FYI, we noticed the below changes on

https://github.com/0day-ci/linux Zhaoyang-Huang/POWER-runtime-refining-the-rpm_suspend-function/20160121-111604
commit dad5d263363749f1dc36854743adb0d1b8f86184 ("POWER/runtime: refining the rpm_suspend function")


+------------------------------------------------------------+------------+------------+
|                                                            | dc7a021ccc | dad5d26336 |
+------------------------------------------------------------+------------+------------+
| boot_successes                                             | 20         | 0          |
| boot_failures                                              | 0          | 7          |
| WARNING:at_kernel/locking/lockdep.c:#lockdep_trace_alloc() | 0          | 7          |
| BUG:kernel_boot_hang                                       | 0          | 1          |
| backtrace:pm_runtime_work                                  | 0          | 7          |
| RIP:csd_lock_wait                                          | 0          | 6          |
| Kernel_panic-not_syncing:softlockup:hung_tasks             | 0          | 6          |
| backtrace:kmem_cache_create                                | 0          | 6          |
| backtrace:usbip_host_init                                  | 0          | 6          |
| backtrace:kernel_init_freeable                             | 0          | 6          |
+------------------------------------------------------------+------------+------------+



[    9.035135] hub 1-0:1.0: USB hub found
[    9.035825] hub 1-0:1.0: 8 ports detected
[    9.038948] ------------[ cut here ]------------
[    9.039645] WARNING: CPU: 1 PID: 33 at kernel/locking/lockdep.c:2755 lockdep_trace_alloc+0x92/0xbe()
[    9.041086] DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
[    9.041708] Modules linked in:
[    9.042543] CPU: 1 PID: 33 Comm: kworker/1:1 Not tainted 4.4.0-03451-gdad5d26 #1
[    9.043616] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
[    9.044892] Workqueue: pm pm_runtime_work
[    9.045606]  0000000000000000 ffff880032097c08 ffffffff8174680d ffff880032097c50
[    9.046929]  ffff880032097c40 ffffffff810de073 ffffffff8111c5a4 0000000000000046
[    9.048257]  00000000024000c0 ffff88001cfc0808 00000000024000c0 ffff880032097ca8
[    9.049575] Call Trace:
[    9.050091]  [<ffffffff8174680d>] dump_stack+0x4b/0x63
[    9.050818]  [<ffffffff810de073>] warn_slowpath_common+0x99/0xb2
[    9.051661]  [<ffffffff8111c5a4>] ? lockdep_trace_alloc+0x92/0xbe
[    9.052481]  [<ffffffff810de0d4>] warn_slowpath_fmt+0x48/0x50
[    9.053291]  [<ffffffff8111c0cb>] ? lock_release+0x1a5/0x41a
[    9.054068]  [<ffffffff8111c5a4>] lockdep_trace_alloc+0x92/0xbe
[    9.054872]  [<ffffffff811f6067>] kmem_cache_alloc_trace+0x36/0x123
[    9.055700]  [<ffffffff81b8f1dc>] rpm_suspend+0x2c/0x18f
[    9.056432]  [<ffffffff81b8f86f>] rpm_idle+0x1c5/0x241
[    9.057147]  [<ffffffff81b90435>] pm_runtime_work+0x5e/0x94
[    9.057904]  [<ffffffff810f3c81>] process_one_work+0x249/0x482
[    9.058692]  [<ffffffff810f43a9>] worker_thread+0x209/0x2c2
[    9.059452]  [<ffffffff810f41a0>] ? rescuer_thread+0x2b3/0x2b3
[    9.060235]  [<ffffffff810f92e5>] kthread+0xc5/0xcd
[    9.060915]  [<ffffffff810f9220>] ? kthread_parkme+0x24/0x24
[    9.061770]  [<ffffffff82e8b8df>] ret_from_fork+0x3f/0x70
[    9.062518]  [<ffffffff810f9220>] ? kthread_parkme+0x24/0x24
[    9.063290] ---[ end trace 94ed5187e23a2b81 ]---
[    9.067333] vhci_hcd: USB/IP 'Virtual' Host Controller (VHCI) Driver v1.0.0





Thanks,
Kernel Test Robot