[bugzilla-daemon at bugzilla.kernel.org: [Bug 209149] New: "iommu/vt-d: Enable PCI ACS for platform opt in hint" makes NVMe config space not accessible after S3]

[Rajat Jain]

On Wed, Sep 23, 2020 at 9:19 AM Raj, Ashok <ashok.raj at intel.com> wrote:
>
> Hi Bjorn
>
>
> On Wed, Sep 23, 2020 at 11:03:27AM -0500, Bjorn Helgaas wrote:
> > [+cc IOMMU and NVMe folks]
> >
> > Sorry, I forgot to forward this to linux-pci when it was first
> > reported.
> >
> > Apparently this happens with v5.9-rc3, and may be related to
> > 50310600ebda ("iommu/vt-d: Enable PCI ACS for platform opt in hint"),
> > which appeared in v5.8-rc3.
> >
> > There are several dmesg logs and proposed patches in the bugzilla, but
> > no analysis yet of what the problem is.  From the first dmesg
> > attachment (https://bugzilla.kernel.org/attachment.cgi?id=292327):
>
> We have been investigating this internally as well. It appears maybe the
> specupdate for Cometlake is missing the errata documention. The offsets
> were wrong in some of them, and if its the same issue its likely cause.

Can you please also confirm if errata applies to Tigerlake ?

Thanks,

Rajat

>
> Will nudge the hw folks to hunt that down :-(.
>
> Cheers,
> Ashok