Re: Race condition in module load causing undefined symbols

K.R. Foley
2005-06-14T15:41:05Z

Steve Lord wrote:
> Andrew Morton wrote:
>
>> Stephen Lord <lord@xfs.org> wrote:
>>
>>> Pozsár Balázs wrote:
>>> > On Sat, Jun 11, 2005 at 08:23:20AM -0500, Steve Lord wrote:
>>> > >>I think this is not actually module loading itself, but a problem
>>> >>between the fork/exec/wait code in nash and the kernel.
>>> > > > I do not use nash, only bash, so this is not a nash-specific
>>> issue.
>>> > >
>>> I disabled hyperthreading and things started working, so are there any
>>> HT related scheduling bugs right now?
>>
>>
>>
>> There haven't been any scheduler changes for some time. There have
>> been a
>> few low-level SMT changes I think.
>>
>> Are you able to identify which kernel version broke it?
>>
>
> Still have not narrowed this down too far, disabling SMT made no
> difference, disabling SMP did, which I was expecting.
>
> Steve
>

I initially saw this with 2.6.12-rc1 and every version up through rc3. I
haven't tried with later versions. :-/ I initially reported here:
http://marc.theaimsgroup.com/?l=linux-kernel&m=111235814529008&w=2

The way that I got around it was to compile in my aic7xxx driver instead
of making it a module. I have also recently received an email from
someone saying that disabling module unloading would also solve it. That
very well may be true since I did run into another booting problem
(2.6.12-rc5) that disabling module unloading fixed :-/ I haven't had a
chance to go back and check this out though.

So to summarize: I have a dual 933 with aic7xxx compiled in to get
passed the problem described above. I have a dual 2.6 w/HT that I have
disabled module unloading to get passed another boot condition.

--
kr