[+cc Alex] This claims to be a resend, but I don't see a previous posting. There *was* discussion when the quirk was added two years ago for a different device. As part of that, Alex thought only that device would be affected and ATS was validated on other GPUs: https://lore.kernel.org/lkml/BN6PR12MB165278346BE8A76B1E4412AFF7EA0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ On Mon, Apr 08, 2019 at 01:37:25PM +0300, Nikolai Kostrigin wrote: > ATS is broken on this hardware (at least for Stoney Ridge > based laptop) and causes IOMMU stalls and > system failure. Disable ATS on these devices to make them > usable again with IOMMU enabled > Thanks to Joerg Roedel <jroedel@xxxxxxx> for help. > > https://bugzilla.kernel.org/show_bug.cgi?id=194521 > > Signed-off-by: Nikolai Kostrigin <nickel@xxxxxxxxxxxx> Joerg, I'm happy to merge this if you would review or ack it. I don't know enough to conclude that this is the root cause. It'd be nice to have an actual AMD erratum. Maybe it would even have a list of affected devices so we could get them all at once so people wouldn't have to trip over them one by one. > --- > drivers/pci/quirks.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c > index 4700d24e5d55..abb2532e16bf 100644 > --- a/drivers/pci/quirks.c > +++ b/drivers/pci/quirks.c > @@ -4876,6 +4876,7 @@ static void quirk_no_ats(struct pci_dev *pdev) > > /* AMD Stoney platform GPU */ > DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x98e4, quirk_no_ats); > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x6900, quirk_no_ats); > #endif /* CONFIG_PCI_ATS */ > > /* Freescale PCIe doesn't support MSI in RC mode */ > -- > 2.21.0 >
