Re: [PATCH v2] PCI: Disable Samsung SM951/PM951 NVMe before FLR

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, Apr 30, 2021 at 06:01:19PM -0500, Robert Straw wrote:
> The SM951/PM951, when used in conjunction with the vfio-pci driver and
> passed to a KVM guest, can exhibit the fatal state addressed by the
> existing `nvme_disable_and_flr` quirk. If the guest cleanly shuts down
> the SSD, and vfio-pci attempts an FLR to the device while it is in this
> state, the nvme driver will fail when it attempts to bind to the device
> after the FLR due to the frozen config area, e.g:
> 
>   nvme nvme2: frozen state error detected, reset controller
>   nvme nvme2: Removing after probe failure status: -12
> 
> By including this older model (Samsung 950 PRO) of the controller in the
> existing quirk: the device is able to be cleanly reset after being used
> by a KVM guest.
> 
> Signed-off-by: Robert Straw <drbawb@fatalsyntax.com>

Applied to pci/virtualization for v5.14, thanks!

> ---
> changes in v2:
>   - update subject to match style of ffb0863426eb 
> 
>  drivers/pci/quirks.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 653660e3b..e339ca238 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -3920,6 +3920,7 @@ static const struct pci_dev_reset_methods pci_dev_reset_methods[] = {
>  		reset_ivb_igd },
>  	{ PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IVB_M2_VGA,
>  		reset_ivb_igd },
> +	{ PCI_VENDOR_ID_SAMSUNG, 0xa802, nvme_disable_and_flr },
>  	{ PCI_VENDOR_ID_SAMSUNG, 0xa804, nvme_disable_and_flr },
>  	{ PCI_VENDOR_ID_INTEL, 0x0953, delay_250ms_after_flr },
>  	{ PCI_VENDOR_ID_CHELSIO, PCI_ANY_ID,
> -- 
> 2.31.1
>