Re: [PATCH v5 4/6] mm: simplify compat numa syscalls

[Arnd Bergmann]

On Tue, Jul 27, 2021 at 8:38 PM Heiko Carstens <hca@xxxxxxxxxxxxx> wrote:
>
> -268  common    mbind                   sys_mbind                       compat_sys_mbind
> -269  common    get_mempolicy           sys_get_mempolicy               compat_sys_get_mempolicy
> -270  common    set_mempolicy           sys_set_mempolicy               compat_sys_set_mempolicy
> +268  common    mbind                   sys_mbind                       sys_mbind
> +269  common    get_mempolicy           sys_get_mempolicy               sys_get_mempolicy
> +270  common    set_mempolicy           sys_set_mempolicy               sys_set_mempolicy
>
> would remove compat_ptr() conversion from nmask above if I'm not mistaken.

Maybe I'm misremembering how compat syscalls work on s390. Doesn't
SYSCALL_DEFINEx(sys_mbind) still create two entry points __s390x_sys_mbind()
and __s390_sys_mbind() with different argument conversion (__SC_CAST vs
__SC_COMPAT_CAST)? I thought that was the whole point of the macros.

        Arnd