On Tue, 24 Apr 2012, Andrew Haley wrote: > On 04/23/2012 09:31 PM, Nicolas Pitre wrote: > > On Mon, 23 Apr 2012, Andrew Haley wrote: > > > >> On 04/23/2012 06:36 PM, Thomas Meyer wrote: > >>> I'm running the Ubuntun 2.6.38 Tegra2 kernel (because of their fbdev > >>> support) on top of Fedora 17 armv5el on an Toshiba AC100 Laptop. The > >>> rsyslog package crashed everytime because of the missing kernel support > >>> of cmpxchg64. So when relying on the kernel helpers make sure that the > >>> resp. kernel support exists. > >> > >> Indeed. I had to write a workaround in IcedTea (i.e. java) on ARM for > >> just this reason. If you can't depend on a kernel helper being there I > >> can't see it's of any use. > > > > Kernel helpers don't disappear with time. You therefore can probe for > > their availability (see the documentation) in case the kernel support > > could be backported, or just refuse to run if the kernel version isn't > > recent enough. This is not much different from relying on a new > > syscall. > > Indeed it is. What would I gain from adding such a test? All I can > see is extra complication, untested code paths, and larger programs. What alternative do you have, other than not using any atomic operations? > The untested code path is particularly nasty. How buggy the following code might be: fprintf(stderr, "Your kernel is too old, aborting\n") exit(1); ? Nicolas _______________________________________________ arm mailing list arm@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/arm
