Re: Linux 2.6.27.27

[Krzysztof Oledzki]

On Mon, 20 Jul 2009, Linus Torvalds wrote:

> On Mon, 20 Jul 2009, Marc Dionne wrote:
> > > Hmm. This sounds more like the binutils bug that people had. Sounds like
> > > an assembler bug if the *.o file ends up being empty or at some fixed
> > > size. If it was cc1 that fails, I'd expect to not see an *.o file at all,
> > > since it didn't generate good assembly.
> > >
> > > In fact, your behavior sounds like the thing that produces the *.o files
> > > core-dumped or died for other reasons, and had a 64kB buffer that either
> > > got flushed or not. That would explain the "zero or exactly 64kB" size.
> > >
> > > It could be ccache too, of course.
> >
> > Actually in my case it turns out that it is ccache after all - if I remove it
> > from the picture everything is fine.  If I re-enable it, even with a clean
> > cache, I get the problem.
> >
> > It might just be a coincidence that it's triggered by the -fwrapv change.
>
> Ok, so this is getting ridiculous. Do we have _three_ different kernel
> issues going on at the same time, all subtly related to tools issues
> rather than the kernel source tree itself?
>
> That's just completely bizarre.
>
> So right now we have:
>
> - Krzysztof Oledzki: the only one who so far has really pinpointed it to
>   the -fwrapv change itself.
>
>   It would be good to really double-check that this is not about ccache,
>   since Marc apparently gets a good kernel without ccache, and -fwrapv
>   seems to be involved.

There is no ccache configured in my systems and the same problem appears 
on a different servers (both i386 and x86-64). However, the configs are 
very similar and the hardware is nearly identical.

I'm pretty sure the only different between bootable and unbootable kernel 
is that fwrapv vs strict-overflow change.

Best regards,

				Krzysztof Olędzki