[PATCH 1/2] powerpc: Reject probes on instructions that can't be single stepped

[Naveen N. Rao]

Michael Ellerman wrote:
> Murilo Opsfelder Araújo <mopsfelder at gmail.com> writes:
>> On 3/23/22 08:51, Naveen N. Rao wrote:
>>> +static inline bool can_single_step(u32 inst)
>>> +{
>>> +	switch (inst >> 26) {
>> 
>> Can't ppc_inst_primary_opcode() be used instead?

I didn't want to add a dependency on inst.h. But I guess I can very well 
move this out of the header into some .c file. I will see if I can make 
that work.

>>> +	case 31:
>>> +		switch ((inst >> 1) & 0x3ff) {
>>> +		case 4:		/* tw */
>>> +			return false;
>>> +		case 68:	/* td */
>>> +			return false;
>>> +		case 146:	/* mtmsr */
>>> +			return false;
>>> +		case 178:	/* mtmsrd */
>>> +			return false;
>>> +		}
>>> +		break;
>>> +	}
>>> +	return true;
>>> +}
>>> +
>>
>> Can't OP_* definitions from ppc-opcode.h be used for all of these switch-case statements?
> 
> Yes please. And add any that are missing.

We only have OP_31 from the above list now. I'll add the rest.


Thanks,
Naveen