Re: [PATCH v3 7/8] sframe: Introduce in-kernel SFRAME_VALIDATION.

[Jens Remus]

Hello Dylan!

On 4/6/2026 8:49 PM, Dylan Hatch wrote:
> Generalize the __safe* helpers to support a non-user-access code path.
> Allow for kernel FDE read failures due to the presence of .rodata.text.
> This section contains code that can't be executed by the kernel
> direclty, and thus lies ouside the normal kernel-text bounds.

Nits: s/direclty/directly/ s/ouside/outside/

Could you please explain the issue?  How/why does .sframe for
.rodata.text pose an issue for .sframe verification?

> Signed-off-by: Dylan Hatch <dylanbhatch@xxxxxxxxxx>

> diff --git a/kernel/unwind/sframe.c b/kernel/unwind/sframe.c

> @@ -690,6 +699,13 @@ static int sframe_validate_section(struct sframe_section *sec)
>  		int ret;
>  
>  		ret = safe_read_fde(sec, i, &fde);
> +		/*
> +		 * Code in .rodata.text is not considered part of normal kernel
> +		 * text, but there is no easy way to prevent sframe data from
> +		 * being generated for it.
> +		 */
> +		if (ret && sec->sec_type == SFRAME_KERNEL)
> +			continue;
>  		if (ret)
>  			return ret;
>  
Thanks and regards,
Jens
-- 
Jens Remus
Linux on Z Development (D3303)
jremus@xxxxxxxxxx / jremus@xxxxxxxxxxxxx

IBM Deutschland Research & Development GmbH; Vorsitzender des Aufsichtsrats: Wolfgang Wendt; Geschäftsführung: David Faller; Sitz der Gesellschaft: Ehningen; Registergericht: Amtsgericht Stuttgart, HRB 243294
IBM Data Privacy Statement: https://www.ibm.com/privacy/