Re: [PATCH v13 17/18] unwind_user/sframe/x86: Enable sframe unwinding on x86

[Jens Remus <jremus@linux.ibm.com>]

On 1/27/2026 4:05 PM, Jens Remus wrote:

> diff --git a/arch/x86/include/asm/unwind_user.h b/arch/x86/include/asm/unwind_user.h

> @@ -15,6 +15,40 @@ static inline int unwind_user_word_size(struct pt_regs *regs)
>  	return user_64bit_mode(regs) ? 8 : 4;
>  }
>  
> +static inline int unwind_user_get_reg(unsigned long *val, unsigned int regnum)
> +{
> +#ifdef CONFIG_X86_64
> +	const struct pt_regs *regs = task_pt_regs(current);
> +
> +	switch (regnum) {
> +	/* DWARF register numbers 0..15 */
> +	case  0: *val = regs->ax; break;
> +	case  1: *val = regs->dx; break;
> +	case  2: *val = regs->cx; break;
> +	case  3: *val = regs->bx; break;
> +	case  4: *val = regs->si; break;
> +	case  5: *val = regs->di; break;
> +	case  6: *val = regs->bp; break;
> +	case  7: *val = regs->sp; break;
> +	case  8: *val = regs->r8; break;
> +	case  9: *val = regs->r9; break;
> +	case 10: *val = regs->r10; break;
> +	case 11: *val = regs->r11; break;
> +	case 12: *val = regs->r12; break;
> +	case 13: *val = regs->r13; break;
> +	case 14: *val = regs->r14; break;
> +	case 15: *val = regs->r15; break;
> +	default:
> +		return -EINVAL;
> +	}
> +	return 0;
> +#else /* !CONFIG_X86_64 */
> +	return -EINVAL;
> +#endif /* !CONFIG_X86_64 */
> +

Nit: Superfluous empty line.

> +}
> +#define unwind_user_get_reg unwind_user_get_reg
> +
>  #endif /* CONFIG_UNWIND_USER */
>  
>  #ifdef CONFIG_HAVE_UNWIND_USER_FP
Regards,
Jens
-- 
Jens Remus
Linux on Z Development (D3303)
jremus@de.ibm.com / jremus@linux.ibm.com

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