Re: CVS commit: src/sys/arch

["Cherry G. Mathew" <cherry.g.mathew%gmail.com@localhost>]

On 6 January 2012 20:56, David Holland
<dholland-sourcechanges%netbsd.org@localhost> wrote:
> On Fri, Jan 06, 2012 at 03:15:28PM +0000, Cherry G. Mathew wrote:
>  > Modified Files:
>  >      src/sys/arch/x86/x86: pmap.c
>  >      src/sys/arch/xen/x86: cpu.c
>  >
>  > Log Message:
>  > Address those pesky DIAGNOSTIC messages. \n
>  > Take a performance hit at fork() for not DTRT. \n
>  > Note: Only applicable for kernels built with "options DIAGNOSTIC" \n
>  >
>  > [...]
>  > +#ifdef DIAGNOSTIC
>  > +               pmap_kremove(object, PAGE_SIZE);
>  > +#endif /* DIAGNOSTIC */
>  > [plus two more like that]
>
> Uh... even if that's correct, which doesn't seem too likely on the
> surface of things, it doesn't seem desirable.
>

I agree. The correct fix is to implement pmap_protect() or some such
for kernel entries.

The diagnostic message that it triggers is very verbose for XEN
consoles, which ships with DIAGNOSTIC set by default ( not sure why
this is the case ).

The pmap_kremove()s are harmless, because we know that they're not in
use elsewhere

Cheers,
-- 
~Cherry