This fixes the race between vc4_overflow_mem_work and the init of the job lock. Otherwise we could trigger a NULL pointer dereference during VC4 binding.
Link: https://github.com/anholt/linux/issues/114 Signed-off-by: Stefan Wahren stefan.wahren@i2se.com Fixes: d5b1a78a772f ("drm/vc4: Add support for drawing 3D frames.") --- drivers/gpu/drm/vc4/vc4_gem.c | 1 - drivers/gpu/drm/vc4/vc4_irq.c | 1 + 2 files changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c index d0c6bfb..47d964f 100644 --- a/drivers/gpu/drm/vc4/vc4_gem.c +++ b/drivers/gpu/drm/vc4/vc4_gem.c @@ -1088,7 +1088,6 @@ vc4_gem_init(struct drm_device *dev) INIT_LIST_HEAD(&vc4->render_job_list); INIT_LIST_HEAD(&vc4->job_done_list); INIT_LIST_HEAD(&vc4->seqno_cb_list); - spin_lock_init(&vc4->job_lock);
INIT_WORK(&vc4->hangcheck.reset_work, vc4_reset_work); setup_timer(&vc4->hangcheck.timer, diff --git a/drivers/gpu/drm/vc4/vc4_irq.c b/drivers/gpu/drm/vc4/vc4_irq.c index 7d7af3a..d508d13 100644 --- a/drivers/gpu/drm/vc4/vc4_irq.c +++ b/drivers/gpu/drm/vc4/vc4_irq.c @@ -195,6 +195,7 @@ vc4_irq_preinstall(struct drm_device *dev) struct vc4_dev *vc4 = to_vc4_dev(dev);
init_waitqueue_head(&vc4->job_wait_queue); + spin_lock_init(&vc4->job_lock); INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);
/* Clear any pending interrupts someone might have left around