Re: [PATCH 1/4] x86: add __X32_COND_SYSCALL() macro

From: Brian Gerst
Date: Sat Sep 19 2020 - 14:05:44 EST


An alternative to the patch I proposed earlier would be to use aliases
with the __x32_ prefix for the common syscalls.

--
Brian Gerst

On Sat, Sep 19, 2020 at 1:14 PM <hpa@xxxxxxxxx> wrote:
>
> On September 19, 2020 9:23:22 AM PDT, Andy Lutomirski <luto@xxxxxxxxxx> wrote:
> >On Fri, Sep 18, 2020 at 10:35 PM Christoph Hellwig <hch@xxxxxxxxxxxxx>
> >wrote:
> >>
> >> On Fri, Sep 18, 2020 at 03:24:36PM +0200, Arnd Bergmann wrote:
> >> > sys_move_pages() is an optional syscall, and once we remove
> >> > the compat version of it in favor of the native one with an
> >> > in_compat_syscall() check, the x32 syscall table refers to
> >> > a __x32_sys_move_pages symbol that may not exist when the
> >> > syscall is disabled.
> >> >
> >> > Change the COND_SYSCALL() definition on x86 to also include
> >> > the redirection for x32.
> >> >
> >> > Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> >>
> >> Adding the x86 maintainers and Brian Gerst. Brian proposed another
> >> problem to the mess that most of the compat syscall handlers used by
> >> x32 here:
> >>
> >> https://lkml.org/lkml/2020/6/16/664
> >>
> >> hpa didn't particularly like it, but with your and my pending series
> >> we'll soon use more native than compat syscalls for x32, so something
> >> will need to change..
> >
> >I'm fine with either solution.
>
> My main objection was naming. x64 is a widely used synonym for x86-64, and so that is confusing.
>
> --
> Sent from my Android device with K-9 Mail. Please excuse my brevity.