linux/drivers/dma-buf
Christian König 6b51b02a3a dma-buf: fix and rework dma_buf_poll v7
Daniel pointed me towards this function and there are multiple obvious problems
in the implementation.

First of all the retry loop is not working as intended. In general the retry
makes only sense if you grab the reference first and then check the sequence
values.

Then we should always also wait for the exclusive fence.

It's also good practice to keep the reference around when installing callbacks
to fences you don't own.

And last the whole implementation was unnecessary complex and rather hard to
understand which could lead to probably unexpected behavior of the IOCTL.

Fix all this by reworking the implementation from scratch. Dropping the
whole RCU approach and taking the lock instead.

Only mildly tested and needs a thoughtful review of the code.

Pushing through drm-misc-next to avoid merge conflicts and give the code
another round of testing.

v2: fix the reference counting as well
v3: keep the excl fence handling as is for stable
v4: back to testing all fences, drop RCU
v5: handle in and out separately
v6: add missing clear of events
v7: change coding style as suggested by Michel, drop unused variables

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Michel Dänzer <mdaenzer@redhat.com>
CC: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210720131110.88512-1-christian.koenig@amd.com
2021-10-01 09:30:02 +02:00
..
heaps dma-buf: system_heap: Avoid warning on mid-order allocations 2021-09-14 20:25:46 +05:30
dma-buf-sysfs-stats.c dma-buf: Delete the DMA-BUF attachment sysfs statistics 2021-07-20 11:06:59 +02:00
dma-buf-sysfs-stats.h dma-buf: Delete the DMA-BUF attachment sysfs statistics 2021-07-20 11:06:59 +02:00
dma-buf.c dma-buf: fix and rework dma_buf_poll v7 2021-10-01 09:30:02 +02:00
dma-fence-array.c dma-fence: Propagate errors to dma-fence-array container 2019-08-12 08:25:52 +01:00
dma-fence-chain.c dma-buf: some dma_fence_chain improvements 2021-06-14 19:33:16 +02:00
dma-fence.c dma-buf: clarify dma_fence_add_callback documentation 2021-09-03 10:12:12 +02:00
dma-heap.c dma-buf: dma-heap: Provide accessor to get heap name 2021-02-25 18:28:24 +05:30
dma-resv.c dma-resv: Give the docs a do-over 2021-08-30 21:37:59 +02:00
Kconfig dma-buf: DMABUF_SYSFS_STATS should depend on DMA_SHARED_BUFFER 2021-09-07 12:42:21 +05:30
Makefile dma-buf: nuke seqno-fence 2021-08-16 14:07:17 +02:00
selftest.c dma-buf: Introduce selftesting framework 2019-08-19 18:01:34 +01:00
selftest.h dma-buf: Introduce selftesting framework 2019-08-19 18:01:34 +01:00
selftests.h Merge drm/drm-next into drm-intel-next-queued 2020-06-25 18:05:03 +03:00
st-dma-fence-chain.c dma-buf: add dma_fence_chain_alloc/free v3 2021-06-14 19:38:34 +02:00
st-dma-fence.c dma-buf: Avoid comma separated statements 2021-02-09 17:14:11 +01:00
sw_sync.c compat_ioctl: move more drivers to compat_ptr_ioctl 2019-10-23 17:23:44 +02:00
sync_debug.c Linux 5.2-rc5 2019-06-19 12:07:29 +02:00
sync_debug.h
sync_file.c dma-buf/sync_file: Don't leak fences on merge failure 2021-07-12 13:34:49 +02:00
sync_trace.h
udmabuf.c udmabuf: fix general protection fault in udmabuf_create 2021-08-12 09:27:22 +02:00