I booted a CONFIG_PREEMPT_NONE=y && CONFIG_SMP=n kernel, and got flood of below warning. The location is lockdep_assert_held(&css_set_lock) in cset_cgroup_from_root() in kernel/cgroup.c. linux.git as of 9c982e86dbdb does not hit this warning. [ 2.355852] ------------[ cut here ]------------ [ 2.357417] WARNING: CPU: 0 PID: 59 at kernel/cgroup.c:1159 cset_cgroup_from_root+0x98/0xc0() [ 2.360329] Modules linked in: [ 2.361574] CPU: 0 PID: 59 Comm: kworker/0:2 Not tainted 4.4.0-rc7-next-20151231 #268 [ 2.364241] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013 [ 2.367500] Workqueue: events cgroup_release_agent [ 2.369399] 0000000000000000 0000000006fe97c4 ffff880035adbc90 ffffffff8135125d [ 2.372378] ffff880035adbcc8 ffffffff8105fde6 ffff88007bec4000 ffffffff81c4aae0 [ 2.375042] 0000000000001000 0000000000000000 ffffffff81c3fb40 ffff880035adbcd8 [ 2.377731] Call Trace: [ 2.378775] [<ffffffff8135125d>] dump_stack+0x19/0x1c [ 2.380289] [<ffffffff8105fde6>] warn_slowpath_common+0x76/0xb0 [ 2.382044] [<ffffffff8105ff25>] warn_slowpath_null+0x15/0x20 [ 2.383765] [<ffffffff810d12a8>] cset_cgroup_from_root+0x98/0xc0 [ 2.386169] [<ffffffff810d436a>] cgroup_path+0x4a/0x80 [ 2.388037] [<ffffffff810d4530>] cgroup_release_agent+0xb0/0x110 [ 2.389813] [<ffffffff81078623>] ? process_one_work+0x133/0x400 [ 2.391487] [<ffffffff81078687>] process_one_work+0x197/0x400 [ 2.393163] [<ffffffff81078623>] ? process_one_work+0x133/0x400 [ 2.394942] [<ffffffff81078a14>] worker_thread+0x124/0x490 [ 2.396565] [<ffffffff816a5a82>] ? __schedule+0x2b2/0x880 [ 2.398183] [<ffffffff810788f0>] ? process_one_work+0x400/0x400 [ 2.399942] [<ffffffff8107e308>] kthread+0xf8/0x110 [ 2.401394] [<ffffffff8107e210>] ? kthread_create_on_node+0x220/0x220 [ 2.415321] [<ffffffff816ab2df>] ret_from_fork+0x3f/0x70 [ 2.416921] [<ffffffff8107e210>] ? kthread_create_on_node+0x220/0x220 [ 2.419011] ---[ end trace 4bbece452f458d9b ]--- -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
