Bug 20671 – general protection faults at boot with gentoo-sources-2.4.20-r4 on some athlon processors

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Derek Dolney 2003-05-09 00:21:48 UTC]

There is a bug in one of the patches included with gentoo-sources-2.4.20-r4 that
makes the kernel unbootable for some athlon processors.

The bug is in the patch file 902_minor_fixes. At the very end (line 34) there is
a section that reads:

--- linux-2.4.20-pfeifer-r1_pre8/arch/i386/kernel/setup.c       2003-05-03
09:26:13.000000000 -0500
+++ linux-2.4.20-pfeifer-r1_pre9/arch/i386/kernel/setup.c       2003-05-03
15:17:14.000000000 -0500
@@ -1426,11 +1426,11 @@
                case 6: /* An Athlon/Duron */
                                                                                
                        /* Bit 15 of Athlon specific MSR 15, needs to be 0
-                        * to enable SSE on Palomino/Morgan CPU's.
+                        * to enable SSE on Palomino/Morgan/Thoroughbred CPU's.
                         * If the BIOS didn't enable it already, enable it
                         * here.
                         */
-                       if (c->x86_model == 6 || c->x86_model == 7) {
+                       if (c->x86_model >= 6 || c->x86_model <= 8) {
                                if (!test_bit(X86_FEATURE_XMM,
                                              &c->x86_capability)) {
                                        printk(KERN_INFO

The last line changed by this patch gives a condition that is always true! I
imagine what is intended is:

+                       if (c->x86_model >= 6 && c->x86_model <= 8) {

Reproducible: Always
Steps to Reproduce:
1.
2.
3.




Portage 2.0.47-r10 (default-x86-1.4, gcc-3.2.2, glibc-2.3.1-r4)
=================================================================
System uname: 2.4.20-gentoo-r3 i686 AMD Athlon(tm) Processor
GENTOO_MIRRORS=" ftp://ftp.gtlib.cc.gatech.edu/pub/gentoo
ftp://ftp.ussg.iu.edu/pub/linux/gentoo
http://194.83.57.2/sites/www.ibiblio.org/gentoo/"
CONFIG_PROTECT="/etc /var/qmail/control /usr/share/config
/usr/kde/2/share/config /usr/kde/3/share/config /usr/X11R6/lib/X11/xkb
/usr/share/texmf/tex/generic/config/ /usr/share/texmf/tex/platex/config/"
CONFIG_PROTECT_MASK="/etc/gconf /etc/env.d"
PORTDIR="/usr/portage"
DISTDIR="/usr/portage/distfiles"
PKGDIR="/usr/portage/packages"
PORTAGE_TMPDIR="/var/tmp"
PORTDIR_OVERLAY=""
USE="directfb slang aalib nas ggi guile perl python -arts -avi -berkdb -cups
-encode -esd -imlib -kde -libg++ -libwww -mikmod -motif -nls -oggvorbis -oss
-pam -qt -sdl -svga -tcpd -xmms x86 3dnow alsa apm bonobo crypt emacs gdbm gif
gnome gpm gtk gtk2 java jpeg maildir mmx mozilla mpeg ncurses opengl pdflib png
quicktime readline spell ssl tcltk tetex truetype usb X xml2 xv zlib"
COMPILER="gcc3"
CHOST="i686-pc-linux-gnu"
CFLAGS="-march=athlon-tbird -O3 -fomit-frame-pointer -pipe"
CXXFLAGS="-march=athlon-tbird -O3 -fomit-frame-pointer -pipe"
ACCEPT_KEYWORDS="x86 ~x86"
MAKEOPTS="-j2"
AUTOCLEAN="yes"
SYNC="rsync://rsync.gentoo.org/gentoo-portage"
FEATURES="sandbox ccache userpriv usersandbox"

[Comment 1 Jay Pfeifer (RETIRED) 2003-05-09 00:31:12 UTC]

yep, this is an error. i'll fix and upload the updated tarball.

Thanks,

Jay

[Comment 2 Jay Pfeifer (RETIRED) 2003-05-09 00:40:16 UTC]

this is now in portage. updated md5sums:
MD5 c439d5c93d7fc9a1480a90842465bb97 linux-2.4.20.tar.bz2 27421046
MD5 2a4c5baeff092fb2cc78c9a5ed0d7f9a patches-2.4.20-gentoo-r4.tar.bz2 4142712

Thanks again,

Jay

[Comment 3 Matt Taylor 2003-05-09 13:22:29 UTC]

wouldn't you want to include model 10 also as per bug 20173 to include the Bartons?

[Comment 4 Jay Pfeifer (RETIRED) 2003-05-09 22:43:26 UTC]

barton is now added. i'm bumping to 2.4.20-r5 (i'm bundling it now) as the upstream had a few typos in the crypto docs also wanted to fix a USAGI issue.

Thanks,

Jay