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Subject[PATCH 1/2] rtc-r7301: Fix a possible sleep-in-atomic bug in rtc7301_read_time
Date
The driver may sleep under a spinlock.
The function call path is:
rtc7301_read_time (acquire the spinlock)
rtc7301_wait_while_busy
usleep_range --> may sleep

To fix it, usleep_range is replaced with udelay.

This bug is found by my static analysis tool(DSAC) and checked by my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
drivers/rtc/rtc-r7301.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-r7301.c b/drivers/rtc/rtc-r7301.c
index 28d5408..d846e97 100644
--- a/drivers/rtc/rtc-r7301.c
+++ b/drivers/rtc/rtc-r7301.c
@@ -95,7 +95,7 @@ static int rtc7301_wait_while_busy(struct rtc7301_priv *priv)
if (!(val & RTC7301_CONTROL_BUSY))
return 0;

- usleep_range(200, 300);
+ udelay(300);
}

return -ETIMEDOUT;
--
1.7.9.5
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