If userspace already dropped its own reference by closing the sw_sync fence fd we might end up in a deadlock where dma_fence_is_signaled_locked() will trigger the release of the fence and thus try to hold the lock to remove the fence from the list. dma_fence_is_signaled_locked() tries to release/free the fence and hold the lock in the process. We fix that by changing the order operation and clean up the list and rb-tree first. v2: Drop fence get/put dance and manipulate the list first (Chris Wilson) Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20170729152217.8362-2-gustavo@padovan.org |
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| .. | ||
| dma-buf.c | ||
| dma-fence-array.c | ||
| dma-fence.c | ||
| Kconfig | ||
| Makefile | ||
| reservation.c | ||
| seqno-fence.c | ||
| sw_sync.c | ||
| sync_debug.c | ||
| sync_debug.h | ||
| sync_file.c | ||
| sync_trace.h | ||