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

diff --git a/drivers/gpu/drm/nouveau/core/subdev/instmem/base.c b/drivers/gpu/drm/nouveau/core/subdev/instmem/base.c
index 1188227ca6aa909b88f4912608c97d1b3aa2d186..6565f3dbbe04e7e04c0721ad49f3523688f8b729 100644 (file)
--- 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);