Re: [patch] paravirt: VDSO page is essential

Ingo Molnar
2007-03-06T07:51:26Z

* Zachary Amsden <zach@vmware.com> wrote:

> > yeah. (plus my patches of course that remove the current
> > papering-over hackery and restores COMPAT_VDSO.)
>
> Yes, I don't have a problem with your patch, I just wish I had been
> cc'd on it. [...]

(i Cc:-ed you to the other ones - i simply forgot and bounced it to you
a few hours down the line - sorry!)

> [...] Fixing this is rather tricky, but I believe no strange build
> magic is required, it can be done in kernel init code. Still building
> my SUSE 9.0 guest to test. SUSE 9.0 is one of those that requires
> COMPAT_VDSO, yes?

yeah, and a handful of other ones. It depends on the glibc version:
early vdso glibs were buggy and assumed a few things about the vdso, so
they would segfault on the new-style vdso which is fully relocatable
(and hence mergable into the vma space, randomizable, etc.).

Ingo