Re: Fatal Oops on boot with 2.4.0testX and recent GCC snapshots

[Andreas Franck <afranck@gmx.de>]

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The story continues, citing myself:

> Hmm, would have been nice, but it crashes here with 20001222, nevertheless. 
> For which CPU do you have your kernel configured? It might be a CPU 
> specific issue, I'll try to compile for Pentium I and 486, now, and report
> my results.

It does not seem CPU specific, breaks for both 486 and Pentium with the same 
error.

> It would also be nice to know if this is a gcc issue or a kernel issue - if 
> I knew which precise file was responsible for the crash, I could compare 
> the assembly output for stable and snapshot GCC. My suspect is
> kernel/sched.c, but this might be wrong, as the story begins on the launch 
> of kupdate in fs/buffer.c.

And this is where everything seems to go wrong: When I compile buffer.c with 
2.95.2, and link everything together, the kernel magically boots without any 
complaints; later on something starts crashing badly, but this might be other 
issues that can be investigated later on.

> But now I have almost no clue what really goes wrong
... and now I have a bit more, and the suspection that something broke the 
way in which the kernel_thread function (arch/i386/kernel/process.c) wants to 
start the kernel threads, here bdflush and kupdate. I don't understand all 
issues completely, but something seems to have changed.

Attached are the relevant (?) portions of the assembly output for buffer.c: 
kupdate, bdflush and bdflush_init, compiled with 2.95.2 and 2.97, 
respectively. Perhaps someone could look over it?

Thanks and happy hacking,
Andreas

-- 
->>>----------------------- Andreas Franck --------<<<-
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