Merge tag 'drm-fixes-2020-03-27' of git://anongit.freedesktop.org/drm/drm

Pull drm fixes from Dave Airlie:
 "Pretty quiet: some minor sg mapping fixes for 3 drivers, and a single
  oops fix for the scheduler. I'm hoping nobody tries to send me a fixes
  pull today but I'll keep an eye out of the weekend.

  radeon/amdgpu/dma-buf:
   - sg list fixes

  scheduler:
   - oops fix"

* tag 'drm-fixes-2020-03-27' of git://anongit.freedesktop.org/drm/drm:
  drm/scheduler: fix rare NULL ptr race
  drm/radeon: fix scatter-gather mapping with user pages
  drm/amdgpu: fix scatter-gather mapping with user pages
  drm/prime: use dma length macro when mapping sg

Author: torvalds

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

@@ -974,7 +974,7 @@ static int amdgpu_ttm_tt_pin_userptr(struct ttm_tt *ttm)
 	/* Map SG to device */
 	r = -ENOMEM;
 	nents = dma_map_sg(adev->dev, ttm->sg->sgl, ttm->sg->nents, direction);
-	if (nents != ttm->sg->nents)
+	if (nents == 0)
 		goto release_sg;
 
 	/* convert SG to linear array of pages and dma addresses */

drivers/gpu/drm/drm_prime.c

@@ -967,7 +967,7 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages,
 
 	index = 0;
 	for_each_sg(sgt->sgl, sg, sgt->nents, count) {
-		len = sg->length;
+		len = sg_dma_len(sg);
 		page = sg_page(sg);
 		addr = sg_dma_address(sg);
 

drivers/gpu/drm/radeon/radeon_ttm.c

@@ -528,7 +528,7 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_tt *ttm)
 
 	r = -ENOMEM;
 	nents = dma_map_sg(rdev->dev, ttm->sg->sgl, ttm->sg->nents, direction);
-	if (nents != ttm->sg->nents)
+	if (nents == 0)
 		goto release_sg;
 
 	drm_prime_sg_to_page_addr_arrays(ttm->sg, ttm->pages,

drivers/gpu/drm/scheduler/sched_main.c

@@ -661,7 +661,9 @@ static void drm_sched_process_job(struct dma_fence *f, struct dma_fence_cb *cb)
 
 	trace_drm_sched_process_job(s_fence);
 
+	dma_fence_get(&s_fence->finished);
 	drm_sched_fence_finished(s_fence);
+	dma_fence_put(&s_fence->finished);
 	wake_up_interruptible(&sched->wake_up_worker);
 }