From 81fcdac0b54488a1fea35a0fe2e799511888fa84 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Mon, 19 Oct 2015 08:44:35 -0700 Subject: [PATCH] drm/vc4: Drop struct_mutex around CL validation. We were using it so that we could make sure that shader validation state didn't change while we were validating, but now shader validation state is immutable. The bcl/rcl generation doesn't do any other BO dereferencing, and seems to have no other global state dependency not covered by job_lock / bo_lock. We only need to hold struct_mutex for object unreferencing. Fixes a lock order reversal between mmap_sem and struct_mutex. Signed-off-by: Eric Anholt --- drivers/gpu/drm/vc4/vc4_gem.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) --- a/drivers/gpu/drm/vc4/vc4_gem.c +++ b/drivers/gpu/drm/vc4/vc4_gem.c @@ -439,10 +439,12 @@ fail: } static void -vc4_complete_exec(struct vc4_exec_info *exec) +vc4_complete_exec(struct drm_device *dev, struct vc4_exec_info *exec) { unsigned i; + /* Need the struct lock for drm_gem_object_unreference(). */ + mutex_lock(&dev->struct_mutex); if (exec->bo) { for (i = 0; i < exec->bo_count; i++) drm_gem_object_unreference(&exec->bo[i].bo->base); @@ -455,6 +457,7 @@ vc4_complete_exec(struct vc4_exec_info * list_del(&bo->unref_head); drm_gem_object_unreference(&bo->base.base); } + mutex_unlock(&dev->struct_mutex); kfree(exec); } @@ -473,7 +476,7 @@ vc4_job_handle_completed(struct vc4_dev list_del(&exec->head); spin_unlock_irqrestore(&vc4->job_lock, irqflags); - vc4_complete_exec(exec); + vc4_complete_exec(vc4->dev, exec); spin_lock_irqsave(&vc4->job_lock, irqflags); } @@ -525,12 +528,8 @@ vc4_job_done_work(struct work_struct *wo { struct vc4_dev *vc4 = container_of(work, struct vc4_dev, job_done_work); - struct drm_device *dev = vc4->dev; - /* Need the struct lock for drm_gem_object_unreference(). */ - mutex_lock(&dev->struct_mutex); vc4_job_handle_completed(vc4); - mutex_unlock(&dev->struct_mutex); } static int @@ -639,7 +638,7 @@ vc4_submit_cl_ioctl(struct drm_device *d return 0; fail: - vc4_complete_exec(exec); + vc4_complete_exec(vc4->dev, exec); return ret; }