Re: [PATCH v10 06/13] iommu/arm-smmu-v3: Add ARM_SMMU_OPT_KDUMP_ADOPT for kdump kernel

From: Will Deacon

Date: Mon Oct 05 2026 - 02:33:11 EST


On Sun, Oct 04, 2026 at 01:47:16PM -0700, Nicolin Chen wrote:
> On Sun, Oct 04, 2026 at 02:25:07PM +0100, Will Deacon wrote:
> > On Sun, Aug 30, 2026 at 04:18:07PM -0700, Nicolin Chen wrote:
> > > drivers/iommu/arm/arm-smmu-v3/Makefile | 1 +
> > > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 21 ++
> > > .../iommu/arm/arm-smmu-v3/arm-smmu-v3-kdump.c | 229 ++++++++++++++++++
> >
> > Please don't put this here. The live update / handover stuff is going to
> > need very similar logic (see the RFC from Pranjal) and I don't fancy
> > having to rename or resplit this file when that comes along.
> >
> > Maybe just stick all of arm-smmu-v3-kexec.c and arm-smmu-v3-kdump.c into
> > arm-smmu-v3-handover.c or something?
>
> Hmm, Pranjal and I already aligned that cleanly. And there is no
> further rename/resplit in his series.
>
> arm-smmu-v3-kexec: common helpers for both
> arm-smmu-v3-kdump: kdump specific (my series)
> arm-smmu-v3-liveupdate: liveupdate specific (Pranj's)
>
> Each of them is built on a separate config:
> arm_smmu_v3-$(CONFIG_ARM_SMMU_V3_KEXEC) += arm-smmu-v3-kexec.o
> arm_smmu_v3-$(CONFIG_IOMMU_LIVEUPDATE) += arm-smmu-v3-liveupdate.o
> arm_smmu_v3-$(CONFIG_CRASH_DUMP) += arm-smmu-v3-kdump.o
>
> If we put everything into one big file, we'd add the two individual
> config guards internally, which isn't as clean as currently IMHO.
>
> Note that the kdump file has a very long notes (kdump specific).

I dunno, three files seems way over the top for this imo. I'd rather have
one (even if it uses preprocessor guards internally) otherwise it just
seems inevitable that we'll have random internals exposed from one file
to the other, or duplication of logic or both. Even if we end up splitting
it eventually, I'd much rather start from a position where everything is
in one place.

Will