[PATCH net-next v2 5/5] devlink: Warn on resource ID collision with PARENT_TOP
From: David Yang <mmyangfl@gmail.com>
Date: 2026-06-11 07:09:49
Also in:
lkml
Subsystem:
devlink, networking [general], the rest · Maintainers:
Jiri Pirko, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 <mmyangfl@gmail.com>
---
net/devlink/resource.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/devlink/resource.c b/net/devlink/resource.c
index 3d2f42bc2fb5..574108ccfe5d 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;
--
2.53.0