[Intel-gfx] [PATCH] drm/i915: drop the struct_mutex when wedged or trying to reset

[Matthew Auld]

We grab the struct_mutex in intel_crtc_page_flip, but if we are wedged
or a reset is in progress we bail early but never seem to actually
release the lock.

Fixes: 7f1847ebf48b ("drm/i915: Simplify checking of GPU reset_counter in display pageflips")
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Matthew Auld <matthew.auld at intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 5d11002319f7..772a72a21513 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12214,7 +12214,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
 	intel_crtc->reset_count = i915_reset_count(&dev_priv->gpu_error);
 	if (i915_reset_in_progress_or_wedged(&dev_priv->gpu_error)) {
 		ret = -EIO;
-		goto cleanup;
+		goto unlock;
 	}
 
 	atomic_inc(&intel_crtc->unpin_work_count);
@@ -12302,6 +12302,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
 	intel_unpin_fb_obj(fb, crtc->primary->state->rotation);
 cleanup_pending:
 	atomic_dec(&intel_crtc->unpin_work_count);
+unlock:
 	mutex_unlock(&dev->struct_mutex);
 cleanup:
 	crtc->primary->fb = old_fb;
-- 
2.9.3