On 11.01.23 09:57, Christian König wrote: > This reverts commit 201007ef707a8bb5592cd07dd46fc9222c48e0b9. > > It's correct that the PCIe fabric routes Memory Requests based on the > TLP address, but enabling the PASID mapping doesn't necessary mean that > Memory Requests will have a PASID associated with them. > > The alternative is ATS which lets the device resolve the PASID+addr pair > before a memory request is made into a routeable TLB address through the > TA. Those resolved addresses are then cached on the device instead of > in the IOMMU TLB. > > So the assumption that you mandatory need ACS to enabled PASID handling > on a device is simply not correct, we need to take ATS into account as > well. > > The patch caused failures with AMDs integrated GPUs because some of them > only enable ATS but not ACS. > > For now just revert the patch until this is completely solved. > > CC: Jason Gunthorpe <jgg@xxxxxxxxxx> > CC: Kevin Tian <kevin.tian@xxxxxxxxx> > CC: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> > CC: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > CC: Tony Zhu <tony.zhu@xxxxxxxxx> > CC: Joerg Roedel <jroedel@xxxxxxx> > Signed-off-by: Christian König <christian.koenig@xxxxxxx> One small thing to improve: > Bug: https://bugzilla.kernel.org/show_bug.cgi?id=216865 s/Bug:/Link:/ here, otherwise you might get mails from Linus like these: https://lore.kernel.org/all/CAHk-=wjMmSZzMJ3Xnskdg4+GGz=5p5p+GSYyFBTh0f-DgvdBWg@xxxxxxxxxxxxxx/ https://lore.kernel.org/all/CAHk-=wgs38ZrfPvy=nOwVkVzjpM3VFU1zobP37Fwd_h9iAD5JQ@xxxxxxxxxxxxxx/ https://lore.kernel.org/all/CAHk-=wjxzafG-=J8oT30s7upn4RhBs6TX-uVFZ5rME+L5_DoJA@xxxxxxxxxxxxxx/ This usage is also explained in Documentation/process/submitting-patches.rst (http://docs.kernel.org/process/submitting-patches.html) and Documentation/process/5.Posting.rst (https://docs.kernel.org/process/5.Posting.html) Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) -- Everything you wanna know about Linux kernel regression tracking: https://linux-regtracking.leemhuis.info/about/#tldr If I did something stupid, please tell me, as explained on that page. P.S.: let me tell regzbot to monitor this thread: #regzbot ^backmonitor: https://bugzilla.kernel.org/show_bug.cgi?id=216865
