Re: [PATCH] Gerd Hoffman's move-vsyscall-into-user-address-range patch

Linus Torvalds
2006-05-20T01:15:27Z

On Fri, 19 May 2006, Andrew Morton wrote:
> >
> > FC1 is like really ancient. I think there was a glibc bug that caused
> > vsyscall related init hangs like that. To nevertheless let people run
> > their old stuff there's a vdso=0 boot option in exec-shield.
>
>
> Well that patch took a machine from working to non-working. Pretty serious
> stuff. We should get to the bottom of the problem so we can assess the
> risk and impact, no?

Yes. And it would be good to have a way to turn it off - either globally
of by some per-process setup (eg off by default, but turn on when doing
some magic).

The per-process one would be the harder one, because it would require the
fixmap entry, but not globally. So I suspect the only practical thing
would be to have it be a kernel boot-time option.

Linus