Re: [PATCH 3.4 065/125] drm/ttm: Fixed a read/write lock imbalance
From: Thomas Hellstrom
Date: Wed Oct 12 2016 - 09:06:18 EST
IIRC This one goes hand in hand with a vmwgfx (the only user) patch.
Please don't apply until I've figured out whether that patch is also in 3.4.
On 10/12/2016 02:33 PM, lizf@xxxxxxxxxx wrote:
> From: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
> 3.4.113-rc1 review patch. If anyone has any objections, please let me know.
> commit 025af189fb44250206dd8a32fa4a682392af3301 upstream.
> In ttm_write_lock(), the uninterruptible path should call
> __ttm_write_lock() not __ttm_read_lock(). This fixes a vmwgfx hang
> on F23 start up.
> syeh: Extracted this from one of Thomas' internal patches.
> Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
> Reviewed-by: Sinclair Yeh <syeh@xxxxxxxxxx>
> Signed-off-by: Zefan Li <lizefan@xxxxxxxxxx>
> drivers/gpu/drm/ttm/ttm_lock.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
> diff --git a/drivers/gpu/drm/ttm/ttm_lock.c b/drivers/gpu/drm/ttm/ttm_lock.c
> index 075daf4..9934b4d 100644
> --- a/drivers/gpu/drm/ttm/ttm_lock.c
> +++ b/drivers/gpu/drm/ttm/ttm_lock.c
> @@ -180,7 +180,7 @@ int ttm_write_lock(struct ttm_lock *lock, bool interruptible)
> } else
> - wait_event(lock->queue, __ttm_read_lock(lock));
> + wait_event(lock->queue, __ttm_write_lock(lock));
> return ret;