[PATCH] drm/radeon: signal all fences after lockup to avoid endless waiting in GEM_WAIT

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

After a lockup, fences are not signalled sometimes, causing
the GEM_WAIT_IDLE ioctl to never return, which sometimes results
in an X server freeze.

This fixes only one of many deadlocks which can occur during a lockup.

Signed-off-by: Marek Olšák <marek.olsak at amd.com>
---
 drivers/gpu/drm/radeon/radeon_device.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index 841d0e0..7b97baa 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -1552,6 +1552,11 @@ int radeon_gpu_reset(struct radeon_device *rdev)
 	radeon_save_bios_scratch_regs(rdev);
 	/* block TTM */
 	resched = ttm_bo_lock_delayed_workqueue(&rdev->mman.bdev);
+
+	mutex_lock(&rdev->ring_lock);
+	radeon_fence_driver_force_completion(rdev);
+	mutex_unlock(&rdev->ring_lock);
+
 	radeon_pm_suspend(rdev);
 	radeon_suspend(rdev);
 
-- 
1.8.1.2