Re: [Qemu-devel] Support for NetLogic XLP Processors

[Duarte Silva]

On Wednesday 25 March 2015 14:54:41 Leon Alrae wrote:
> On 25/03/2015 14:44, Leon Alrae wrote:
> > Hi Duarte,
> > 
> > On 25/03/2015 14:20, Duarte Silva wrote:
> >> On Wednesday 25 March 2015 13:13:14 James Hogan wrote:
> >>> Hi Duarte,
> >>> 
> >>> On 22/03/15 11:13, Duarte Silva wrote:
> >>>> Hi guys,
> >>>> 
> >>>> I have been struggling to get some binaries compiled for NetLogic XLP
> >>>> processor to run under QEMU. I have tried a bunch of things (most going
> >>>> back and forth) and always get the following error message:
> >>>> 
> >>>> qemu: uncaught target signal 4 (Illegal instruction) - core dumped
> >>>> Illegal instruction
> >>>> 
> >>>> I tried to debug it using GDB but to no avail. Does anybody have ideas?
> >>>> I'm
> >>>> running QEMU 2.2.1.
> >>> 
> >>> It sounds like the program had an instruction that QEMU doesn't
> >>> recognise, or doesn't think should be allowed on the current CPU which
> >>> you've set with -cpu. You might be able to find out what that
> >>> 
> >>> instruction is by putting this on your qemu command line:
> >>>  -singlestep -d in_asm
> >> 
> >> Hi James,
> >> 
> >> thanks for the help :) I have tried with all the CPU's available. None of
> >> them worked, so I just leave it as undefined. It seems the offending
> >> instruction is "udi4".
> >> 
> >> (...)
> >> IN:
> >> 0x765d1fa4:  udi4       a0,v0,zero,0x0
> > 
> > According to this line you are trying to use MIPS32 CPU whereas I
> > presume you would like MIPS64R2? Please try 5KEf CPU for example which
> > is available in qemu-mips64 and qemu-mips64el QEMU binaries for big and
> > little endian respectively.
> 
> I just noticed the QEMU version you are using and it doesn't contain
> 5KEf and 5KEc CPUs. Please try MIPS64R2-generic.
> 
> Leon

Hi Leon,

have a look at the "binary-info.txt" file in the first e-Mail. It does use the 
ELF magic for 32 bits ELF, not the 64 bits, that's why I get the following:

# chroot rootfs/ /usr/local/bin/qemu-mips64 -cpu MIPS64R2-generic /bin/sh
/bin/sh: Invalid ELF image for this architecture

Is there a way to force the execution of the binary even if the flag doesn't 
match?

Also, if you have a look at the flags you get: noreorder, cpic, 32bitmode, 
unknown CPU, o32, mips64r2. So, is it 64 bits or 32 bits ELF file?

Cheers,
Duarte