Re: Kernel compilation failure [SOLVED (probably)]

[Gilles <gilles@harfang.homelinux.org>]

Hello.

> 
> > Obviously, I'm interested in finding out what's wrong with the system.
> > Do you have suggestions as to what I should do to have the kernel provide
> > a little more information in "kern.log"?
> 
> Not sure what to suggest there.  May have to hit lkml for help on this.
>

Well, I compiled a kernel with debugging symbols just to find out that
it wouldn't help in narrowing down the source of the problem. Only that
dreaded "general protection" would appear in the log.

Then browsing the latest kernel changelogs, I stumbled across this (excerpt
from http://www.kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.14-rc2):

 commit bc5e8fdfc622b03acf5ac974a1b8b26da6511c99
 Author: Linus Torvalds <torvalds@g5.osdl.org>
 Date:   Sat Sep 17 15:41:04 2005 -0700

     x86-64/smp: fix random SIGSEGV issues
    
     They seem to have been due to AMD errata 63/122; the fix is to disable
     TLB flush filtering in SMP configurations.
    
     Confirmed to fix the problem by Andrew Walrond <andrew@walrond.org>
    
     [ Let's see if we'll have a better fix eventually, this is the Q&D
       "let's get this fixed and out there" version ]
    
     Signed-off-by: Linus Torvalds <torvalds@osdl.org>


Right now I am in 

 Linux dusk 2.6.14-rc3+patched+g1 #1 SMP Sat Oct 1 14:49:43 CEST 2005 x86_64 GNU/Linux

Well, well, I've just compiled a dozen times...  Without a single failure!
So, a kernel bug it was indeed.


Best regards,
Gilles