lkml.org 
[lkml]   [2019]   [Apr]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.18 13/50] android: unconditionally remove callbacks in sync_fence_free()
Date
3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 699f685569434510d944e419f4048c4e3ba8d631 ]

Using fence->status to determine whether or not there are callbacks
remaining on the sync_fence is racy since fence->status may have been
decremented to 0 on another CPU before fence_check_cb_func() has
completed. By unconditionally calling fence_remove_callback() for each
fence in the sync_fence, we guarantee that each callback has either
completed (since fence_remove_callback() grabs the fence lock) or been
removed.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/staging/android/sync.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c
index f83e00c78051..50a9945da27e 100644
--- a/drivers/staging/android/sync.c
+++ b/drivers/staging/android/sync.c
@@ -519,12 +519,10 @@ static const struct fence_ops android_fence_ops = {
static void sync_fence_free(struct kref *kref)
{
struct sync_fence *fence = container_of(kref, struct sync_fence, kref);
- int i, status = atomic_read(&fence->status);
+ int i;

for (i = 0; i < fence->num_fences; ++i) {
- if (status)
- fence_remove_callback(fence->cbs[i].sync_pt,
- &fence->cbs[i].cb);
+ fence_remove_callback(fence->cbs[i].sync_pt, &fence->cbs[i].cb);
fence_put(fence->cbs[i].sync_pt);
}

--
2.19.1


\
 
 \ /
  Last update: 2019-04-01 19:40    [W:0.177 / U:0.924 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site