Re: bio linked list corruption.

From: Dave Jones
Date: Thu Oct 20 2016 - 18:50:44 EST


On Tue, Oct 18, 2016 at 06:05:57PM -0700, Andy Lutomirski wrote:

> One possible debugging approach would be to change:
>
> #define NR_CACHED_STACKS 2
>
> to
>
> #define NR_CACHED_STACKS 0
>
> in kernel/fork.c and to set CONFIG_DEBUG_PAGEALLOC=y. The latter will
> force an immediate TLB flush after vfree.

I can give that idea some runtime, but it sounds like this a case where
we're trying to prove a negative, and that'll just run and run ? In which case I
might do this when I'm travelling on Sunday.

> Also, CONFIG_DEBUG_VIRTUAL=y can be quite helpful for debugging stack
> issues. I'm tempted to do something equivalent to hardwiring that
> option on for a while if CONFIG_VMAP_STACK=y.

This one I had on. Nothing interesting jumped out.

Dave