From 16fe10cf92783ed9ceb182d6ea2b8adf5e8ec1b8 Mon Sep 17 00:00:00 2001 From: Jia-Ju Bai <baijiaju1990@gmail.com> Date: Sat, 1 Sep 2018 20:11:05 +0800 Subject: [PATCH] net: cadence: Fix a sleep-in-atomic-context bug in macb_halt_tx() 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@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- drivers/net/ethernet/cadence/macb_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index c6707ea2d7519..16e4ef7d71855 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -649,7 +649,7 @@ static int macb_halt_tx(struct macb *bp) if (!(status & MACB_BIT(TGO))) return 0; - usleep_range(10, 250); + udelay(250); } while (time_before(halt_time, timeout)); return -ETIMEDOUT; -- 2.30.2