Re: [PATCH] PCI: Disable bus reset for ASM1164 SATA controller

[Bjorn Helgaas <helgaas@kernel.org>]

On Thu, Jan 08, 2026 at 05:02:08PM -0700, Alex Williamson wrote:
> User forums report issues when assigning ASM1164 SATA controllers to
> VMs, especially in configurations with multiple controllers.  Logs
> show the device fails to retrain after bus reset.  Reports suggest
> this is an issue across multiple platforms.  The device indicates
> support for PM reset, therefore the device still has a viable function
> level reset mechanism.  The reporting user confirms the device is well
> behaved in this use case with bus reset disabled.
> 
> Reported-by: Patrick Bianchi <patrick.w.bianchi@gmail.com>
> Link: https://forum.proxmox.com/threads/problems-with-pcie-passthrough-with-two-identical-devices.149003/
> Signed-off-by: Alex Williamson <alex.williamson@nvidia.com>

Applied to pci/virtualization for v6.20, thanks!

> ---
>  drivers/pci/quirks.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index b9c252aa6fe0..3a8d5622ee2b 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -3791,6 +3791,16 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CAVIUM, 0xa100, quirk_no_bus_reset);
>   */
>  DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TI, 0xb005, quirk_no_bus_reset);
>  
> +/*
> + * Reports from users making use of PCI device assignment with ASM1164
> + * controllers indicate an issue with bus reset where the device fails to
> + * retrain.  The issue appears more common in configurations with multiple
> + * controllers.  The device does indicate PM reset support (NoSoftRst-),
> + * therefore this still leaves a viable reset method.
> + * https://forum.proxmox.com/threads/problems-with-pcie-passthrough-with-two-identical-devices.149003/
> + */
> +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ASMEDIA, 0x1164, quirk_no_bus_reset);
> +
>  static void quirk_no_pm_reset(struct pci_dev *dev)
>  {
>  	/*
> -- 
> 2.51.0
>