Re: [PATCH] PCI: vmd: Remove MSI-X check on child devices

[Keith Busch]

On Tue, Aug 12, 2025 at 09:32:19PM +0200, Nam Cao wrote:
> On Tue, Aug 12, 2025 at 02:00:36PM -0500, Bjorn Helgaas wrote:
> > On Tue, Aug 12, 2025 at 08:22:09PM +0200, Nam Cao wrote:
> > > Minor correction, it is not just an unnecessary WARN_ON, but child devices'
> > > drivers couldn't enable MSI at all.
> > > 
> > > So perhaps something like "Remove the sanity check to allow child devices
> > > which only support MSI".
> > 
> > Thanks, updated.
> 
> Sorry for the extra work I have been putting on you this cycle. I trust you
> understand it is for good reason.
> 
> It is unfortunate that I do not have hardware for most patches I sent. The
> best I could do was staring at the patches until I think "yeah, that
> probably isn't broken". That obviously isn't good enough to remove all
> bugs. I wish that I could do better, but oh well...
> 
> Thanks Ammar as well, for helping me tracking down this bug.
> 
> I hope this one is the last regression report that we will see.

I'm sure intel can get you a proper hardware spec. Referencing marketing
white paper material to guide software changes is not a good idea. :)