drm/nouveau: add locking around instobj list operations

Fixes memory corruptions, oopses, etc. when multiple gpuobjs are
simultaneously created or destroyed.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

1 files changed, 27 insertions, 8 deletions

diff --git a/drivers/gpu/drm/nouveau/core/subdev/instmem/base.c b/drivers/gpu/drm/nouveau/core/subdev/instmem/base.c
index 1188227ca6a..6565f3dbbe0 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/instmem/base.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/instmem/base.c
@@ -40,15 +40,21 @@ nouveau_instobj_create_(struct nouveau_object *parent,
         if (ret)
                 return ret;
 
+        mutex_lock(&imem->base.mutex);
         list_add(&iobj->head, &imem->list);
+        mutex_unlock(&imem->base.mutex);
         return 0;
 }
 
 void
 nouveau_instobj_destroy(struct nouveau_instobj *iobj)
 {
-        if (iobj->head.prev)
-                list_del(&iobj->head);
+        struct nouveau_subdev *subdev = nv_subdev(iobj->base.engine);
+
+        mutex_lock(&subdev->mutex);
+        list_del(&iobj->head);
+        mutex_unlock(&subdev->mutex);
+
         return nouveau_object_destroy(&iobj->base);
 }
 
@@ -88,6 +94,8 @@ nouveau_instmem_init(struct nouveau_instmem *imem)
         if (ret)
                 return ret;
 
+        mutex_lock(&imem->base.mutex);
+
         list_for_each_entry(iobj, &imem->list, head) {
                 if (iobj->suspend) {
                         for (i = 0; i < iobj->size; i += 4)
@@ -97,6 +105,8 @@ nouveau_instmem_init(struct nouveau_instmem *imem)
                 }
         }
 
+        mutex_unlock(&imem->base.mutex);
+
         return 0;
 }
 
@@ -104,17 +114,26 @@ int
 nouveau_instmem_fini(struct nouveau_instmem *imem, bool suspend)
 {
         struct nouveau_instobj *iobj;
-        int i;
+        int i, ret = 0;
 
         if (suspend) {
+                mutex_lock(&imem->base.mutex);
+
                 list_for_each_entry(iobj, &imem->list, head) {
                         iobj->suspend = vmalloc(iobj->size);
-                        if (iobj->suspend) {
-                                for (i = 0; i < iobj->size; i += 4)
-                                        iobj->suspend[i / 4] = nv_ro32(iobj, i);
-                        } else
-                                return -ENOMEM;
+                        if (!iobj->suspend) {
+                                ret = -ENOMEM;
+                                break;
+                        }
+
+                        for (i = 0; i < iobj->size; i += 4)
+                                iobj->suspend[i / 4] = nv_ro32(iobj, i);
                 }
+
+                mutex_unlock(&imem->base.mutex);
+
+                if (ret)
+                        return ret;
         }
 
         return nouveau_subdev_fini(&imem->base, suspend);