Re: [PATCH] iommu: Add Kconfig help text for IOMMU_SVA

From: Linus Torvalds
Date: Sat May 06 2023 - 11:43:35 EST


On Sat, May 6, 2023 at 6:27 AM Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> wrote:
>
> Shared Virtual Addressing (SVA) is not immediately intuitive to people
> who work outside IOMMU subsystem, add some explanation to make it less
> opaque.

So the patch has at least two problems.

The first is that you corrupted the SPDX line.

But the second is that the change from

- bool
+ bool "Shared Virtual Addressing"

means that now Kconfig *asks* about this thing, which was never the
intent. The other Kconfig options that need it all do a

select IOMMU_SVA

to get it picked.

I suspect that's why it then causes errors - because now the test
robot can enable the option even in situations where it makes no sense
and doesn't work.

So no, it's not that the option needs a help entry that can be queried
at Kconfig time. It's that the option needs a name that makes sense
and isn't some random jumble of letters that is only understandable to
people who already know exactly what it is.

Linus