FYI, we noticed the below changes on

git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
commit 56aa45adcc5b793369e535a4b7177f1c7314b577 ("usb: gadget: make usb functions to load before gadget driver")

This commit fixed an warning as below:

[    8.571726] ------------[ cut here ]------------
[    8.572786] WARNING: at kernel/mutex.c:199 mutex_lock_nested+0x121/0x349()
[    8.572786] Hardware name: Standard PC (i440FX + PIIX, 1996)
[    8.572786] Pid: 1, comm: swapper/0 Not tainted 3.9.0-rc1-00006-gfe2a429 #884
[    8.572786] Call Trace:
[    8.572786]  [<ffffffff81064ed2>] warn_slowpath_common+0x77/0x91
[    8.572786]  [<ffffffff81064fb3>] warn_slowpath_null+0x15/0x17
[    8.572786]  [<ffffffff81b8cbc3>] mutex_lock_nested+0x121/0x349
[    8.572786]  [<ffffffff810106f8>] ? sched_clock+0x9/0xd
[    8.572786]  [<ffffffff8108b161>] ? sched_clock_local+0x11/0x78
[    8.572786]  [<ffffffff81810ffb>] ? gserial_alloc_line+0x2a/0x1c0
[    8.572786]  [<ffffffff81810ffb>] gserial_alloc_line+0x2a/0x1c0
[    8.572786]  [<ffffffff81810ffb>] ? gserial_alloc_line+0x2a/0x1c0
[    8.572786]  [<ffffffff825867f7>] acm_ms_bind+0x2d/0x7ab
[    8.572786]  [<ffffffff81b8da18>] ? mutex_unlock+0x9/0xb
[    8.572786]  [<ffffffff81164e29>] ? sysfs_addrm_finish+0x16/0x52
[    8.572786]  [<ffffffff81163e5d>] ? sysfs_add_file_mode+0xa8/0xdc
[    8.572786]  [<ffffffff81163e9e>] ? sysfs_add_file+0xd/0xf
[    8.572786]  [<ffffffff81163ec3>] ? sysfs_create_file+0x23/0x25
[    8.572786]  [<ffffffff814a9079>] ? device_create_file+0x14/0x16
[    8.572786]  [<ffffffff81806c6e>] ? composite_dev_prepare+0xb0/0xe9
[    8.572786]  [<ffffffff81806e73>] composite_bind+0x9c/0x166
[    8.572786]  [<ffffffff825867b8>] ? m66592_probe+0x418/0x418
[    8.572786]  [<ffffffff8180476f>] udc_bind_to_driver+0x25/0xa6
[    8.572786]  [<ffffffff825867b8>] ? m66592_probe+0x418/0x418
[    8.572786]  [<ffffffff81804dd1>] usb_gadget_probe_driver+0x75/0x88
[    8.572786]  [<ffffffff81806fca>] usb_composite_probe+0x8d/0x8f
[    8.572786]  [<ffffffff825867c8>] init+0x10/0x12
[    8.572786]  [<ffffffff8254ae3e>] do_one_initcall+0x7a/0x13d
[    8.572786]  [<ffffffff8254b079>] kernel_init_freeable+0x178/0x1fb
[    8.572786]  [<ffffffff81b6c473>] ? rest_init+0xb7/0xb7
[    8.572786]  [<ffffffff81b6c47c>] kernel_init+0x9/0xd1
[    8.572786]  [<ffffffff81b910bc>] ret_from_fork+0x7c/0xb0
[    8.572786]  [<ffffffff81b6c473>] ? rest_init+0xb7/0xb7
[    8.572786] ---[ end trace 220a440ac161c663 ]---

Thanks,
Ying Huang