On Sunday, 25 March 2007 14:56, Eric W. Biederman wrote: > "Rafael J. Wysocki" <[EMAIL PROTECTED]> writes: > > > Yes, in kernel/power/disk.c:power_down() . > > > > Please comment out the disable_nonboot_cpus() in there and retest (but > > please > > test the latest Linus' tree). > > <rant> > > Why do we even need a disable_nonboot_cpus in that path? machine_shutdown > on i386 and x86_64 should take care of that. Further the code that computes > the boot cpu is bogus (not all architectures require cpu == 0 to be > the boot cpu), and disabling non boot cpus appears to be a strong > x86ism, in the first place.
Yes. > If the only reason for disable_nonboot_cpus there is to avoid the > WARN_ON in init_low_mappings() we should seriously consider killing > it. We have considered it, but no one was sure that it was a good idea. > If we can wait for 2.6.22 the relocatable x86_64 patchset that > Andi has queued, has changes that kill the init_low_mapping() hack. I think we should kill the WARN_ON() right now, perhaps replacing it with a FIXME comment. > I'm not very comfortable with calling cpu_down in a common code path > right now either. I'm fairly certain we still don't have that > correct. So if we confine the mess that is cpu_down to #if > defined(CPU_HOTPLUG) && defined(CONFIG_EXPERIMENTAL) I don't care. > If we start using it everywhere I'm very nervous. > migration when bringing a cpu down is strongly racy, and I don't think > we actually put cpus to sleep properly either. I'm interested in all of the details, please. I seriously consider dropping cpu_up()/cpu_down() from the suspend code paths. Greetings, Rafael - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
