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| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-12-04 21:48:18 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-12-06 10:22:55 +0100 |
| commit | a703c55004e1c5076d57e43771b3e11117796ea0 (patch) | |
| tree | 2be0916f74fc5e69786a4347e19f0d793cbf4309 /include | |
| parent | ae64f9bd1d3621b5e60d7363bc20afb46aede215 (diff) | |
| download | linux-a703c55004e1c5076d57e43771b3e11117796ea0.tar.bz2 | |
drm: safely free connectors from connector_iter
In
commit 613051dac40da1751ab269572766d3348d45a197
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Wed Dec 14 00:08:06 2016 +0100
drm: locking&new iterators for connector_list
we've went to extreme lengths to make sure connector iterations works
in any context, without introducing any additional locking context.
This worked, except for a small fumble in the implementation:
When we actually race with a concurrent connector unplug event, and
our temporary connector reference turns out to be the final one, then
everything breaks: We call the connector release function from
whatever context we happen to be in, which can be an irq/atomic
context. And connector freeing grabs all kinds of locks and stuff.
Fix this by creating a specially safe put function for connetor_iter,
which (in this rare case) punts the cleanup to a worker.
Reported-by: Ben Widawsky <ben@bwidawsk.net>
Cc: Ben Widawsky <ben@bwidawsk.net>
Fixes: 613051dac40d ("drm: locking&new iterators for connector_list")
Cc: Dave Airlie <airlied@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: <stable@vger.kernel.org> # v4.11+
Reviewed-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171204204818.24745-1-daniel.vetter@ffwll.ch
Diffstat (limited to 'include')
| -rw-r--r-- | include/drm/drm_connector.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h index df9807a3caae..a4649c56ca2f 100644 --- a/include/drm/drm_connector.h +++ b/include/drm/drm_connector.h @@ -916,6 +916,14 @@ struct drm_connector { uint8_t num_h_tile, num_v_tile; uint8_t tile_h_loc, tile_v_loc; uint16_t tile_h_size, tile_v_size; + + /** + * @free_work: + * + * Work used only by &drm_connector_iter to be able to clean up a + * connector from any context. + */ + struct work_struct free_work; }; #define obj_to_connector(x) container_of(x, struct drm_connector, base) |