diff options
| author | Jia-Ju Bai <baijiaju1990@gmail.com> | 2019-12-19 11:34:01 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-28 15:42:18 +0100 |
| commit | 4986129b7013bcec51579163e6cea01a9d57d6c2 (patch) | |
| tree | 9b03f5c0a1fdbb3ba435c39406db2bfe5c26ef05 /drivers/media | |
| parent | fd0faee0f5bc19ac5226f1c3465dd4200311afc2 (diff) | |
media: sti: bdisp: fix a possible sleep-in-atomic-context bug in bdisp_device_run()
[ Upstream commit bb6d42061a05d71dd73f620582d9e09c8fbf7f5b ]
The driver may sleep while holding a spinlock.
The function call path (from bottom to top) in Linux 4.19 is:
drivers/media/platform/sti/bdisp/bdisp-hw.c, 385:
msleep in bdisp_hw_reset
drivers/media/platform/sti/bdisp/bdisp-v4l2.c, 341:
bdisp_hw_reset in bdisp_device_run
drivers/media/platform/sti/bdisp/bdisp-v4l2.c, 317:
_raw_spin_lock_irqsave in bdisp_device_run
To fix this bug, msleep() is replaced with udelay().
This bug is found by a static analysis tool STCheck written by myself.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Fabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/platform/sti/bdisp/bdisp-hw.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/media/platform/sti/bdisp/bdisp-hw.c b/drivers/media/platform/sti/bdisp/bdisp-hw.c index b7892f3efd98..5c4c3f0c57be 100644 --- a/drivers/media/platform/sti/bdisp/bdisp-hw.c +++ b/drivers/media/platform/sti/bdisp/bdisp-hw.c @@ -14,8 +14,8 @@ #define MAX_SRC_WIDTH 2048 /* Reset & boot poll config */ -#define POLL_RST_MAX 50 -#define POLL_RST_DELAY_MS 20 +#define POLL_RST_MAX 500 +#define POLL_RST_DELAY_MS 2 enum bdisp_target_plan { BDISP_RGB, @@ -382,7 +382,7 @@ int bdisp_hw_reset(struct bdisp_dev *bdisp) for (i = 0; i < POLL_RST_MAX; i++) { if (readl(bdisp->regs + BLT_STA1) & BLT_STA1_IDLE) break; - msleep(POLL_RST_DELAY_MS); + udelay(POLL_RST_DELAY_MS * 1000); } if (i == POLL_RST_MAX) dev_err(bdisp->dev, "Reset timeout\n"); |