[PATCH] RISC-V: Inform checksyscalls.sh about the rv32 ABI

[Arnd Bergmann]

On Mon, Sep 6, 2021 at 8:52 PM Palmer Dabbelt <palmerdabbelt at google.com> wrote:
>
> I remember having seen some build output from this before, but didn't
> know what it meant.  These are now showing up as errors.
>
> As far as I understand our 32-bit syscall ABI is fine, the issue here is
> simply that we don't need the syscalls in question because we never had
> the legacy versions to begin with.  One could imagine describing these
> constraints in an arch-generic way, but I'm not sure it's worth
> bothering until another arch comes along that behaves this way.
>
> Fixes: d4c08b9776b3 ("riscv: Use latest system call ABI")
> Signed-off-by: Palmer Dabbelt <palmerdabbelt at google.com>
> ---
>  arch/riscv/include/asm/unistd.h | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>
> diff --git a/arch/riscv/include/asm/unistd.h b/arch/riscv/include/asm/unistd.h
> index 6c316093a1e5..cbc2646b4662 100644
> --- a/arch/riscv/include/asm/unistd.h
> +++ b/arch/riscv/include/asm/unistd.h
> @@ -14,3 +14,17 @@
>  #include <uapi/asm/unistd.h>
>
>  #define NR_syscalls (__NR_syscalls)
> +
> +#if __BITS_PER_LONG == 32
> +/*
> + * RISC-V never had the 32-bit off/len syscall flavors, which means we don't
> + * need the the explicit off64/len64 versions.
> + */
> +#define __IGNORE_fstat64
> +#define __IGNORE_fstatat64

These should be in the checksyscalls.pl script: new architectures can all just
use statx() here. This has nothing to do with 32-bit off/len though, only
with time64.

> +/*
> + * RISC-V never had the 32-bit time_t syscall flavors, which means we don't
> + * need the explicit 64-bit versions.
> + */
> +#define __IGNORE_clone3
> +#endif

clone3 should be implemented, IIRC it's only missing because there is no
easy way to do an architecture-independent version.

        Arnd