On Thu, Jan 25, 2024 at 05:04:01PM +0200, Lennert Buytenhek wrote: > With one of the on-board ASM1061 AHCI controllers (1b21:0612) on an > ASUSTeK Pro WS WRX80E-SAGE SE WIFI mainboard, a controller hang was > observed 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] > > The first message is produced by code in drivers/iommu/dma-iommu.c > which is accompanied by the following comment that seems to apply: > > /* > * 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. > */ > > Asking the ASM1061 on a discrete PCIe card to DMA from I/O virtual > address 0xffffffff00000000 produces the following I/O page faults: > > [Tue Jan 23 21:31:55 2024] vfio-pci 0000:07:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0021 address=0x7ff00000000 flags=0x0010] > [Tue Jan 23 21:31:55 2024] vfio-pci 0000:07:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x0021 address=0x7ff00000500 flags=0x0010] > > Note that the upper 21 bits of the logged DMA address are zero. (When > asking a different PCIe device in the same PCIe slot to DMA to the > same I/O virtual address, we do see all the upper 32 bits of the DMA > address as 1, so this is not an issue with the chipset or IOMMU > configuration on the test system.) > > Also, hacking libahci to always set the upper 21 bits of all DMA > addresses to 1 produces no discernible effect on the behavior of the > ASM1061, and mkfs/mount/scrub/etc work as without this hack. > > This all strongly suggests that the ASM1061 has a 43 bit DMA address > limit, and this commit therefore adds a quirk to deal with this limit. > > This issue probably applies to (some of) the other supported ASMedia > parts as well, but we limit it to the PCI IDs known to refer to > ASM1061 parts, as that's the only part we know for sure to be affected > by this issue at this point. > > Link: https://lore.kernel.org/linux-ide/ZaZ2PIpEId-rl6jv@xxxxxxxxxxxxxx/ > Signed-off-by: Lennert Buytenhek <kernel@xxxxxxxxxxxxxx> > --- Applied: https://git.kernel.org/pub/scm/linux/kernel/git/libata/linux.git/log/?h=for-6.8-fixes
