Re: [PATCH 0/8] unwind, arm64: add sframe unwinder for kernel

Song Liu
2025-02-18T18:20:22Z

Hi Josh,

On Mon, Feb 17, 2025 at 10:37 PM Josh Poimboeuf <jpoimboe@kernel.org> wrote:
>
> On Mon, Feb 17, 2025 at 08:38:22PM -0800, Song Liu wrote:
> > On Fri, Feb 14, 2025 at 3:23 PM Josh Poimboeuf <jpoimboe@kernel.org> wrote:
> > > Poking around the arm64 module code, arch/arm64/kernel/module-plts.c
> > > is looking at all the relocations in order to set up the PLT. That also
> > > needs to be done for klp relas, or are your patches already doing that?
> >
> > I don't think either version (this set and my RFC) added logic for PLT.
> > There is some rela logic on the kpatch-build side. But I am not sure
> > whether it is sufficient.
>
> The klp relas looked ok. I didn't see any signs of kpatch-build doing
> anything wrong. AFAICT the problem is that module-plts.c creates PLT
> entries for regular relas but not klp relas.

In my tests (with printk) module-plts.c processes the .
klp.rela.vmlinux..text.copy_process section just like any other .rela.*
sections. Do we need special handling of the klp.rela.* sections?

Thanks,
Song