linux-stable.git/drivers/dma-buf, branch linux-5.14.y

dma-buf: WARN on dmabuf release with pending attachments

2021-11-17T10:03:43+00:00

[ Upstream commit f492283b157053e9555787262f058ae33096f568 ]

It is expected from the clients to follow the below steps on an imported
dmabuf fd:
a) dmabuf = dma_buf_get(fd) // Get the dmabuf from fd
b) dma_buf_attach(dmabuf); // Clients attach to the dmabuf
   o Here the kernel does some slab allocations, say for
dma_buf_attachment and may be some other slab allocation in the
dmabuf->ops->attach().
c) Client may need to do dma_buf_map_attachment().
d) Accordingly dma_buf_unmap_attachment() should be called.
e) dma_buf_detach () // Clients detach to the dmabuf.
   o Here the slab allocations made in b) are freed.
f) dma_buf_put(dmabuf) // Can free the dmabuf if it is the last
reference.

Now say an erroneous client failed at step c) above thus it directly
called dma_buf_put(), step f) above. Considering that it may be the last
reference to the dmabuf, buffer will be freed with pending attachments
left to the dmabuf which can show up as the 'memory leak'. This should
at least be reported as the WARN().

Signed-off-by: Charan Teja Reddy 
Reviewed-by: Christian König 
Link: https://patchwork.freedesktop.org/patch/msgid/1627043468-16381-1-git-send-email-charante@codeaurora.org
Signed-off-by: Christian König 
Signed-off-by: Sasha Levin

dma-buf: DMABUF_DEBUG should depend on DMA_SHARED_BUFFER

2021-09-26T12:10:19+00:00

[ Upstream commit cca62758ebdd71fcfb6d589d6487a7f26398d50d ]

DMA-BUF debug checks are an option of DMA-BUF.  Enabling DMABUF_DEBUG
without DMA_SHARED_BUFFER does not have any impact, as drivers/dma-buf/
is not entered during the build when DMA_SHARED_BUFFER is disabled.

Fixes: 84335675f2223cbd ("dma-buf: Add debug option")
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Sumit Semwal 
Link: https://patchwork.freedesktop.org/patch/msgid/20210902124913.2698760-3-geert@linux-m68k.org
Signed-off-by: Sasha Levin

dma-buf: DMABUF_MOVE_NOTIFY should depend on DMA_SHARED_BUFFER

2021-09-26T12:10:19+00:00

[ Upstream commit c4f3a3460a5daebc772d9263500e4099b11e7300 ]

Move notify between drivers is an option of DMA-BUF.  Enabling
DMABUF_MOVE_NOTIFY without DMA_SHARED_BUFFER does not have any impact,
as drivers/dma-buf/ is not entered during the build when
DMA_SHARED_BUFFER is disabled.

Fixes: bb42df4662a44765 ("dma-buf: add dynamic DMA-buf handling v15")
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210902124913.2698760-2-geert@linux-m68k.org
Signed-off-by: Sasha Levin

dma-buf: fix dma_resv_test_signaled test_all handling v2

2021-09-18T11:43:35+00:00

[ Upstream commit 9d38814d1e346ea37a51cbf31f4424c9d059459e ]

As the name implies if testing all fences is requested we
should indeed test all fences and not skip the exclusive
one because we see shared ones.

v2: fix logic once more

Signed-off-by: Christian König 
Reviewed-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210702111642.17259-3-christian.koenig@amd.com
Signed-off-by: Sasha Levin

Merge tag 'drm-misc-fixes-2021-07-13' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

2021-07-13T13:15:17+00:00

Short summary of fixes pull:

 * dma-buf: Fix fence leak in sync_file_merge() error code
 * drm/panel: nt35510: Don't fail on DSI reads

Signed-off-by: Daniel Vetter 
From: Thomas Zimmermann 
Link: https://patchwork.freedesktop.org/patch/msgid/YO07pEfweKVO+7y0@linux-uq9g

dma-buf/sync_file: Don't leak fences on merge failure

2021-07-12T11:34:49+00:00

Each add_fence() call does a dma_fence_get() on the relevant fence.  In
the error path, we weren't calling dma_fence_put() so all those fences
got leaked.  Also, in the krealloc_array failure case, we weren't
freeing the fences array.  Instead, ensure that i and fences are always
zero-initialized and dma_fence_put() all the fences and kfree(fences) on
every error path.

Signed-off-by: Jason Ekstrand 
Reviewed-by: Christian König 
Fixes: a02b9dc90d84 ("dma-buf/sync_file: refactor fence storage in struct sync_file")
Cc: Gustavo Padovan 
Cc: Christian König 
Link: https://patchwork.freedesktop.org/patch/msgid/20210624174732.1754546-1-jason@jlekstrand.net
Signed-off-by: Christian König

dma-buf: drop the _rcu postfix on function names v3

2021-06-06T09:19:51+00:00

The functions can be called both in _rcu context as well
as while holding the lock.

v2: add some kerneldoc as suggested by Daniel
v3: fix indentation

Signed-off-by: Christian König 
Reviewed-by: Jason Ekstrand 
Acked-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-7-christian.koenig@amd.com

dma-buf: rename and cleanup dma_resv_get_list v2

2021-06-06T09:18:19+00:00

When the comment needs to state explicitly that this is doesn't get a reference
to the object then the function is named rather badly.

Rename the function and use it in even more places.

v2: use dma_resv_shared_list as new name

Signed-off-by: Christian König 
Acked-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-5-christian.koenig@amd.com

dma-buf: rename and cleanup dma_resv_get_excl v3

2021-06-06T09:17:58+00:00

When the comment needs to state explicitly that this
doesn't get a reference to the object then the function
is named rather badly.

Rename the function and use rcu_dereference_check(), this
way it can be used from both rcu as well as lock protected
critical sections.

v2: improve kerneldoc as suggested by Daniel
v3: use dma_resv_excl_fence as function name

Signed-off-by: Christian König 
Acked-by: Daniel Vetter 
Reviewed-by: Jason Ekstrand 
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-4-christian.koenig@amd.com

dma-buf: add missing EXPORT_SYMBOL

2021-06-05T11:08:57+00:00

The newly added dma_resv_reset_shared_max() is used from an inline
function, so it can appear in drivers as well.

Signed-off-by: Christian König 
Acked-by: Alex Deucher 
Reviewed-by: Jason Ekstrand 
Link: https://patchwork.freedesktop.org/patch/msgid/20210604155228.616679-1-christian.koenig@amd.com