On 2025/1/3 02:17, Fan Ni wrote: >> - >> static bool is_idle(struct device *dev, struct nd_namespace_common *ndns) >> { >> struct nd_region *nd_region = to_nd_region(dev->parent); >> @@ -168,7 +161,7 @@ ssize_t nd_namespace_store(struct device *dev, >> goto out; >> } >> >> - found = device_find_child(dev->parent, name, namespace_match); >> + found = device_find_child_by_name(dev->parent, name); > Looks good to me. > Just one general question. > The function device_find_child checks parent and parent->p, but > device_find_child_by_name only checks parent although they share the > code except the match function. Why that? > Thank you Fan for code review. I did not touch device_find_child_by_name() parameter checking at that time. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=903c44939abc02e2f3d6f2ad65fa090f7e5df5b6 since [PATCH v5 05/12] will come finally. https://lore.kernel.org/all/20241224-const_dfc_done-v5-5-6623037414d4@xxxxxxxxxxx/ > Fan