Re: [PATCH] Mutilated form of Andi Kleen's AMD prefetch errata patch

Andrew Morton
2003-10-01T06:59:18Z

Andi Kleen <ak@suse.de> wrote:
>
> Andrew Morton <akpm@osdl.org> writes:
>
> > Looking at Andi's patch, it is also a dead box if the fault happens inside
> > down_write(mmap_sem). That should be fixed, methinks.
>
> The only way to fix all that would be to move the instruction checks early
> into the fast path.

Well the deadlock avoidance only needs to happen if the fault occured in
kernel mode. Presumably most faults are in userspace, so most of the
overhead can be avoided.