Hello Michal Koutný,
The patch 74e4b956eb1c: "cgroup: Honor caller's cgroup NS when
resolving path" from Aug 26, 2022, leads to the following Smatch
static checker warning:
./include/linux/kernfs.h:600 kernfs_walk_and_get()
warn: sleeping in atomic context
kernel/cgroup/cgroup.c
6639 struct cgroup *cgroup_get_from_path(const char *path)
6640 {
6641 struct kernfs_node *kn;
6642 struct cgroup *cgrp = ERR_PTR(-ENOENT);
6643 struct cgroup *root_cgrp;
6644
6645 spin_lock_irq(&css_set_lock);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
6646 root_cgrp = current_cgns_cgroup_from_root(&cgrp_dfl_root);
6647 kn = kernfs_walk_and_get(root_cgrp->kn, path);
^^^^^^^^^^^^^^^^^^^
The kernfs_walk_and_get() function calls down_read() (a semaphore) so
it can't be called while holding a spinlock.
6648 spin_unlock_irq(&css_set_lock);
6649 if (!kn)
6650 goto out;
regards,
dan carpenter
