Re: [Qemu-devel] [PATCH 4/5 v3][RESEND] ppc: Add software breakpoint support

[Alexander Graf <agraf@suse.de>]

On 24.06.14 15:11, Bharat.Bhushan@freescale.com wrote:
>
>> -----Original Message-----
>> From: Alexander Graf [mailto:agraf@suse.de]
>> Sent: Tuesday, June 24, 2014 6:35 PM
>> To: Bhushan Bharat-R65777
>> Cc: qemu-ppc@nongnu.org; qemu-devel@nongnu.org; maddy@linux.vnet.ibm.com
>> Subject: Re: [PATCH 4/5 v3][RESEND] ppc: Add software breakpoint support
>>
>>
>> On 24.06.14 14:10, Bharat Bhushan wrote:
>>> This patch allow insert/remove software breakpoint
>>>
>>> Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
>>> ---
>>>    target-ppc/kvm.c | 71 +++++++++++++++++++++++++++++++++++++++++++++---------
>> --
>>>    1 file changed, 57 insertions(+), 14 deletions(-)
>>>
>>> diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c index
>>> 5238de7..8e2dbb3 100644
>>> --- a/target-ppc/kvm.c
>>> +++ b/target-ppc/kvm.c
>>> @@ -1317,6 +1317,53 @@ static int kvmppc_handle_dcr_write(CPUPPCState *env,
>> uint32_t dcrn, uint32_t dat
>>>        return 0;
>>>    }
>>>
>>> +int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct
>>> +kvm_sw_breakpoint *bp) {
>>> +    /* Mixed endian case is not handled */
>>> +    uint32_t sc = debug_inst_opcode;
>> What if debug_inst_opcode has never been set (thus is 0)?
> Can "0" be a debug_inst_code ?
>
>> In that case we should fail the insert, no?
> Yes, will checking for "0" is sufficient or we need a cap_ also ?

"0" can be a valid debug_inst_code, but I don't think it's a very smart 
one. Either way works for me.


Alex