From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [GIT PULL] cgroup fixes for v4.11-rc6 Date: Mon, 17 Apr 2017 00:33:28 +0900 Message-ID: <20170416153328.GA27786@wtj.duckdns.org> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=UgOkCwNVf7uVxFBAKY6OnQ2jZeVD190czUIHveDCZZM=; b=ko8lAc+zj5MNcjo7Yd7x+xdCd51q+MGyfMFEdhx0UmrDah+gNKJ84gFtidZb8y/P93 ayYvypaZJgEmzh5G05lFHHVnpxKxmB5uXa8Slxb1u7vuNigh6Omvhx+0aWS21QoO5zg1 EZIHZqP5PzO+QBxhJmy1e++yu6vg+VrrBjQy7RQ3GeabKzI8T+noFUBfHNCbmt7DyFJC b9U6+UqIWZhpqEZtjFsFqBlwOm2W98vij+qhDW2BHiEW+Ur17Cr5PJmbQ2Fr4mSHCoDP acmoh2BaDoQjvf6DL4QduB2FWm1/2AZ4Up1C4CyCgqU1gl/R58h/c26+hMzc4HNbMjRT PNIQ== Content-Disposition: inline Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Linus Torvalds Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Li Zefan , Johannes Weiner , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andrei Vagin Hello, Linus. Unfortunately, the commit to fix the cgroup mount race in the previous pull request can lead to hangs. The original bug has been around for a while and isn't too likely to be triggered in usual use cases. Revert the commit for now. Thanks. The following changes since commit bfb0b80db5f9dca5ac0a5fd0edb765ee555e5a8e: cgroup: avoid attaching a cgroup root to two different superblocks (2017-04-11 09:00:57 +0900) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git for-4.11-fixes for you to fetch changes up to 330c418638612d7658b6314e6a244fcb5f7efac5: Revert "cgroup: avoid attaching a cgroup root to two different superblocks" (2017-04-16 23:17:37 +0900) ---------------------------------------------------------------- Tejun Heo (1): Revert "cgroup: avoid attaching a cgroup root to two different superblocks" 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 12e19f0..1dc22f6 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))