4.9-stable review patch. If anyone has any objections, please let me know.
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From: Dominik Behr dbehr@chromium.org
commit ea4d5a270b57fa8d4871f372ca9b97b7697fdfda upstream.
To avoid hanging userspace components that might have been waiting on the active fences of the destroyed timeline we need to signal with error all remaining fences on such timeline.
This restore the default behaviour of the Android sw_sync framework, which Android still relies on. It was broken on the dma fence conversion a few years ago and never fixed.
v2: Do not bother with cleanup do the list (Chris Wilson)
Reviewed-by: Chris Wilson chris@chris-wilson.co.uk Signed-off-by: Dominik Behr dbehr@chromium.org Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.com Link: https://patchwork.freedesktop.org/patch/msgid/20170907190246.16425-2-gustavo... [s/dma_fence/fence/g - gregkh] Cc: Jisheng Zhang Jisheng.Zhang@synaptics.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/dma-buf/sw_sync.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
--- a/drivers/dma-buf/sw_sync.c +++ b/drivers/dma-buf/sw_sync.c @@ -321,8 +321,16 @@ static int sw_sync_debugfs_open(struct i static int sw_sync_debugfs_release(struct inode *inode, struct file *file) { struct sync_timeline *obj = file->private_data; + struct sync_pt *pt, *next;
- smp_wmb(); + spin_lock_irq(&obj->lock); + + list_for_each_entry_safe(pt, next, &obj->pt_list, link) { + fence_set_error(&pt->base, -ENOENT); + fence_signal_locked(&pt->base); + } + + spin_unlock_irq(&obj->lock);
sync_timeline_put(obj); return 0;