Re: [PATCH v2 6/9] s390/module: Use s390_kernel_write() for late relocations

[Joe Lawrence]

On 4/30/20 12:48 PM, Josh Poimboeuf wrote:
> On Thu, Apr 30, 2020 at 10:38:21AM -0400, Joe Lawrence wrote:
> > On Thu, Apr 23, 2020 at 01:10:30PM -0500, Josh Poimboeuf wrote:
> > This is more of note for the future, but when/if we add livepatch
> > support on arm64 we'll need to make the very same adjustment there as
> > well.  See the following pattern:
> >
> > arch/arm64/kernel/module.c:
> >
> >    reloc_insn_movw()
> >    reloc_insn_imm()
> >    reloc_insn_adrp()
> >
> >      *place = cpu_to_le32(insn);
> >
> > maybe something like aarch64_insn_patch_text_nosync() could be used
> > there, I dunno. (It looks like ftrace and jump_labels are using that
> > interface.)
> >
> > This is outside the scope of the patchset, but I thought I'd mention it
> > as I was curious to see how other arches were currently handling their
> > relocation updates.
>
> True... I suspect your klp-convert selftests will catch that?

Indeed.  Actually I had hacked enough livepatch code support on ARM to 
see what happened when converting and loading the test patches :)

-- Joe