Assignment of NVIDIA Ampere-based GPUs have seen a regression since the below referenced commit, where the reduced D3hot transition delay appears to introduce a small window where a D3hot->D0 transition followed by a bus reset can wedge the device. The entire device is subsequently unavailable, returning -1 on config space read and is unrecoverable without a host reset. This has been observed with RTX A2000 and A5000 GPU and audio functions assigned to a Windows VM, where shutdown of the VM places the devices in D3hot prior to vfio-pci performing a bus reset when userspace releases the devices. The issue has roughly a 2-3% chance of occurring per shutdown. Restoring the HDA controller d3hot_delay to the effective value before the below commit has been shown to resolve the issue. NVIDIA confirms this change should be safe for all of their HDA controllers. Cc: Abhishek Sahu <abhsahu@xxxxxxxxxx> Cc: Tarun Gupta <targupta@xxxxxxxxxx> Fixes: 3e347969a577 ("PCI/PM: Reduce D3hot delay with usleep_range()") Reported-by: Zhiyi Guo <zhguo@xxxxxxxxxx> Reviewed-by: Tarun Gupta <targupta@xxxxxxxxxx> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> --- Unfortunately Tarun's reply with confirmation doesn't show up on lore, possibly due to html email, or else I'd provide that as a Link:. drivers/pci/quirks.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 44cab813bf95..f4e2a88729fd 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -1939,6 +1939,19 @@ static void quirk_radeon_pm(struct pci_dev *dev) } DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x6741, quirk_radeon_pm); +/* + * NVIDIA Ampere-based HDA controllers can wedge the whole device if a bus + * reset is performed too soon after transition to D0, extend d3hot_delay + * to previous effective default for all NVIDIA HDA controllers. + */ +static void quirk_nvidia_hda_pm(struct pci_dev *dev) +{ + quirk_d3hot_delay(dev, 20); +} +DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, + PCI_CLASS_MULTIMEDIA_HD_AUDIO, 8, + quirk_nvidia_hda_pm); + /* * Ryzen5/7 XHCI controllers fail upon resume from runtime suspend or s2idle. * https://bugzilla.kernel.org/show_bug.cgi?id=205587 -- 2.39.2