Maxim Levitsky <mlevitsk@...hat.com>, Joao Martins <joao.m.martins@...cle.com>
Subject: Re: [PATCH 00/67] KVM: iommu: Overhaul device posted IRQs support

On Tue, Apr 8, 2025 at 10:13 AM David Matlack <dmatlack@...gle.com> wrote:
>
> On Fri, Apr 4, 2025 at 12:39 PM Sean Christopherson <seanjc@...gle.com> wrote:
> >
> > This series is well tested except for one notable gap: I was not able to
> > fully test the AMD IOMMU changes.  Long story short, getting upstream
> > kernels into our full test environments is practically infeasible.  And
> > exposing a device or VF on systems that are available to developers is a
> > bit of a mess.
> >
> > The device the selftest (see the last patch) uses is an internel test VF
> > that's hosted on a smart NIC using non-production (test-only) firmware.
> > Unfortunately, only some of our developer systems have the right NIC, and
> > for unknown reasons I couldn't get the test firmware to install cleanly on
> > Rome systems.  I was able to get it functional on Milan (and Intel CPUs),
> > but APIC virtualization is disabled on Milan.  Thanks to KVM's force_avic
> > I could test the KVM flows, but the IOMMU was having none of my attempts
> > to force enable APIC virtualization against its will.
>
> (Sean already knows this but just sharing for the broader visibility.)
>
> I am working on a VFIO selftests framework and helper library that we
> can link into the KVM selftests to make this kind of testing much
> easier. It will support a driver framework so we can support testing
> against different devices in a common way. Developers/companies can
> carry their own out-of-tree drivers for non-standard/custom test
> devices, e.g. the "Mercury device" used in this series.
>
> I will send an RFC in the coming weeks. If/when my proposal is merged,
> then I think we'll have a clean way to get the vfio_irq_test merged
> upstream as well.

This RFC can be found here:
https://lore.kernel.org/kvm/20250523233018.1702151-1-dmatlack@google.com/