Bug 162574

Summary:	net-dialup/ltmodem causes kernel panic when dialing
Product:	Gentoo Linux	Reporter:	Serhiy Kalchuk <skalchuk>
Component:	Current packages	Assignee:	Gentoo Dialup Developers <net-dialup>
Status:	VERIFIED CANTFIX
Severity:	critical
Priority:	High
Version:	unspecified
Hardware:	x86
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---
Attachments:	Kernel panic full output

Description Serhiy Kalchuk 2007-01-17 19:56:42 UTC

When I dial to my ISP (with wvdial) everything goes fine until the moment when connection should be established. Then I get a message:

BUG: unable to handle kernel paging request at virtual address ffffffc5
<... some very hard to understand debug and backtrace info ...>
<0> Kernel panic - not syncing: Fatal exception in interrupt.

The problem appeared when I switched to gentoo-sources-2.6.18-r6 and added several new options in config in comparison to my previous 2.6.17-r8 one like HPET timer support, Local APIC support for uniprocessors and Use register arguments. Disabling them resolves the problem. However, I didn't figure out yet which feature listed above exactly causes it.


Reproducible: Always

Steps to Reproduce:

Comment 1 Jakub Moc (RETIRED) gentoo-dev

2007-01-17 20:54:50 UTC

<... some very hard to understand debug and backtrace info ...>

Might be hard to understand, but you need to post it; we can't guess... Also try with 2.6.19-r4.

Comment 2 Serhiy Kalchuk 2007-01-23 21:19:00 UTC

I tried it with 2.6.19-r4 using the config with HPET,Local APIC and register arguments options but it failed too. See the attached picture of the full output.

There also appeared a new line (the very last one), which repeats constantly.

Comment 3 Serhiy Kalchuk 2007-01-23 21:23:08 UTC

Created attachment 107950 [details]
Kernel panic full output

Comment 4 Jakub Moc (RETIRED) gentoo-dev

2007-01-23 21:28:35 UTC

Noone will notice again if you don't reopen...

Comment 5 Serhiy Kalchuk 2007-01-24 08:12:53 UTC

Oops.. =) Thanks! Actually, that's my first bug report, so I don't really know what to do when.

Comment 6 Alin Năstac (RETIRED) gentoo-dev

2007-03-17 08:27:26 UTC

Is your modem actually supported by ltmodem? Did you tried with slmodem or hsfmodem? You should use scanModem utility found at http://linmodems.technion.ac.il/#scanModem to see what package support your specific modem (if any).

I'm sorry, but the kernel modules installed these packages are not open source and therefore we can't do much more than redirect you to one of these alternatives.

Closed as CANTFIX.

Comment 7 Serhiy Kalchuk 2007-03-17 13:54:56 UTC

(In reply to comment #6)
The modem works fine unless my kernel is compiled with 'use registered arguments' option (REGPARM).