Re: [PATCH 23/30] microblaze_mmu_v1: Enable fork syscall for MMU and add fork as vfork for noMMU

Arnd Bergmann
2009-04-29T11:32:21Z

On Wednesday 29 April 2009, Michal Simek wrote:
> >> +sys_fork_wrapper:
> >>  sys_vfork_wrapper:
> >>        brid    sys_vfork
> >>        addk    r5, r1, r0
> >
> > NACK!  If only it was that easy :)
> >
> > On noMMU we cannot just silently call vfork() if the application tries
> > to fork() - you have to return -ENOSYS (or is there a better one?).
> > This will just require a small sys_fork_wrapper in entry-nommu.S.
>
> I will call for noMMU kernel ni_syscall which solve that problem.
> (Arnd do it in his patches too)
>

Note that my patches did not call the wrappers correctly, this
has to be fixed to make them work first.

For the fork call on !CONFIG_MMU, we should probably just add
a cond_syscall() in kernel/sys_ni.c near sys_msync() and
the other MMU specific calls.