[PATCH] nvme/pci: Log PCI_STATUS when the controller dies

[Jens Axboe]

On 11/29/2016 06:18 PM, Andy Lutomirski wrote:
> Signed-off-by: Andy Lutomirski <luto at kernel.org>
> ---
>  drivers/nvme/host/pci.c | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index 0248d0e21fee..b4527e5b1364 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -1292,10 +1292,16 @@ static void nvme_watchdog_timer(unsigned long data)
>  
>  	/* Skip controllers under certain specific conditions. */
>  	if (nvme_should_reset(dev, csts)) {
> -		if (!nvme_reset(dev))
> +		if (!nvme_reset(dev)) {
> +			/* Read a config register to help see what died. */
> +			u16 pci_status = 0xffff;
> +
> +			pci_read_config_word(to_pci_dev(dev->dev),
> +					     PCI_STATUS, &pci_status);
>  			dev_warn(dev->dev,
> -				"Failed status: 0x%x, reset controller.\n",
> -				csts);
> +				"controller is down; will reset: CSTS=0x%x, PCI_STATUS=0x%hx\n",
> +				 csts, pci_status);
> +		}
>  		return;
>  	}

Looks fine to me, but why the pci_status init to 0xffff?

-- 
Jens Axboe