From 641f53c07d2760f1a53288c3cab0300030f049cb Mon Sep 17 00:00:00 2001
From: Thierry Reding <treding@nvidia.com>
Date: Mon, 16 Sep 2019 16:19:25 +0200
Subject: drm/nouveau: Fix ordering between TTM and GEM release
Git-commit: 641f53c07d2760f1a53288c3cab0300030f049cb
Patch-mainline: v5.4-rc1
References: bsc#1152472
When the last reference to a TTM BO is dropped, ttm_bo_release() will
acquire the DMA reservation object's wound/wait mutex while trying to
clean up (ttm_bo_cleanup_refs_or_queue() via ttm_bo_release()). It is
therefore essential that drm_gem_object_release() be called after the
TTM BO has been uninitialized, otherwise drm_gem_object_release() has
already destroyed the wound/wait mutex (via dma_resv_fini()).
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
drivers/gpu/drm/nouveau/nouveau_bo.c | 10 ++++++++--
drivers/gpu/drm/nouveau/nouveau_gem.c | 4 ----
2 files changed, 8 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index e7803dca32c5..f8015e0318d7 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -136,10 +136,16 @@ nouveau_bo_del_ttm(struct ttm_buffer_object *bo)
struct drm_device *dev = drm->dev;
struct nouveau_bo *nvbo = nouveau_bo(bo);
- if (unlikely(nvbo->bo.base.filp))
- DRM_ERROR("bo %p still attached to GEM object\n", bo);
WARN_ON(nvbo->pin_refcnt > 0);
nv10_bo_put_tile_region(dev, nvbo->tile, NULL);
+
+ /*
+ * If nouveau_bo_new() allocated this buffer, the GEM object was never
+ * initialized, so don't attempt to release it.
+ */
+ if (bo->base.dev)
+ drm_gem_object_release(&bo->base);
+
kfree(nvbo);
}
diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c
index 1bdffd714456..1324c19f4e5c 100644
--- a/drivers/gpu/drm/nouveau/nouveau_gem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_gem.c
@@ -51,10 +51,6 @@ nouveau_gem_object_del(struct drm_gem_object *gem)
if (gem->import_attach)
drm_prime_gem_destroy(gem, nvbo->bo.sg);
- drm_gem_object_release(gem);
-
- /* reset filp so nouveau_bo_del_ttm() can test for it */
- gem->filp = NULL;
ttm_bo_put(&nvbo->bo);
pm_runtime_mark_last_busy(dev);
--
2.28.0