Re: [PATCH 1/7] x86/syscalls: fix -Wmissing-prototypes warnings from COND_SYSCALL()

[Masahiro Yamada]

On Thu, Mar 25, 2021 at 8:48 PM Mickaël Salaün <mic@xxxxxxxxxxx> wrote:
>
> Hi Masahiro,
>
> What is the status of this patch? Could you please push it to -next?
> This would avoid emails from lkp:
> https://lore.kernel.org/linux-security-module/202103191423.Jl0jVzfL-lkp@xxxxxxxxx/


Hmm, I also want to know the answer.
This is the *third* time that I resent this patch
to the x86 ML.

This is a territory of the x86 subsystem
because it is only touching
arch/x86/include/asm/syscall_wrapper.h
It is preferred to get this in via the x86 tree.

x86 Maintainers,
could you take a look please?





> Thanks,
>  Mickaël
>
> On 01/03/2021 14:15, Masahiro Yamada wrote:
> > Building kernel/sys_ni.c with W=1 emits tons of -Wmissing-prototypes
> > warnings.
> >
> > $ make W=1 kernel/sys_ni.o
> >   [ snip ]
> >   CC      kernel/sys_ni.o
> > In file included from kernel/sys_ni.c:10:
> > ./arch/x86/include/asm/syscall_wrapper.h:83:14: warning: no previous prototype for '__x64_sys_io_setup' [-Wmissing-prototypes]
> >    83 |  __weak long __##abi##_##name(const struct pt_regs *__unused) \
> >       |              ^~
> > ./arch/x86/include/asm/syscall_wrapper.h:100:2: note: in expansion of macro '__COND_SYSCALL'
> >   100 |  __COND_SYSCALL(x64, sys_##name)
> >       |  ^~~~~~~~~~~~~~
> > ./arch/x86/include/asm/syscall_wrapper.h:256:2: note: in expansion of macro '__X64_COND_SYSCALL'
> >   256 |  __X64_COND_SYSCALL(name)     \
> >       |  ^~~~~~~~~~~~~~~~~~
> > kernel/sys_ni.c:39:1: note: in expansion of macro 'COND_SYSCALL'
> >    39 | COND_SYSCALL(io_setup);
> >       | ^~~~~~~~~~~~
> > ./arch/x86/include/asm/syscall_wrapper.h:83:14: warning: no previous prototype for '__ia32_sys_io_setup' [-Wmissing-prototypes]
> >    83 |  __weak long __##abi##_##name(const struct pt_regs *__unused) \
> >       |              ^~
> > ./arch/x86/include/asm/syscall_wrapper.h:120:2: note: in expansion of macro '__COND_SYSCALL'
> >   120 |  __COND_SYSCALL(ia32, sys_##name)
> >       |  ^~~~~~~~~~~~~~
> > ./arch/x86/include/asm/syscall_wrapper.h:257:2: note: in expansion of macro '__IA32_COND_SYSCALL'
> >   257 |  __IA32_COND_SYSCALL(name)
> >       |  ^~~~~~~~~~~~~~~~~~~
> > kernel/sys_ni.c:39:1: note: in expansion of macro 'COND_SYSCALL'
> >    39 | COND_SYSCALL(io_setup);
> >       | ^~~~~~~~~~~~
> >   ...
> >
> > __SYS_STUB0() and __SYS_STUBx() defined a few lines above have forward
> > declarations. Let's do likewise for __COND_SYSCALL() to fix the
> > warnings.
> >
> > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> > Tested-by: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx>
> > ---
> >
> >  arch/x86/include/asm/syscall_wrapper.h | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/x86/include/asm/syscall_wrapper.h b/arch/x86/include/asm/syscall_wrapper.h
> > index a84333adeef2..80c08c7d5e72 100644
> > --- a/arch/x86/include/asm/syscall_wrapper.h
> > +++ b/arch/x86/include/asm/syscall_wrapper.h
> > @@ -80,6 +80,7 @@ extern long __ia32_sys_ni_syscall(const struct pt_regs *regs);
> >       }
> >
> >  #define __COND_SYSCALL(abi, name)                                    \
> > +     __weak long __##abi##_##name(const struct pt_regs *__unused);   \
> >       __weak long __##abi##_##name(const struct pt_regs *__unused)    \
> >       {                                                               \
> >               return sys_ni_syscall();                                \
> >



--
Best Regards
Masahiro Yamada