From 330c418638612d7658b6314e6a244fcb5f7efac5 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 bfb0b80db5f9dca5ac0a5fd0edb765ee555e5a8e. 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 12e19f0636ea..1dc22f6b49f5 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)) -- 2.20.1