diff options
| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2014-08-03 19:59:35 +0900 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2014-09-18 16:39:59 +0200 |
| commit | 1718e957131772d5344ee58e8c804a0641061aff (patch) | |
| tree | a858ab68e253f95ee65256ac5c6113771fd9190b | |
| parent | a84cc78e2adc8e099cd3ef8b0da555df11f25a26 (diff) | |
drm/ttm: Fix possible division by 0 in ttm_dma_pool_shrink_scan().
commit 11e504cc705e8ccb06ac93a276e11b5e8fee4d40 upstream.
list_empty(&_manager->pools) being false before taking _manager->lock
does not guarantee that _manager->npools != 0 after taking _manager->lock
because _manager->npools is updated under _manager->lock.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
| -rw-r--r-- | drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c index 7957beeeaf73..eeb8527aba90 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c @@ -1014,6 +1014,8 @@ ttm_dma_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) return SHRINK_STOP; mutex_lock(&_manager->lock); + if (!_manager->npools) + goto out; pool_offset = pool_offset % _manager->npools; list_for_each_entry(p, &_manager->pools, pools) { unsigned nr_free; @@ -1033,6 +1035,7 @@ ttm_dma_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) p->pool->dev_name, p->pool->name, current->pid, nr_free, shrink_pages); } +out: mutex_unlock(&_manager->lock); return freed; } |