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

From: Heiko Carstens <[email-masked]>
Date: Tue, 27 Jul 2021 21:15:52 +0200

On Tue, Jul 27, 2021 at 08:49:40PM +0200, Arnd Bergmann wrote:
> On Tue, Jul 27, 2021 at 8:38 PM Heiko Carstens <[email-masked]> 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.

You are remembering correctly, probably because you implemented it ;)
I totally forgot - sorry for the noise!