I am trying to track down a problem with linux kernels which hang silently (within 5 minutes or a few hours of boot) if compiled with -march=c3. If I use -march=586mmx or 586 the kernels are stable for days.
As there is nothing in the logs or on a serial console, it is difficult to know where to look for the root of the problem. I would be grateful for some suggestions to start to track this down. I imagine it is a compiler bug or a kernel bug exposed by the march setting. cat /proc/cpuinfo processor : 0 vendor_id : CentaurHauls cpu family : 6 model : 7 model name : VIA Ezra stepping : 10 cpu MHz : 399.000 cache size : 64 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu de tsc msr cx8 mtrr pge mmx 3dnow bogomips : 800.58 clflush size : 32 .. so -march-c3 should be correct, if I understand correctly. An example of the complete command line the compile is using: gcc -m32 -Wp,-MD,drivers/net/.3c59x.o.d -nostdinc -isystem /usr/lib/gcc/i486-linux-gnu/4.1.3/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -Werror-implicit-function-declaration -Os -pipe -msoft-float -mregparm=3 -freg-struct-return -mpreferred-stack-boundary=2 -march=c3 -falign-functions=0 -falign-jumps=0 -falign-loops=0 -mtune=generic -ffreestanding -maccumulate-outgoing-args -Iinclude/asm-i386/mach-default -fomit-frame-pointer -fno-stack-protector -Wdeclaration-after-statement -Wno-pointer-sign -DMODULE -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(3c59x)" -D"KBUILD_MODNAME=KBUILD_STR(3c59x)" -c -o drivers/net/.tmp_3c59x.o drivers/net/3c59x.c I am out of my depth with lots of these, so I would be grateful for advice on whether they are sane! I am using: gcc (GCC) 4.1.3 20070812 (prerelease) (Debian 4.1.2-15) Copyright (C) 2006 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. GNU ld (GNU Binutils for Debian) 2.17.90.20070812 Copyright 2007 Free Software Foundation, Inc. This program is free software; you may redistribute it under the terms of the GNU General Public License version 3 or (at your option) a later version. This program has absolutely no warranty. Thanks for the help, Mark
