This is a note to let you know that I've just added the patch titled cgroup: set css->id to -1 during init to the 4.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: cgroup-set-css-id-to-1-during-init.patch and it can be found in the queue-4.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 8fa3b8d689a54d6d04ff7803c724fb7aca6ce98e Mon Sep 17 00:00:00 2001 From: Tejun Heo <tj@xxxxxxxxxx> Date: Thu, 26 May 2016 15:42:13 -0400 Subject: cgroup: set css->id to -1 during init From: Tejun Heo <tj@xxxxxxxxxx> commit 8fa3b8d689a54d6d04ff7803c724fb7aca6ce98e upstream. If percpu_ref initialization fails during css_create(), the free path can end up trying to free css->id of zero. As ID 0 is unused, it doesn't cause a critical breakage but it does trigger a warning message. Fix it by setting css->id to -1 from init_and_link_css(). Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Cc: Wenwei Tao <ww.tao0320@xxxxxxxxx> Fixes: 01e586598b22 ("cgroup: release css->id after css_free") Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/cgroup.c | 1 + 1 file changed, 1 insertion(+) --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -5063,6 +5063,7 @@ static void init_and_link_css(struct cgr memset(css, 0, sizeof(*css)); css->cgroup = cgrp; css->ss = ss; + css->id = -1; INIT_LIST_HEAD(&css->sibling); INIT_LIST_HEAD(&css->children); css->serial_nr = css_serial_nr_next++; Patches currently in stable-queue which might be from tj@xxxxxxxxxx are queue-4.6/memcg-css_alloc-should-return-an-err_ptr-value-on-error.patch queue-4.6/memcg-mem_cgroup_migrate-may-be-called-with-irq-disabled.patch queue-4.6/cgroup-disable-irqs-while-holding-css_set_lock.patch queue-4.6/cgroup-set-css-id-to-1-during-init.patch queue-4.6/cgroup-remove-redundant-cleanup-in-css_create.patch queue-4.6/mm-memcontrol-fix-cgroup-creation-failure-after-many-small-jobs.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html