Re: [OpenBIOS] Ppc guest debugging?

[Jd Lyons]

> On Oct 11, 2018, at 12:57 PM, Mark Cave-Ayland  wrote:
>
> On 11/10/2018 12:12, Jd Lyons via OpenBIOS wrote:
> > > > > I installed gdb-multiarch and started qemu with:
> > > > >
> > > > > Qemu-system-ppc -s -S
> > > > >
> > > > > The launched gdb-multiarch and connected  to port 1234.
> > > > >
> > > > > Is this the correct toolchain for debugging PPC code on an X86 host, or do I need to do something else?
>
> I actually build gdb from source for the architectures I need (sparc32, sparc64 and
> ppc), so I can't really comment on how multi-arch works.

Can I build gdb for debugging ppc code on x86?

Any instructions on how to do that?

Or should I be using a PPC host for this?
> > > > I used Apple's PowerPC gdb.
>
> Note that Apple have patched their gdb quite heavily, for example I couldn't even
> build it on Linux. On the plus side if you are able to do this, Apple's gdb is at
> least able to read symbols from Mach binaries.
> > > My host system is X86, I was thinking Mark, or someone here once outlined a way to debug Openbios by installing some sort of  powerpc debug tools on X86?
> >
> > Ok, breakpoint not working with gdb-multiarch:
> >
> > (gdb)target remote localhost:1234
> > (gdb)break CalcRAMSize
> > (gdb)continue
> >
> > It just boots the Mac OS and only waits before continue.
> >
> > I'm sure I'm doing something wrong here, maybe I need some PPC Libs installed, my host is X86?
>
> I normally allow gdb to detect correct arch before attaching to the remote with
> "target remote ..." by passing a relevant ELF file to gdb e.g.
>
> power-linux-gdb openbios-ppc
>
> Note that symbols such as CalcRAMSize are generally only visible in the guest, so
> you'll either need to take the executable from the guest and generate a gdb symbol
> file for it, or otherwise use breakpoints for routines based upon their address e.g.
>
> break *0x12345678
>
> ATB,
>
> Mark.