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Subject[PATCH] drm: Fix a possible sleep-in-atomic bug in show_leaks
Date
The driver may sleep under a spinlock.
The function call path is:
drm_vma_offset_manager_destroy (acquire the spinlock)
drm_mm_takedown
show_leaks
kmalloc(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@gmail.com>
---
drivers/gpu/drm/drm_mm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index 61a1c8e..5b9965d 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -127,7 +127,7 @@ static void show_leaks(struct drm_mm *mm)
unsigned long entries[STACKDEPTH];
char *buf;

- buf = kmalloc(BUFSZ, GFP_KERNEL);
+ buf = kmalloc(BUFSZ, GFP_ATOMIC);
if (!buf)
return;

--
1.7.9.5
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