On Sat, Jul 29, 2017 at 12:18:32PM -0300, Gustavo Padovan wrote:
Hi Chris,
2017-07-28 Chris Wilson chris@chris-wilson.co.uk:
Up until recently sync_file were create to export a single dma-fence to userspace, and so we could canabalise a bit insie dma-fence to mark whether or not we had enable polling for the sync_file itself. However, with the advent of syncobj, we do allow userspace to create multiple sync_files for a single dma-fence. (Similarly, that the sw-sync validation framework also started returning multiple sync-files wrapping a single dma-fence for a syncpt also triggering the problem.)
This patch reverts my suggestion in commit e24165537312 ("dma-buf/sync_file: only enable fence signalling on poll()") to use a single bit in the shared dma-fence and restores the sync_file->flags for tracking the bits individually.
Reported-by: Gustavo Padovan gustavo@padovan.org Fixes: f1e8c67123cf ("dma-buf/sw-sync: Use an rbtree to sort fences in the timeline") Fixes: e9083420bbac ("drm: introduce sync objects (v4)") Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Cc: Sumit Semwal sumit.semwal@linaro.org Cc: Sean Paul seanpaul@chromium.org Cc: Gustavo Padovan gustavo@padovan.org Cc: dri-devel@lists.freedesktop.org Cc: drm-intel-fixes@lists.freedesktop.org # v4.13-rc1+
drivers/dma-buf/sync_file.c | 5 +++-- include/linux/sync_file.h | 3 ++- 2 files changed, 5 insertions(+), 3 deletions(-)
I confirm the patch fixes the sync kselftests for me. Pushed to drm-misc-next.
You need to cherry-pick this to drm-misc-fixes (using cherry-pick -x to make it clear we applied this twice), since the bug is in 4.13. drm-misc-next is for stuff that's only needed in 4.14. -Daniel