> From: Baolu Lu <baolu.lu@xxxxxxxxxxxxxxx> > Sent: Thursday, November 16, 2023 3:25 PM > > On 2023/11/16 11:27, Tian, Kevin wrote: > >> From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> > >> Sent: Thursday, November 16, 2023 10:23 AM > >> > >> @@ -5080,7 +5080,7 @@ static void quirk_igfx_skip_te_disable(struct > >> pci_dev *dev) > >> ver = (dev->device >> 8) & 0xff; > >> if (ver != 0x45 && ver != 0x46 && ver != 0x4c && > >> ver != 0x4e && ver != 0x8a && ver != 0x98 && > >> - ver != 0x9a && ver != 0xa7) > >> + ver != 0x9a && ver != 0xa7 && ver != 0x7d) > >> return; > >> > > > > this fix alone is fine, but I found this quirk overall is not cleanly handled. > > > > Basically it sets iommu_skip_te_disable as true, leading to early return > > in iommu_disable_translation(): > > > > if (iommu_skip_te_disable && iommu->drhd->gfx_dedicated && > > (cap_read_drain(iommu->cap) || cap_write_drain(iommu->cap))) > > return; > > > > However the caller of iommu_disable_translation() is not aware of this > > quirk and continues as if the iommu is disabled. IMHO this is problematic > > w/o meeting the caller's assumption. > > > > e.g. kdump and suspend. We may want to abort those paths early in case > > of such quirk... > > I can see your point. > > This fix is just to add a new device model to the established quirk > list. All devices (including the new one) in this quirk list have > undergone thorough verification. Therefor, I'd like to keep it as-is. > > We can refine the quirk implementation in a separated patch series with > sufficient consideration and verification. Does this work for you? sure
