Re: [PATCH 3/3] objtool/x86: Fix NOP decode

[Alexandre Chartre]

On 9/25/25 12:42, Peter Zijlstra wrote:
> On Thu, Sep 25, 2025 at 12:03:23PM +0200, Peter Zijlstra wrote:
>
> > > > > >     	case 0x90:
> > > > > > +		if (prefix != 0xf3) /* REP NOP := PAUSE */
> > > > > > +			insn->type = INSN_NOP;
> > > > > >     		break;
>
> > > What about 0x49 0x90, which is xchg (XCHG r8,rAX) ?
>
> I've made that:
>
> 	case 0x90:
> 		if (rex_b) /* XCHG %r8, %rax */
> 			break;
>
> 		if (prefix == 0xf3) /* REP NOP := PAUSE */
> 			break;
>
> 		insn->type = INSN_NOP;
> 		break;

Sounds good.

Reviewed-by: Alexandre Chartre <alexandre.chartre@xxxxxxxxxx>

alex.