Revert "char: pcmcia: cm4000_cs: Replace mdelay with usleep_range in set_protocol"
authorDuoming Zhou <duoming@zju.edu.cn>
Wed, 18 Jan 2023 14:10:00 +0000 (22:10 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 10 Mar 2023 08:39:38 +0000 (09:39 +0100)
[ 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

index 8f1bce0b4fe503652779089e3709c2e15a619af5..7057b7bacc8cf8654ea4aefff9f24d5c8fa2dd4b 100644 (file)
@@ -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? */