Re: [Qemu-devel] proposal: drop linux-user unicore32 support from QEMU

[Riku Voipio]

> > The problem we see is that the system call numbers in qemus
> > unicore32/syscall_nr.h dont match what is linux mainline kernel. From the
> > toolchain linked, you seem to have kernel headers and syscall numbers
> > based on a custom 2.6.32 fork. If one builds unicore32 binaries based on
> > Linux 4.4 kernel headers, they will not work qemu. OTOH the binary built
> > with the toolchain you linked, would not work with linux 4.4. This
> > disparity is what we'd like to get fixed.

> OK, I see.
> I'd send kernel-patches merge request to linus, but the patches hadn't be
> merged.
> I'll work on it. Hopefully it'll be done before mid Oct.

This blocks some cleanup work in linux-user code. For example everyone has
moved over from epoll_wait to epoll_pwait. However, I can't remove the now
unneeded TARGET_NR_epoll_pwait, because nobody is keeping unicore32 syscall
list upto date.

I think we should temporarily disable the unicore32-linux-user target, and
re-enable it in be 2.8 softfreeze if the system calls get updated.

Riku