Re: Bug creating USB endpoints in 2.6.20.x (kernel bug 8198)

--- Alan Stern <[email protected]> wrote:
> However it is usually the same endpoint number and the same device (even 
> if the device number changes)?  In that case we can tell the code where to 
> look for errors, because we will always know when that particular endpoint 
> file is created and when it is destroyed.

I think it's safe to say "yes, it's always ep84" here, provided I am trying to provoke the bug
with winecfg. I have obviously seen this bug in a few other scenarios as well over the months,
e.g. from the report in bugzilla:

BUG: unable to handle kernel paging request at virtual address 6b6b6d6b
printing eip:
c0130113
*pde = 00000000
Oops: 0002 [#1]
PREEMPT SMP
last sysfs file: /class/net/eth2/statistics/collisions
...
CPU: 1
EIP: 0060:[<c0130113>] Not tainted VLI
EFLAGS: 00010202 (2.6.20.1 #3)
EIP is at module_put+0x20/0x52
eax: 6b6b6d6b ebx: 6b6b6b6b ecx: 00000001 edx: e0049000
esi: f60f7b08 edi: 6b6b6b6b ebp: ebc14e0c esp: e0049f58
ds: 007b es: 007b ss: 0068
Process udevd (pid: 7608, ti=e0049000 task=f7e6b030 task.ti=e0049000)
Stack: f7898edc c0183a5b 00000010 ed5bbb7c eccd0978 c0151253 00000000 00000000
f7ff2208 ed5bbb7c f75b5360 00000000 ed5bbb7c c014ed90 00000003 00000003
f75b5360 f75b53e0 c014fd89 00000003 00000007 00000003 e0049000 c0102bce
Call Trace:
[<c0183a5b>] sysfs_release+0x2d/0x4c
[<c0151253>] __fput+0x96/0x13c
[<c014ed90>] filp_close+0x51/0x58
[<c014fd89>] sys_close+0x70/0xa7
[<c0102bce>] sysenter_past_esp+0x5f/0x85
[<c0270033>] __sched_text_start+0x6b3/0x965
=======================
Code: 00 89 f0 83 c4 0c 5b 5e 5f 5d c3 53 89 c3 85 c0 74 49 b8 01 00 00 00 e8 5f
49 fe ff e8 3b 5b
07 00 c1 e0 07 8d 84 18 80 01 00 00 <ff> 08 83 3b 02 75 0b 8b 83 88 05 00 00 e8
a9 45 fe ff b8 01
00
EIP: [<c0130113>] module_put+0x20/0x52 SS:ESP 0068:e0049f58
<6>note: udevd[7608] exited with preempt_count 1
BUG: scheduling while atomic: udevd/0x10000001/7608
[<c026f9d6>] __sched_text_start+0x56/0x965
[<c011cc72>] irq_exit+0x37/0x42
[<c010d1d7>] smp_apic_timer_interrupt+0x70/0x79
[<c010369c>] apic_timer_interrupt+0x28/0x30
[<c0114b01>] __cond_resched+0x12/0x2c
[<c02708e9>] cond_resched+0x26/0x31
[<c01404d2>] unmap_vmas+0x3d3/0x4df
[<c0142cf5>] exit_mmap+0x7e/0x10a
[<c0116bd7>] mmput+0x1d/0x78
[<c011b322>] do_exit+0x1b2/0x6d8
[<c011007b>] sys_vm86+0x99/0x21d
[<c01040fc>] die+0x1f7/0x21c
[<c011180e>] do_page_fault+0x442/0x510
[<c01113cc>] do_page_fault+0x0/0x510
[<c027230c>] error_code+0x7c/0x84
[<c0130113>] module_put+0x20/0x52
[<c0183a5b>] sysfs_release+0x2d/0x4c
[<c0151253>] __fput+0x96/0x13c
[<c014ed90>] filp_close+0x51/0x58
[<c014fd89>] sys_close+0x70/0xa7
[<c0102bce>] sysenter_past_esp+0x5f/0x85
[<c0270033>] __sched_text_start+0x6b3/0x965
=======================

However, I have been able to configure my way around these other scenarios.

Does anyone have access to a machine with 2 or more logical CPUs? That does seem to be a common
feature among the few people who do encounter this bug.

Cheers,
Chris



		
___________________________________________________________ 
Copy addresses and emails from any email account to Yahoo! Mail - quick, easy and free. http://uk.docs.yahoo.com/trueswitch2.html

-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take
control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel