On 2021/5/8 15:34, Pierre Moreau wrote:

Hello Zhen,

There was a similar patch sent in last month, though which does not seem to have been merged yet; see https://lists.freedesktop.org/archives/nouveau/2021-April/038451.html.

Whether `ret` should be `-ENOSPC` or `-ENOMEM` is hard to say as `nouveau_get_backlight_name()` could fail due to either.

I will propose an alternative fix which modifies `nouveau_get_backlight_name()` to return an int so the actual error code can be propagated back instead of guessed, as well as fix an ida ID leak which I just spotted.

It's a good idea.

Best, Pierre

On 2021-05-08 — 11:48, Zhen Lei wrote:

...

Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function.

Fixes: db1a0ae21461 ("drm/nouveau/bl: Assign different names to interfaces") Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: Zhen Lei thunder.leizhen@huawei.com

---

drivers/gpu/drm/nouveau/nouveau_backlight.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c index 72f35a2babcb..097ca344a086 100644 --- a/drivers/gpu/drm/nouveau/nouveau_backlight.c +++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c @@ -273,6 +273,7 @@ nouveau_backlight_init(struct drm_connector *connector) return -ENOMEM;

if (!nouveau_get_backlight_name(backlight_name, bl)) {

• ret = -ENOSPC;
  

  NV_ERROR(drm, "Failed to retrieve a unique name for the backlight interface\n"); goto fail_alloc; }

-- 2.25.1

.