diff options
| author | Boris Brezillon <boris.brezillon@collabora.com> | 2019-11-29 14:59:02 +0100 |
|---|---|---|
| committer | Rob Herring <robh@kernel.org> | 2019-12-06 11:05:52 -0600 |
| commit | 70cc77952efebf6722d483cb83cfb563ac9768db (patch) | |
| tree | 168d647aafe7a6c41b948ce3829ad68061a64148 /drivers/gpu | |
| parent | 22bd4df9dadf46f56f2eb16859439a7a600d106a (diff) | |
drm/panfrost: Fix a race in panfrost_ioctl_madvise()
If 2 threads change the MADVISE property of the same BO in parallel we
might end up with an shmem->madv value that's inconsistent with the
presence of the BO in the shrinker list.
The easiest solution to fix that is to protect the
drm_gem_shmem_madvise() call with the shrinker lock.
Fixes: 013b65101315 ("drm/panfrost: Add madvise and shrinker support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191129135908.2439529-3-boris.brezillon@collabora.com
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/panfrost/panfrost_drv.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index 9d086133a84e..8b8d6546cfac 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -347,20 +347,19 @@ static int panfrost_ioctl_madvise(struct drm_device *dev, void *data, return -ENOENT; } + mutex_lock(&pfdev->shrinker_lock); args->retained = drm_gem_shmem_madvise(gem_obj, args->madv); if (args->retained) { struct panfrost_gem_object *bo = to_panfrost_bo(gem_obj); - mutex_lock(&pfdev->shrinker_lock); - if (args->madv == PANFROST_MADV_DONTNEED) - list_add_tail(&bo->base.madv_list, &pfdev->shrinker_list); + list_add_tail(&bo->base.madv_list, + &pfdev->shrinker_list); else if (args->madv == PANFROST_MADV_WILLNEED) list_del_init(&bo->base.madv_list); - - mutex_unlock(&pfdev->shrinker_lock); } + mutex_unlock(&pfdev->shrinker_lock); drm_gem_object_put_unlocked(gem_obj); return 0; |