Re: [PATCH v2] RISC-V: Add CONFIG_{NON,}PORTABLE

From: Palmer Dabbelt
Date: Sat May 21 2022 - 16:46:54 EST


On Thu, 14 Apr 2022 05:47:33 PDT (-0700), Niklas.Cassel@xxxxxxx wrote:
On Wed, Apr 13, 2022 at 06:40:10PM -0700, Palmer Dabbelt wrote:
From: Palmer Dabbelt <palmer@xxxxxxxxxxxx>

The RISC-V port has collected a handful of options that are
fundamentally non-portable. To prevent users from shooting themselves
in the foot, hide them all behind a config entry that explicitly calls
out that non-portable binaries may be produced.

Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>

---

Changes since v1:

* Fix a bunch of spelling mistakes.
* Move NONPORTABLE under the "Platform type" sub-heading.
* Fix the rv32i dependency.
---
arch/riscv/Kconfig | 28 ++++++++++++++++++++++++++--
1 file changed, 26 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 5adcbd9b5e88..3d8eb44eb889 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -213,6 +213,21 @@ source "arch/riscv/Kconfig.erratas"
menu "Platform type"
+config NONPORTABLE
+ bool "Allow configurations that result in non-portable kernels"
+ help
+ RISC-V kernel binaries are compatible between all known systems
+ whenever possible, but there are some use cases that can only be
+ satisfied by configurations that result in kernel binaries that are
+ not portable between systems.
+
+ Selecting N does not guarantee kernels will be portable to all knows

nit: s/knows/known ?

Thanks. Turns out I've got a bit of an issue here and this results in the
defconfigs breaking, so I've got ahead and sent a v3 that includes the
necessary bits to make those work along with this fixed up.

Kind regards,
Niklas