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

Jens Remus
2026-04-16T15:05:04Z

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@google.com>

> 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@de.ibm.com / jremus@linux.ibm.com

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