On Tue, 07 Apr 2015, Daniel Vetter daniel@ffwll.ch wrote:

On Fri, Apr 03, 2015 at 10:45:29AM +0300, Tommi Rantala wrote:

...

Regression in commit 2caa80e72b57c6216aec6f6a11fcfb4fec46daa0 Author: Daniel Vetter daniel.vetter@ffwll.ch Date: Sun Feb 22 11:38:36 2015 +0100

drm: Fix deadlock due to getconnector locking changes

If the drm_connector_find() call returns NULL, we should no longer call drm_modeset_unlock() to avoid locking imbalance.

Signed-off-by: Tommi Rantala tt.rantala@gmail.com Cc: Daniel Vetter daniel.vetter@ffwll.ch

Oops, thanks for catching this. If this missed 4.0 then we need to backport it.

Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch

Pushed to topic/drm-fixes, should still make it to 4.0. Thanks for the patch and review.

BR, Jani.

...

---

drivers/gpu/drm/drm_crtc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 679b10e..b6f076b 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -2121,7 +2121,7 @@ int drm_mode_getconnector(struct drm_device *dev, void *data, connector = drm_connector_find(dev, out_resp->connector_id); if (!connector) { ret = -ENOENT;

• goto out;
  

• goto out_unlock;
  

  }

  for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++)

@@ -2201,6 +2201,8 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,

out: drm_modeset_unlock(&dev->mode_config.connection_mutex);

+out_unlock: mutex_unlock(&dev->mode_config.mutex);

return ret;

2.1.0

-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel