On 09/29/2015 at 06:20 PM, Joerg Roedel wrote: > On Tue, Sep 29, 2015 at 11:58:10AM -0400, Mikulas Patocka wrote: >> On Tue, 29 Sep 2015, Joerg Roedel wrote: >> There was a patch (34b48db66e08ca1c1bc07cf305d672ac940268dc) that >> increased default block request size. That patch triggers AMD-Vi page >> faults. The bug may be in ATA driver, in ATA controller on in AMD-Vi >> driver or hardware. I didn't see anything in that thread that proves that >> the bug in not in AMD-Vi IOMMU. >> >> The bug probably existed even before kernel 3.19, but it was masked by the >> fact that I/O request size was artifically capped. Bisecting probably >> won't find it, as it may have existed since ever. > > Okay, I see. But as long as the request-size is not bigger than 128MB > (the biggest chunk the AMD IOMMU driver can map at once), I don't see > how the IOMMU driver could be at fault. > > Which ATA driver is in use when this happens and are there instructions > on how to reproduce the issue? > > Alternativly someone who can reproduce it should trace the calls to > __map_single and __unmap_single in the AMD IOMMU driver to find out > whether the addresses which the faults happen on are really mapped, or > at least requested from the AMD IOMMU driver. How can I trace it? Thanks, Andreas -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
