Re: [PATCH 1/2] linux-user/ppc: deliver SIGTRAP on POWERPC_EXCP_TRAP

[Matheus K. Ferst]

On 03/01/2022 14:50, Richard Henderson wrote:
> On 1/3/22 8:56 AM, matheus.ferst@eldorado.org.br wrote:
> > From: Matheus Ferst <matheus.ferst@eldorado.org.br>
> >
> > Handle POWERPC_EXCP_TRAP in cpu_loop to deliver SIGTRAP on tw[i]/td[i].
> > The si_code comes from do_program_check in the kernel source file
> > arch/powerpc/kernel/traps.c
> >
> > Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
> > ---
> >   linux-user/ppc/cpu_loop.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/linux-user/ppc/cpu_loop.c b/linux-user/ppc/cpu_loop.c
> > index 30c82f2354..8fbaa772dc 100644
> > --- a/linux-user/ppc/cpu_loop.c
> > +++ b/linux-user/ppc/cpu_loop.c
> > @@ -242,7 +242,9 @@ void cpu_loop(CPUPPCState *env)
> >                   }
> >                   break;
> >               case POWERPC_EXCP_TRAP:
> > -                cpu_abort(cs, "Tried to call a TRAP\n");
> > +                info.si_signo = TARGET_SIGTRAP;
> > +                info.si_errno = 0;
> > +                info.si_code = TARGET_TRAP_BRKPT;
>
> You're missing the address, which should be nip.
>
> https://github.com/torvalds/linux/blob/master/arch/powerpc/kernel/traps.c#L1503 

After this switch-case, there is a

info._sifields._sigfault._addr = env->nip;

Is there anything else to be set?

> Please use force_sig_fault.  (I have a pending patch set to convert all 
> other instances;
> hopefully that can be merged soon...)

I'll send v2 with a Based-on

Thanks,
Matheus K. Ferst
Instituto de Pesquisas ELDORADO <http://www.eldorado.org.br/>
Analista de Software
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