On Sun, Apr 06, 2025 at 09:43:02PM +0100, Tingmao Wang wrote:
> +struct v9fs_ino_path *make_ino_path(struct dentry *dentry)
> +{
> + struct v9fs_ino_path *path;
> + size_t path_components = 0;
> + struct dentry *curr = dentry;
> + ssize_t i;
> +
> + lockdep_assert_held_read(&v9fs_dentry2v9ses(dentry)->rename_sem);
> +
> + rcu_read_lock();
> +
> + /* Don't include the root dentry */
> + while (curr->d_parent != curr) {
> + path_components++;
> + curr = curr->d_parent;
> + }
> + if (WARN_ON(path_components > SSIZE_MAX)) {
> + rcu_read_unlock();
> + return NULL;
> + }
> +
> + path = kmalloc(struct_size(path, names, path_components),
> + GFP_KERNEL);
Blocking allocation under rcu_read_lock().
