On Mon, Jun 27, 2016 at 07:08:43PM +0800, kernel test robot wrote: > [ 36.894449] INFO: trying to register non-static key. > [ 36.894450] the code is fine but needs lockdep annotation. > [ 36.894451] turning off the locking correctness validator. > [ 36.894456] CPU: 0 PID: 817 Comm: mount Not tainted > 4.7.0-rc4-00255-g56c8928 #1 > [ 36.894457] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > Debian-1.8.2-1 04/01/2014 > [ 36.894462] 0000000000000000 ffff8800299a3a98 ffffffff81776247 > 0000000000000000 > [ 36.894465] 0000000000000001 ffff8800299a3b00 ffffffff8111ebaa > ffff8800299a3ab8 > [ 36.894469] ffffffff8109b058 00000000299a3ac8 ffffffff81077fe3 > ffff8800299a3ad8 > [ 36.894469] Call Trace: > [ 36.894513] [<ffffffff81776247>] dump_stack+0x82/0xb8 > [ 36.894538] [<ffffffff8111ebaa>] register_lock_class+0x142/0x2f1 > [ 36.894570] [<ffffffff81121bc7>] __lock_acquire+0x15a/0xe6f > [ 36.894606] [<ffffffff81122ca5>] lock_acquire+0x13d/0x1d6 > [ 36.894612] [<ffffffff82eced97>] _raw_spin_lock_irq+0x3f/0x75 > [ 36.894616] [<ffffffff82ecb9d8>] __wait_for_common+0x42/0x148 > [ 36.894620] [<ffffffff82ecbb02>] wait_for_completion+0x24/0x26 > [ 36.894626] [<ffffffff810ff577>] kthread_stop+0x107/0x2a2 > [ 36.894632] [<ffffffff810f972e>] destroy_workqueue+0x14d/0x201
I'm thinking this is the same problem as before; because of the stack being wiped, the lockdep state got trashed and *boom*.
