Re: [PATCH] net: cadence: Fix a sleep-in-atomic-context bug in macb_halt_tx()

From: David Miller
Date: Sun Sep 02 2018 - 19:05:42 EST


From: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
Date: Sat, 1 Sep 2018 20:11:05 +0800

> The kernel module may sleep with holding a spinlock.
>
> The function call paths (from bottom to top) in Linux-4.16 are:
>
> [FUNC] usleep_range
> drivers/net/ethernet/cadence/macb_main.c, 648:
> usleep_range in macb_halt_tx
> drivers/net/ethernet/cadence/macb_main.c, 730:
> macb_halt_tx in macb_tx_error_task
> drivers/net/ethernet/cadence/macb_main.c, 721:
> _raw_spin_lock_irqsave in macb_tx_error_task
>
> To fix this bug, usleep_range() is replaced with udelay().
>
> This bug is found by my static analysis tool DSAC.
>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>

Applied, thanks.