From 956084fc2b910634c7d6422f58137d01c1a39d0e Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 16 Apr 2017 23:17:37 +0900 Subject: [PATCH] Revert "cgroup: avoid attaching a cgroup root to two different superblocks" This reverts commit ebe5ea64e0b5b9526fc66fa712ab5f5ebb5227ef. Andrei reports CRIU test hangs with the patch applied. The bug fixed by the patch isn't too likely to trigger in actual uses. Revert the patch for now. Signed-off-by: Tejun Heo Reported-by: Andrei Vagin Link: http://lkml.kernel.org/r/20170414232737.GC20350@outlook.office365.com --- kernel/cgroup/cgroup-v1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c index 12e19f0636ea8..1dc22f6b49f5e 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -1146,7 +1146,7 @@ struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags, * path is super cold. Let's just sleep a bit and retry. */ pinned_sb = kernfs_pin_sb(root->kf_root, NULL); - if (IS_ERR_OR_NULL(pinned_sb) || + if (IS_ERR(pinned_sb) || !percpu_ref_tryget_live(&root->cgrp.self.refcnt)) { mutex_unlock(&cgroup_mutex); if (!IS_ERR_OR_NULL(pinned_sb)) -- 2.39.5