Re: usb: warning in vhci_hcd_probe/lockdep_init_map

[Shuah Khan]

On 12/02/2016 09:09 AM, Andrey Konovalov wrote:
> On Fri, Dec 2, 2016 at 4:58 PM, Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>> On Fri, Dec 02, 2016 at 03:35:44PM +0100, Andrey Konovalov wrote:
>>> Hi!
>>>
>>> I've got the following error report while booting the kernel with
>>> various usb configs enabled.
>>
>> Any hint as to what these "various usb configs" are?
> 
> Hi Greg,
> 
> Here's my .config:
> https://gist.github.com/xairy/46bc7495dfa7d78701d937af81db0175
> 
> Thanks for looking at this!
> 
>>
>>> On commit 2caceb3294a78c389b462e7e236a4e744a53a474 (Dec 1).

Looks like the above commit at the latest on Linus's master
that is do with

ovl: fix d_real() for stacked fs

Nothing jumped out at me from the log. What's your ability to
bisect the problem?

>>>
>>> gadgetfs: USB Gadget filesystem, version 24 Aug 2004
>>> usbip_core: USB/IP Core v1.0.0
>>> vhci_hcd vhci_hcd: USB/IP Virtual Host Controller
>>> vhci_hcd vhci_hcd: new USB bus registered, assigned bus number 2
>>> BUG: key ffff88006a7e8d18 not in .data!
>>> ------------[ cut here ]------------
>>> WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:3131
>>> lockdep_init_map+0x60c/0x770
>>> DEBUG_LOCKS_WARN_ON(1)[    1.567044] Modules linked in:
>>> CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.9.0-rc7+ #58
>>> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
>>>  ffff88006bce6eb8 ffffffff81f96c8a ffffffff00000a02 1ffff1000d79cd6a
>>>  ffffed000d79cd62 000000046bce6ed8 0000000041b58ab3 ffffffff8598af40
>>>  ffffffff81f969f8 0000000000000000 0000000041b58ab3 0000000000000200
>>> Call Trace:
>>>  [<     inline     >] __dump_stack lib/dump_stack.c:15
>>>  [<ffffffff81f96c8a>] dump_stack+0x292/0x398 lib/dump_stack.c:51
>>>  [<ffffffff812b808f>] __warn+0x19f/0x1e0 kernel/panic.c:550
>>>  [<ffffffff812b8195>] warn_slowpath_fmt+0xc5/0x110 kernel/panic.c:565
>>>  [<ffffffff813f3efc>] lockdep_init_map+0x60c/0x770 kernel/locking/lockdep.c:3131
>>>  [<ffffffff819e43d4>] __kernfs_create_file+0x114/0x2a0 fs/kernfs/file.c:954
>>>  [<ffffffff819e68f5>] sysfs_add_file_mode_ns+0x225/0x520 fs/sysfs/file.c:305
>>>  [<     inline     >] create_files fs/sysfs/group.c:64
>>>  [<ffffffff819e8a89>] internal_create_group+0x239/0x8f0 fs/sysfs/group.c:134
>>>  [<ffffffff819e915f>] sysfs_create_group+0x1f/0x30 fs/sysfs/group.c:156
>>>  [<ffffffff8323de24>] vhci_start+0x5b4/0x7a0 drivers/usb/usbip/vhci_hcd.c:978
>>>  [<ffffffff82c907ca>] usb_add_hcd+0x8da/0x1c60 drivers/usb/core/hcd.c:2867
>>>  [<ffffffff8323bc57>] vhci_hcd_probe+0x97/0x130 drivers/usb/usbip/vhci_hcd.c:1103
>>>  [<ffffffff827484ca>] platform_drv_probe+0x8a/0x180 drivers/base/platform.c:568
>>>  [<     inline     >] really_probe drivers/base/dd.c:375
>>>  [<ffffffff82741db4>] driver_probe_device+0x514/0x980 drivers/base/dd.c:515
>>>  [<ffffffff8274260b>] __device_attach_driver+0x22b/0x290 drivers/base/dd.c:610
>>>  [<ffffffff8273b3bc>] bus_for_each_drv+0x15c/0x200 drivers/base/bus.c:463
>>>  [<ffffffff827415c6>] __device_attach+0x266/0x3c0 drivers/base/dd.c:667
>>>  [<ffffffff8274270a>] device_initial_probe+0x1a/0x20 drivers/base/dd.c:714
>>>  [<ffffffff8273ec06>] bus_probe_device+0x1e6/0x290 drivers/base/bus.c:557
>>>  [<ffffffff82738266>] device_add+0xd06/0x1660 drivers/base/core.c:1136
>>>  [<ffffffff82747f55>] platform_device_add+0x315/0x660 drivers/base/platform.c:408
>>>  [<ffffffff82749ba6>] platform_device_register_full+0x396/0x4b0 drivers/base/platform.c:540
>>>  [<     inline     >] platform_device_register_resndata ./include/linux/platform_device.h:111
>>>  [<     inline     >] platform_device_register_simple ./include/linux/platform_device.h:140
>>>  [<     inline     >] add_platform_device drivers/usb/usbip/vhci_hcd.c:1213
>>>  [<ffffffff864e87aa>] vhci_hcd_init+0x215/0x305 drivers/usb/usbip/vhci_hcd.c:1254
>>>  [<ffffffff81000696>] do_one_initcall+0xf6/0x360 init/main.c:778
>>>  [<     inline     >] do_initcall_level init/main.c:844
>>>  [<     inline     >] do_initcalls init/main.c:852
>>>  [<     inline     >] do_basic_setup init/main.c:870
>>>  [<ffffffff86424f84>] kernel_init_freeable+0x5c7/0x6a1 init/main.c:1017
>>>  [<ffffffff84f2b7d3>] kernel_init+0x13/0x180 init/main.c:943
>>>  [<ffffffff84f44f2a>] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:433
>>> ---[ end trace c33c7b202cf3aac8 ]---
>>
>> Odd, I don't see anything strange here.  Shuah, any ideas what is going
>> wrong here?

I will take a look at this. Nothing jumped out at me.

>>
>> thanks,
>>
>> greg k-h
> 
> 

thanks,
-- Shuah