Re: [2.4 patch] fix CONFIG_X86_L1_CACHE_SHIFT

[Andi Kleen <ak@suse.de>]

peter_daum@t-online.de (Peter Daum) writes:

> ... actually, the problems also occurred when running on machines
> with Pentium II/Pentium Pro CPUs - even on these machines, I only
> could use kernels compiled with "CONFIG_MPENTIUM4".
> 
> Adrian's patch does fix these problems. What is amazing, is that
> in kernel version 2.4.20, the same values were used for
> "CONFIG_X86_L1_CACHE_SHIFT". The problems that I described,
> however, occur only with 2.4.22 - the same machines with the same
> configuration work just fine with 2.4.20. Maybe, there's
> something else involved, too?

Yes it very much sounds like some memory corruption that is just
masked by the bigger cacheline padding.

Maybe you should try to compile with CONFIG_DEBUG_SLAB on 
and see if it triggers something?

The padding itself is a pure optimization, if it changes any behaviour
that's a bug.

-Andi