From 63ba51db24ed1b8f8088a897290eb6c036c5435d Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Sat, 28 Jan 2023 10:39:51 +0900 Subject: [PATCH] PCI: Avoid FLR for AMD FCH AHCI adapters PCI passthrough to VMs does not work with AMD FCH AHCI adapters: the guest OS fails to correctly probe devices attached to the controller due to FIS communication failures: ata4: softreset failed (1st FIS failed) ... ata4.00: qc timeout after 5000 msecs (cmd 0xec) ata4.00: failed to IDENTIFY (I/O error, err_mask=0x4) Forcing the "bus" reset method before unbinding & binding the adapter to the vfio-pci driver solves this issue, e.g.: echo "bus" > /sys/bus/pci/devices//reset_method gives a working guest OS, indicating that the default FLR reset method doesn't work correctly. Apply quirk_no_flr() to AMD FCH AHCI devices to work around this issue. Link: https://lore.kernel.org/r/20230128013951.523247-1-damien.lemoal@opensource.wdc.com Reported-by: Niklas Cassel Signed-off-by: Damien Le Moal Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org --- drivers/pci/quirks.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 285acc4aaccc..20ac67d59034 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -5340,6 +5340,7 @@ static void quirk_no_flr(struct pci_dev *dev) DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_AMD, 0x1487, quirk_no_flr); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_AMD, 0x148c, quirk_no_flr); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_AMD, 0x149c, quirk_no_flr); +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_AMD, 0x7901, quirk_no_flr); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1502, quirk_no_flr); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x1503, quirk_no_flr);