Re: [PATCH 5/6] s390/Kconfig: Select ARCH_SUPPORTS_CFI

Heiko Carstens <[email protected]> Mon, 27 Jul 2026 15:52:29 +0200
Newsgroups dev.linux.lists.llvm,org.kernel.vger.bpf,org.kernel.vger.linux-kernel,org.kernel.vger.linux-s390
Message-ID <[email protected]>
On Fri, Jul 24, 2026 at 06:00:04PM -0700, Nathan Chancellor wrote:
> Hi Heiko,
> 
> On Fri, Jul 24, 2026 at 04:13:17PM +0200, Heiko Carstens wrote:
> > With all prerequisites in place select ARCH_SUPPORTS_CFI.
> > 
> > Note that this support is supposed to work with the generic kcfi support
> > which is provided by clang. This comes with a couple of limitations:
> 
> Consider adding
> 
>   select ARCH_USES_CFI_GENERIC_LLVM_PASS if CC_IS_CLANG
> 
> to this change in case there are problems such as the one worked around
> by commit c57f5fee54df ("libeth: xdp: Disable generic kCFI pass for
> libeth_xdp_tx_xmit_bulk()"). Whenever clang grows an s390 backend
> expansion for kCFI, that can be version gated pretty easily.

Thanks, I'll add that.

> I will test this series fully next week.

Highly appreciated!

I'm going to send a v2 soon, which addresses your feedback, and
hopefully all AI findings too.