Bug 66873

Summary:	System freeze on 2.6.8-gentoo-r3, when using tc qdisc.
Product:	Gentoo Linux	Reporter:	Michał Ziąbkowski <mziab>
Component:	[OLD] Core system	Assignee:	Gentoo Kernel Bug Wranglers and Kernel Maintainers <kernel>
Status:	RESOLVED WONTFIX
Severity:	critical	CC:	kernel
Priority:	High
Version:	unspecified
Hardware:	x86
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description Michał Ziąbkowski 2004-10-09 07:30:47 UTC

The discovered bug leads to a complete system freeze when using qdisc. In my case the system freezes when I run tc qdisc add dev ppp0 root tbf rate 190kbit latency 50ms burst 1540. It seems that a memleak is trigged by qdisc. Luckily, I've run into a patch which fixes the problem - http://ck.kolivas.org/patches/2.6/2.6.8.1/2.6.8.1-ck8/split-out/cbq-fixes.diff
I'd suggest it should be added to the default gentoo-dev-sources patchset. Thanks in advance.

Reproducible: Always
Steps to Reproduce:
1. Compile gentoo-dev-sources 2.6.8-r3 with QoS support.
2. Emerge iproute2.
3. Execute tc qdisc add dev ppp0 root tbf rate 190kbit latency 50ms burst 1540 (or any other combination using qdisc)

Actual Results:  
The system totally freezes on the spot or when running an internet app. Sometimes it manages to spit 
out "Kernel panic: Aiee, killing interrupt handler! 
In interrupt handler - not syncing"

Expected Results:  
The command should normally add a new qdisc rule.

Gentoo Base System version 1.4.16
Portage 2.0.50-r11 (default-x86-2004.2, gcc-3.3.4, glibc-2.3.3.20040420-r2, 2.6.8-gentoo-r3)
=================================================================
System uname: 2.6.8-gentoo-r3 i686 AMD Athlon(tm) XP 2000+
Autoconf: sys-devel/autoconf-2.59-r4
Automake: sys-devel/automake-1.8.5-r1
ACCEPT_KEYWORDS="x86"
AUTOCLEAN="yes"
CFLAGS="-O2 -march=athlon-xp -fomit-frame-pointer -pipe"
CHOST="i686-pc-linux-gnu"
COMPILER=""
CONFIG_PROTECT="/etc /usr/X11R6/lib/X11/xkb /usr/kde/2/share/config /usr/kde/3.3/env /usr/kde/3.3/
share/config /usr/kde/3.3/shutdown /usr/kde/3/share/config /usr/share/config /var/qmail/control"
CONFIG_PROTECT_MASK="/etc/gconf /etc/terminfo /etc/env.d"
CXXFLAGS="-O2 -march=athlon-xp -fomit-frame-pointer -pipe"
DISTDIR="/usr/portage/distfiles"
FEATURES="autoaddcvs ccache sandbox"
GENTOO_MIRRORS="http://gentoo.prz.rzeszow.pl"
MAKEOPTS="-j2"
PKGDIR="/usr/portage/packages"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/usr/portage"
PORTDIR_OVERLAY="/home/mziab/ebuild"
SYNC="rsync://rsync3.pl.gentoo.org/gentoo-portage"
USE="3dnow 3dnowex X alsa apm avi berkdb bitmap-fonts cdr crypt cups dvd dvdr encode foomaticdb 
ftp gdbm gif gnome gpm gtk gtk2 imlib joystick jpeg libg++ libwww linguas_pl mad mikmod mmx mmx2 
motif mpeg ncurses nls oggvorbis opengl oss pam pdflib perl png python qt quicktime readline sdl slang 
spell sse ssl tcltk tcpd truetype usb x86 xinerama xml2 xmms xprint xv zlib"

Comment 1 Daniel Drake (RETIRED) gentoo-dev

2004-10-10 14:08:53 UTC

Sorry, even though this seems to have been applied in the 2.6.9 tree, there are too many fixes on top of the one you posted to apply.

So, please just wait until 2.6.9 appears. A gentoo-dev-sources release will follow soon after, and these issues won't exist there.

Thanks for reporting the issue and solution though.