Re: [PATCH v3 5/5] riscv: vdso: Implement __vdso_futex_robust_try_unlock()

[Nam Cao]

Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx> writes:
> I don't think we would get such an error currently.
> The cc-option check in the Makefile will fall back to non-zacas for the
> compat vDSO, but arch_futex_robust_unlock_get_pop() will treat it as zacas.

Switching to .option and the cc-option will be gone. See below.

> Ok. I don't understand the .option suggestion :-)

We wouldn't touch -march compile option in Makefiles. Instead, we do

.option push
.option arch, <extension name>
<instruction requiring extension>
.option pop

Whenever the ZACAS instruction is used.

See
https://lore.kernel.org/lkml/20260717-riscv-no-zacas-zabha-in-march-v1-1-82b5b0799fb6@xxxxxxxxxxx/

Nam