From: David Yang Date: Thu, 11 Jun 2026 07:08:51 +0000 (+0800) Subject: devlink: Warn on resource ID collision with PARENT_TOP X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f1e13d23e0c8ff5fcbde34c079fbc015475fc3f5;p=thirdparty%2Fkernel%2Flinux.git devlink: Warn on resource ID collision with PARENT_TOP ID 0 serves as the sentinel DEVLINK_RESOURCE_ID_PARENT_TOP to mark top-level resources. While it is technically possible to use 0 as a real resource ID, a user might be tempted to write: enum { MY_RESOURCE_ID_A, /* == DEVLINK_RESOURCE_ID_PARENT_TOP ! */ MY_RESOURCE_ID_B, MY_RESOURCE_ID_C, MY_RESOURCE_ID_D, ... }; register(..., MY_RESOURCE_ID_C, DEVLINK_RESOURCE_ID_PARENT_TOP, ...); register(..., MY_RESOURCE_ID_D, MY_RESOURCE_ID_C, ...); /* D is a child of C */ register(..., MY_RESOURCE_ID_A, DEVLINK_RESOURCE_ID_PARENT_TOP, ...); register(..., MY_RESOURCE_ID_B, MY_RESOURCE_ID_A, ...); /* Is B intentionally top-level, or is it actually a child of A? */ Add a WARN_ON() to catch this and prevent confusion. Signed-off-by: David Yang Link: https://patch.msgid.link/20260611070856.889700-6-mmyangfl@gmail.com Signed-off-by: Jakub Kicinski --- diff --git a/net/devlink/resource.c b/net/devlink/resource.c index 3d2f42bc2fb5f..574108ccfe5d2 100644 --- a/net/devlink/resource.c +++ b/net/devlink/resource.c @@ -486,6 +486,8 @@ __devl_resource_register(struct devlink *devlink, struct list_head *resource_list; bool top_hierarchy; + WARN_ON(resource_id == DEVLINK_RESOURCE_ID_PARENT_TOP); + lockdep_assert_held(&devlink->lock); top_hierarchy = parent_resource_id == DEVLINK_RESOURCE_ID_PARENT_TOP;