mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-10-03 23:58:05 +00:00
Code Issues Releases Wiki Activity

dma-buf/sync_file: Increment refcount of fence when all are signaled.

Browse source 
When we merge several fences, if all of them are signaled already, we
still keep one of them. So instead of using add_fence(), which will not
increase the refcount of signaled fences, we should explicitly call
fence_get() for the fence we are keeping.

This patch fixes a kernel panic that can be triggered by creating a fence
that is expired (or increasing the timeline until it expires), then
creating a merged fence out of it, and deleting the merged fence. This
will make the original expired fence's refcount go to zero.

Testcase: igt/sw_sync/sync_expired_merge
Signed-off-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1473966865-4508-1-git-send-email-rafael.antognolli@intel.com
This commit is contained in:
Rafael Antognolli 2016-09-15 12:14:25 -07:00 committed by Sumit Semwal
parent 699fbeeac4
commit 7cec540a72
1 changed files with 2 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
drivers/dma-buf/sync_file.c
View file

@ -253,10 +253,8 @@ static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
for (; i_b < b_num_fences; i_b++)
add_fence(fences, &i, b_fences[i_b]);
if (i == 0) {
add_fence(fences, &i, a_fences[0]);
i++;
}
if (i == 0)
fences[i++] = fence_get(a_fences[0]);
if (num_fences > i) {
nfences = krealloc(fences, i * sizeof(*fences),