Bug 729805

Summary:	kernel oops after suspend with active tethering
Product:	[openSUSE] openSUSE 12.1	Reporter:	Juergen Weigert <jw>
Component:	Kernel	Assignee:	Jiri Slaby <jslaby>
Status:	RESOLVED FIXED	QA Contact:	E-mail List <qa-bugs>
Severity:	Normal
Priority:	P5 - None
Version:	Factory
Target Milestone:	---
Hardware:	Other
OS:	Other
Whiteboard:
Found By:	---	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---
Bug Depends on:
Bug Blocks:	357354
Attachments:	screenshot of the panic

Description Juergen Weigert 2011-11-11 09:13:42 UTC

I was using usb tethering, then suspended to ram without disconnecting the tethering.

After resume, kernel sent this line via syslog, every 10 seconds:

 [ 8480.702038] unregister_netdevice: waiting for ppp0 to become free. U

All shells filled up with this, forcing me into a reboot.
during reboot, the system panicked.

Comment 1 Juergen Weigert 2011-11-11 09:22:29 UTC

Created attachment 461625 [details]
screenshot of the panic

Comment 2 Juergen Weigert 2011-11-11 09:31:53 UTC

This happened only once, I cannot reproduce.

Linux d90.suse.de 3.1.0-2-default #1 SMP PREEMPT Thu Nov 3 14:45:45 UTC 2011 (187dde0) i686 i686 i386 GNU/Linux

Comment 3 Jiri Slaby 2012-03-28 08:37:50 UTC

This is perhaps the race which was fixed by:
commit 7fb57a019f94ea0c1290c39b8da753be155af41c
Author: Havard Skinnemoen <hskinnemoen@google.com>
Date:   Wed Nov 30 13:28:14 2011 -0800

    USB: cdc-acm: Fix potential deadlock (lockdep warning)

Is this still reproducible with latest kernel (3.3)?

Comment 4 Jiri Slaby 2012-04-05 09:10:35 UTC

(In reply to comment #2)
> This happened only once, I cannot reproduce.

I see. If that recurs with latest kernels, please reopen.