[Bug 31219] Re: USB stack dies when I disconnect my mobile phone's USB cable

[Matt Thrailkill]

Actually my old comment is wrong, this only happens when I unplug my
phone.  I emailed my dmesg to a Redhat kernel dev I know, and this is
what he said:

> Here is a copy of what is in /var/log/syslog when I unplug my phone from
> my laptop w/ the latest ubuntu kernel.

> Jun 26 01:55:04 localhost kernel: [17180317.156000] kernel BUG at kernel/workqueue.c:109!
> Jun 26 01:55:04 localhost kernel: [17180317.156000] invalid operand: 0000 [#1]
> Jun 26 01:55:04 localhost kernel: [17180317.156000] PREEMPT SMP
> Jun 26 01:55:04 localhost kernel: [17180317.156000] EFLAGS: 00010202   (2.6.15-25-686)
> Jun 26 01:55:04 localhost kernel: [17180317.156000]  [pg0+434898390/1069184000] usb_serial_disconnect+0x56/0xd0 [usbserial]

It's only going to be fixed months from now, I'm afraid. My patch is
only going to be complete in 2.6.18 pre, and when Ubuntu picks it is
anyone's guess.

-- Pete

He also said this:

> Here is a copy of what is in /var/log/syslog when I unplug my phone from
> my laptop w/ the latest ubuntu kernel.

I knew about it before. Here's what Linus accepted already:

http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=2f8ad9a1b91bc6856860a2fea8b07e0c82c0ad0a

Unfortunately, it's not complete, there's a follow-up patch queued:

http://ftp.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/gregkh-04-usb
/usb-fix-usb-serial-leaks-oopses-on-disconnect.patch

BTW, it's not cdc-acm. Note that usb_serial_disconnect was in the
traceback.

-- Pete


2.6.18-rc1 came out recently, I hope someone can backport the fix (if it
exists) from there into the current Ubuntu kernels.  Otherwise, every
time I unplug my phone I have to reboot to dial out with it or connect
any other usb device again.

-- 
USB stack dies when I disconnect my mobile phone's USB cable
https://launchpad.net/bugs/31219