Re: [BUG] skge: a possible sleep-in-atomic bug in skge_remove

From: Stephen Hemminger
Date: Tue Dec 12 2017 - 13:22:48 EST


On Tue, 12 Dec 2017 08:34:45 -0500 (EST)
David Miller <davem@xxxxxxxxxxxxx> wrote:

> From: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
> Date: Tue, 12 Dec 2017 16:38:12 +0800
>
> > According to drivers/net/ethernet/marvell/skge.c, the driver may sleep
> > under a spinlock.
> > The function call path is:
> > skge_remove (acquire the spinlock)
> > free_irq --> may sleep
> >
> > I do not find a good way to fix it, so I only report.
> > This possible bug is found by my static analysis tool (DSAC) and
> > checked by my code review.
>
> This was added by:
>
> commit a9e9fd7182332d0cf5f3e601df3e71dd431b70d7
> Author: Stephen Hemminger <shemminger@xxxxxxxxxx>
> Date: Tue Sep 27 13:41:37 2011 -0400
>
> skge: handle irq better on single port card
>
> I think the free_irq() can be moved below the unlock.
>
> Stephen, please take a look.

The IRQ was being free twice.
How did you see it, I really doubt any multi-port SKGE cards
still exist.