Hi, On kernel 6.6.x, with an ASMedia ASM1062 (AHCI) controller, on an ASUSTeK Pro WS WRX80E-SAGE SE WIFI mainboard, PCI ID 1b21:0612 and subsystem ID 1043:858d, I got a total apparent controller hang, rendering the two attached SATA devices unavailable, that was immediately preceded by the following kernel messages: [Thu Jan 4 23:12:54 2024] ahci 0000:28:00.0: Using 64-bit DMA addresses [Thu Jan 4 23:12:54 2024] ahci 0000:28:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0035 address=0x7fffff00000 flags=0x0000] [Thu Jan 4 23:12:54 2024] ahci 0000:28:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0035 address=0x7fffff00300 flags=0x0000] [Thu Jan 4 23:12:54 2024] ahci 0000:28:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0035 address=0x7fffff00380 flags=0x0000] [Thu Jan 4 23:12:54 2024] ahci 0000:28:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0035 address=0x7fffff00400 flags=0x0000] [Thu Jan 4 23:12:54 2024] ahci 0000:28:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0035 address=0x7fffff00680 flags=0x0000] [Thu Jan 4 23:12:54 2024] ahci 0000:28:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0035 address=0x7fffff00700 flags=0x0000] It seems as if the controller has problems with 64-bit DMA addresses, and the comments around the source of the message in drivers/iommu/dma-iommu.c seem to point into that same direction: /* * Try to use all the 32-bit PCI addresses first. The original SAC vs. * DAC reasoning loses relevance with PCIe, but enough hardware and * firmware bugs are still lurking out there that it's safest not to * venture into the 64-bit space until necessary. * * If your device goes wrong after seeing the notice then likely either * its driver is not setting DMA masks accurately, the hardware has * some inherent bug in handling >32-bit addresses, or not all the * expected address bits are wired up between the device and the IOMMU. */ if (dma_limit > DMA_BIT_MASK(32) && dev->iommu->pci_32bit_workaround) { iova = alloc_iova_fast(iovad, iova_len, DMA_BIT_MASK(32) >> shift, false); if (iova) goto done; dev->iommu->pci_32bit_workaround = false; dev_notice(dev, "Using %d-bit DMA addresses\n", bits_per(dma_limit)); } Are there any tests you can think of that I can run to further narrow down this issue? By itself, the issue reproduces only rarely. Thank you in advance. Kind regards, Lennert