Re: [PATCH/RFC net v2] net: dec: tulip: de2104x: Add shutdown handler to stop NIC

From: Jakub Kicinski
Date: Fri Oct 23 2020 - 16:08:20 EST


On Thu, 22 Oct 2020 19:45:20 -0700 Moritz Fischer wrote:
> The driver does not implement a shutdown handler which leads to issues
> when using kexec in certain scenarios. The NIC keeps on fetching
> descriptors which gets flagged by the IOMMU with errors like this:
>
> DMAR: DMAR:[DMA read] Request device [5e:00.0]fault addr fffff000
> DMAR: DMAR:[DMA read] Request device [5e:00.0]fault addr fffff000
> DMAR: DMAR:[DMA read] Request device [5e:00.0]fault addr fffff000
> DMAR: DMAR:[DMA read] Request device [5e:00.0]fault addr fffff000
> DMAR: DMAR:[DMA read] Request device [5e:00.0]fault addr fffff000
>
> Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx>

Change looks good.

Philosophically speaking I wonder if this is a fix or a feature.
If missing .shutdown callback was a bug we shouldn't accept drivers
which don't specify it :S

If you don't have a strong preference I'd rather apply this to net-next.

In any case - you need to respin, 'cause this does not apply to net
either :)

> diff --git a/drivers/net/ethernet/dec/tulip/de2104x.c b/drivers/net/ethernet/dec/tulip/de2104x.c
> index f1a2da15dd0a..6de0cd6cf4ca 100644
> --- a/drivers/net/ethernet/dec/tulip/de2104x.c
> +++ b/drivers/net/ethernet/dec/tulip/de2104x.c
> @@ -2180,11 +2180,19 @@ static int de_resume (struct pci_dev *pdev)
>
> #endif /* CONFIG_PM */
>
> +static void de_shutdown(struct pci_dev *pdev)
> +{
> + struct net_device *dev = pci_get_drvdata (pdev);

No space needed before parens

> +
> + de_close(dev);
> +}
> +
> static struct pci_driver de_driver = {
> .name = DRV_NAME,
> .id_table = de_pci_tbl,
> .probe = de_init_one,
> .remove = de_remove_one,
> + .shutdown = de_shutdown,
> #ifdef CONFIG_PM
> .suspend = de_suspend,
> .resume = de_resume,