Re: RT patch breaks X86_64 build

[Ingo Molnar <mingo@elte.hu>]

* Michal Schmidt <xschmi00@stud.feec.vutbr.cz> wrote:

> Ingo Molnar wrote:
> >hm, one difference is that i'm running a 64-bit kernel but 32-bit 
> >userspace (FC3-ish).
> 
> Yes, that's it! I've just successfully booted into 32-bit userspace (I 
> have a separate partition with old 32-bit Debian) with x86_64 kernel and 
> LATENCY_TRACE enabled. Everything seemed to work.
> Then I mounted my normal root partition under /mnt/64 and tried
>   chroot /mnt/64
> I got a SIGSEGV. Then I copied some simple binaries from /mnt/64/bin to 
> /root/test/bin and some necessary libraries to /root/test/lib and did
>   chroot /root/test
> I could run 64-bit sash, ls, cat, date, mkdir - it worked. 64-bit bash 
> however segfaulted.

perhaps my mcount stubs dont save enough registers, leading to register 
corruption on 64-bit userspace? In that case i'd expect more breakage 
though, so maybe it's something more subtle.

	Ingo