Re: [libvirt] [PATCH] virprocess: Extend list of platforms for setns wrapper

On Mon, Sep 15, 2014 at 05:20:46PM +0200, Michal Privoznik wrote: > On 15.09.2014 17:15, Martin Kletzander wrote: > >On Mon, Sep 15, 2014 at 03:43:55PM +0200, Michal Privoznik wrote: > >>Currently, the setns() wrapper is supported only for x86_64 and i686 > >>which leaves us failing to build on other platforms like arm, aarch64 > >>and so on. This means, that the wrapper needs to be extended to those > >>platforms and make to fail on runtime not compile time. > >> > >>The syscall numbers for other platforms was fetched using this > >>command: > >> > >>kernel.git $ git grep "define.*__NR_setns" | grep -e arm -e powerpc -e > >>s390 > >>arch/arm/include/uapi/asm/unistd.h:#define > >>__NR_setns (__NR_SYSCALL_BASE+375) > >>arch/arm64/include/asm/unistd32.h:#define __NR_setns 375 > >>arch/powerpc/include/uapi/asm/unistd.h:#define > >>__NR_setns 350 > >>arch/s390/include/uapi/asm/unistd.h:#define __NR_setns 339 > >> > >>Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; > >>--- > >>src/util/virprocess.c | 18 ++++++++++++------ > >>1 file changed, 12 insertions(+), 6 deletions(-) > >> > > > >NACK, we shouldn't be duplicating syscall definitions. There should > >be AC_CHECK_FUNCS([setns]) (instead of AC_CHECK_FUNCS_ONCE() for the > >syscall) and having with_lxc = "yes" and ac_cv_func_setns != "yes" > >should result in an error. > > The only problem with this might be that on systems with older glibc (and > there is plenty of them) libvirt will fail to build / miss this feature. And > it's not that the kernel doesn't support the namesapces. But let me see if I > can get some ACKs on that approach you're suggesting. That's basically what the code did before we added the #define or NR_setns. We took the patch specifically to help Debian where the kernel has it but glibc is outdated.

Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|