Re: [PATCH] PCI: Disable ATS via quirk before notifying IOMMU drivers

[Andy Shevchenko]

On Tue, Feb 24, 2026 at 09:19:05AM -0800, David Matlack wrote:
> On Mon, Feb 23, 2026 at 12:37 PM Andy Shevchenko
> <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> > On Mon, Feb 23, 2026 at 06:40:16PM +0000, David Matlack wrote:

> > > Fix this by disabling ATS via quirk during "early" fixups instead of
> > > "final" fixups.
> >
> > Hmm... Sounds to me like a premature disablement, but I leave it the experts.
> 
> What do you mean by "premature disablement"?

On early stage instead of final stage.


> > What I think about the case, that IOMMU should be probably fixed to avoid such
> > situation for all level of quirks. Can it be feasible?
> 
> What do you mean by the "IOMMU should be fixed"? Are you saying the
> IOMMU should be prepared to handle quirks disabling features on
> devices after the IOMMU driver is notified about a device?

Something like this, yes. At least the commit message is unclear why
"This fixes at least one bug in the Intel IOMMU driver..." not in IOMMU
driver code.


-- 
With Best Regards,
Andy Shevchenko