cgroup: fix bogus kernel warnings when cgroup_create() failed (2739d3cc) · Commits · 戴 / test

If cgroup_create() failed and cgroup_destroy_locked() is called to do cleanup, we'll see a bunch of warnings: cgroup_addrm_files: failed to remove 2MB.limit_in_bytes, err=-2 cgroup_addrm_files: failed to remove 2MB.usage_in_bytes, err=-2 cgroup_addrm_files: failed to remove 2MB.max_usage_in_bytes, err=-2 cgroup_addrm_files: failed to remove 2MB.failcnt, err=-2 cgroup_addrm_files: failed to remove prioidx, err=-2 cgroup_addrm_files: failed to remove ifpriomap, err=-2 ... We failed to remove those files, because cgroup_create() has failed before creating those cgroup files. To fix this, we simply don't warn if cgroup_rm_file() can't find the cft entry. Signed-off-by:

Li Zefan <lizefan@huawei.com> Signed-off-by:

Tejun Heo <tj@kernel.org>

kernel/cgroup.c

+12 −9

Original line number	Diff line number	Diff line
		@@ -921,13 +921,17 @@ static void remove_dir(struct dentry *d)
		dput(parent);
		}

		static int cgroup_rm_file(struct cgroup cgrp, const struct cftype cft)
		static void cgroup_rm_file(struct cgroup cgrp, const struct cftype cft)
		{
		struct cfent *cfe;

		lockdep_assert_held(&cgrp->dentry->d_inode->i_mutex);
		lockdep_assert_held(&cgroup_mutex);

		/*
		* If we're doing cleanup due to failure of cgroup_create(),
		* the corresponding @cfe may not exist.
		*/
		list_for_each_entry(cfe, &cgrp->files, node) {
		struct dentry *d = cfe->dentry;

		@@ -940,9 +944,8 @@ static int cgroup_rm_file(struct cgroup cgrp, const struct cftype cft)
		list_del_init(&cfe->node);
		dput(d);

		return 0;
		break;
		}
		return -ENOENT;
		}

		/**
		@@ -2758,14 +2761,14 @@ static int cgroup_addrm_files(struct cgroup cgrp, struct cgroup_subsys subsys,
		if ((cft->flags & CFTYPE_ONLY_ON_ROOT) && cgrp->parent)
		continue;

		if (is_add)
		if (is_add) {
		err = cgroup_add_file(cgrp, subsys, cft);
		else
		err = cgroup_rm_file(cgrp, cft);
		if (err) {
		pr_warning("cgroup_addrm_files: failed to %s %s, err=%d\n",
		is_add ? "add" : "remove", cft->name, err);
		if (err)
		pr_warn("cgroup_addrm_files: failed to add %s, err=%d\n",
		cft->name, err);
		ret = err;
		} else {
		cgroup_rm_file(cgrp, cft);
		}
		}
		return ret;

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