Re: [Qemu-devel] [PATCH] PPC: Fix for the gdb single step problem on an rfi instruction

[Sebastian Bauer <mail@sebastianbauer.info>]

Hi!

On Fri, 12 Aug 2011 15:29:58 +0200, Elie Richa wrote:
> I've had this problem recently and your patch does fix the issue, 
> thanks!

I like to bump this as this was not in the latest ppc patch queue. Is 
there anything wrong with that patch?

TIA

Best,
Sebastian

> On 08/10/2011 01:41 PM, Sebastian Bauer wrote:
>> When using gdb to single step a ppc interrupt routine, the execution 
>> flow passes
>> the rfi instruction without actually returning from the interrupt. 
>> The patch
>> fixes this by avoiding to update the nip when the debug exception is 
>> raised
>> and a previous POWERPC_EXCP_SYNC was set. The latter is the case 
>> only, if code for
>> rfi or a related instruction was generated.
>>
>> Signed-off-by: Sebastian Bauer <mail@sebastianbauer.info>
>> ---
>> diff --git a/target-ppc/translate.c b/target-ppc/translate.c
>> index fd7c208..42b91fd 100644
>> --- a/target-ppc/translate.c
>> +++ b/target-ppc/translate.c
>> @@ -287,7 +287,7 @@ static inline void 
>> gen_debug_exception(DisasContext *ctx)
>> {
>> TCGv_i32 t0;
>>
>> - if (ctx->exception != POWERPC_EXCP_BRANCH)
>> + if (ctx->exception != POWERPC_EXCP_BRANCH && ctx->exception != 
>> POWERPC_EXCP_SYNC)
>> gen_update_nip(ctx, ctx->nip);
>> t0 = tcg_const_i32(EXCP_DEBUG);
>> gen_helper_raise_exception(t0);
>>
>>