[PATCH 2/2] bdisp: Fix a possible sleep-in-atomic bug in bdisp_hw_save_request

From: Jia-Ju Bai
Date: Tue Dec 12 2017 - 08:45:37 EST


The driver may sleep under a spinlock.
The function call path is:
bdisp_device_run (acquire the spinlock)
bdisp_hw_update
bdisp_hw_save_request
devm_kzalloc(GFP_KERNEL) --> may sleep

To fix it, GFP_KERNEL is replaced with GFP_ATOMIC.

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

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
---
drivers/media/platform/sti/bdisp/bdisp-hw.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/platform/sti/bdisp/bdisp-hw.c b/drivers/media/platform/sti/bdisp/bdisp-hw.c
index 4b62ceb..7b45b43 100644
--- a/drivers/media/platform/sti/bdisp/bdisp-hw.c
+++ b/drivers/media/platform/sti/bdisp/bdisp-hw.c
@@ -1064,7 +1064,7 @@ static void bdisp_hw_save_request(struct bdisp_ctx *ctx)
if (!copy_node[i]) {
copy_node[i] = devm_kzalloc(ctx->bdisp_dev->dev,
sizeof(*copy_node[i]),
- GFP_KERNEL);
+ GFP_ATOMIC);
if (!copy_node[i])
return;
}
--
1.7.9.5