[PATCH v2 1/6] riscv: ftrace: support fastcc in Clang for WITH_ARGS

[Andy Chiu]

On Tue, Aug 13, 2024 at 7:09 PM Björn Töpel <bjorn at kernel.org> wrote:
>
> Andy Chiu <andy.chiu at sifive.com> writes:
>
> > Some caller-saved registers which are not defined as function arguments
> > in the ABI can still be passed as arguments when the kernel is compiled
> > with Clang. As a result, we must save and restore those registers to
> > prevent ftrace from clobbering them.
> >
> > - [1]: https://reviews.llvm.org/D68559
> >
> > Reported-by: Evgenii Shatokhin <e.shatokhin at yadro.com>
> > Closes: https://lore.kernel.org/linux-riscv/7e7c7914-445d-426d-89a0-59a9199c45b1@yadro.com/
> > Acked-by: Nathan Chancellor <nathan at kernel.org>
> > Signed-off-by: Andy Chiu <andy.chiu at sifive.com>
>
> Shouldn't this be a separate fix? Still reading the details, but it
> smells like something what should be disabled when building w/ LLVM, no?

Yes, this is a fix. My intention was indicating the dependency. So
people won't hit into trouble testing it. I can send it in a separate
series.

Thanks,
Andy