Re: [PATCH 14/15] arch: add split IPC system calls where needed

Michael Ellerman
2019-01-16T00:10:25Z

Arnd Bergmann <arnd@arndb.de> writes:
> On Mon, Jan 14, 2019 at 4:59 AM Michael Ellerman <mpe@ellerman.id.au> wrote:
>> Arnd Bergmann <arnd@arndb.de> writes:
>> > arch/m68k/kernel/syscalls/syscall.tbl | 11 +++++++++++
>> > arch/mips/kernel/syscalls/syscall_o32.tbl | 11 +++++++++++
>> > arch/powerpc/kernel/syscalls/syscall.tbl | 12 ++++++++++++
>>
>> I have some changes I'd like to make to our syscall table that will
>> clash with this.
>>
>> I'll try and send them today.
>
> Ok. Are those for 5.0 or 5.1? If they are intended for 5.0, it would be
> nice for me to have a branch based on 5.0-rc1 that I can put
> the other patches on top of.

For 5.1.

I can put them in a topic branch for you.

>> > diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
>> > index db3bbb8744af..1bffab54ff35 100644
>> > --- a/arch/powerpc/kernel/syscalls/syscall.tbl
>> > +++ b/arch/powerpc/kernel/syscalls/syscall.tbl
>> > @@ -425,3 +425,15 @@
>> > 386 nospu pkey_mprotect sys_pkey_mprotect
>> > 387 nospu rseq sys_rseq
>> > 388 nospu io_pgetevents sys_io_pgetevents compat_sys_io_pgetevents
>> > +# room for arch specific syscalls
>> > +392 64 semtimedop sys_semtimedop
>> > +393 common semget sys_semget
>> > +394 common semctl sys_semctl compat_sys_semctl
>> > +395 common shmget sys_shmget
>> > +396 common shmctl sys_shmctl compat_sys_shmctl
>> > +397 common shmat sys_shmat compat_sys_shmat
>> > +398 common shmdt sys_shmdt
>> > +399 common msgget sys_msgget
>> > +400 common msgsnd sys_msgsnd compat_sys_msgsnd
>> > +401 common msgrcv sys_msgrcv compat_sys_msgrcv
>> > +402 common msgctl sys_msgctl compat_sys_msgctl
>>
>> We already have a gap at 366-377 from when we tried to add the split IPC
>> calls a few years back.
>>
>> I guess I don't mind leaving that gap and using the common numbers as
>> you've done here.
>>
>> But it would be good to add a comment pointing out that we have room
>> at 366 for more arch specific syscalls as well.
>
> Ah, I missed that. I've added this to my patch now:
>
> index 5c0936d862fc..2ddfba536d5f 100644
> --- a/arch/powerpc/kernel/syscalls/syscall.tbl
> +++ b/arch/powerpc/kernel/syscalls/syscall.tbl
> @@ -460,6 +460,7 @@
> 363 spu switch_endian sys_ni_syscall
> 364 common userfaultfd sys_userfaultfd
> 365 common membarrier sys_membarrier
> +# 366-377 originally left for IPC, now unused
> 378 nospu mlock2 sys_mlock2
> 379 nospu copy_file_range sys_copy_file_range
> 380 common preadv2 sys_preadv2
> compat_sys_preadv2

Thanks.

cheers