From: Duoming Zhou duoming@zju.edu.cn
[ Upstream commit 70fae37a09268455b8ab4f64647086b61da6f39c ]
This reverts commit be826ada52f1fcabed5b5217c94609ebf5967211.
The function monitor_card() is a timer handler that runs in an atomic context, but it calls usleep_range() that can sleep. As a result, the sleep-in-atomic-context bugs will happen. The process is shown below:
(atomic context) monitor_card() set_protocol() usleep_range() //sleep
The origin commit c1986ee9bea3 ("[PATCH] New Omnikey Cardman 4000 driver") works fine.
Fixes: be826ada52f1 ("char: pcmcia: cm4000_cs: Replace mdelay with usleep_range in set_protocol") Signed-off-by: Duoming Zhou duoming@zju.edu.cn Link: https://lore.kernel.org/r/20230118141000.5580-1-duoming@zju.edu.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/char/pcmcia/cm4000_cs.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/char/pcmcia/cm4000_cs.c b/drivers/char/pcmcia/cm4000_cs.c index 8f1bce0b4fe50..7057b7bacc8cf 100644 --- a/drivers/char/pcmcia/cm4000_cs.c +++ b/drivers/char/pcmcia/cm4000_cs.c @@ -530,7 +530,8 @@ static int set_protocol(struct cm4000_dev *dev, struct ptsreq *ptsreq) DEBUGP(5, dev, "NumRecBytes is valid\n"); break; } - usleep_range(10000, 11000); + /* can not sleep as this is in atomic context */ + mdelay(10); } if (i == 100) { DEBUGP(5, dev, "Timeout waiting for NumRecBytes getting " @@ -550,7 +551,8 @@ static int set_protocol(struct cm4000_dev *dev, struct ptsreq *ptsreq) } break; } - usleep_range(10000, 11000); + /* can not sleep as this is in atomic context */ + mdelay(10); }
/* check whether it is a short PTS reply? */