Re: [discuss] booting a kernel compiled with -mregparm=0

[Andi Kleen <ak@muc.de>]

Tigran Aivazian <tigran@veritas.com> writes:
>
> When I said "2-3 weeks of work" I didn't fully realize the complexity
> of the problem. It is actually more like several months of research
> work and then (most likely) coming to the conclusion that the code to
> simulate the cpu (by disassembling the functions to track down where
> those registers went in each function) is just too complex to be
> written.

Did you actually ever read the ABI? 

The ABI supported way is to read the DWARF2 unwind tables. For that
you would a dwarf2 reader.  gdb does that in user space, and libgcc2
also does it for exception unwinding. IA64 has an in kernel dwarf2
reader library (and ia64 kdb uses it), although it would probably need
some work to make it work on x86-64.

So far nobody wanted it enough to do the porting work though.


-Andi