Re: [PATCH v2 3/3] objtool: Support stack-swizzle

[Peter Zijlstra <peterz@infradead.org>]

On Tue, Feb 09, 2021 at 10:16:03AM +0100, Peter Zijlstra wrote:
> @@ -2193,6 +2232,12 @@ static int update_cfi_state(struct instr
>  			/* mov reg, disp(%rsp) */
>  			save_reg(cfi, op->src.reg, CFI_CFA,
>  				 op->dest.offset - cfi->stack_size);
> +
> +		} else if (op->src.reg == CFI_SP && op->dest.offset == 0) {
> +
> +			/* mov %rsp, (%reg); # setup a stack swizzle. */
> +			cfi->vals[op->dest.reg].base = CFI_SP_INDIRECT;
> +			cfi->vals[op->dest.reg].offset = cfi->cfa.offset;

I'll change that to:

			cfi->vals[op->dest.reg].offset = cfa->offset;

To be more consistent with the rest of the code.

>  		}
>  
>  		break;
> 
>