> What cases did you have in mind? Mainly mapping memory which is rather tricky.
> From current Intel 64 and IA-32 Architectures Software Developer's Manual > Volume 3A: System Programming Guide, section 10.5.2: If you look at the detailed table it's not that simple. > > Then there are old CPU errata that need to be handled etc. > > I don't see a problem with having CONFIG_PAT depend on P4/Athlon or > newer to avoid such workarounds for now. Better to have something > there which works in (only) 80% of the cases, than nothing at all. Agreed, but the patch doesn't do that. > > You didn't solve all that at all. If it was as simple as your patch > > we would have long done it already. > > Perhaps this feature can be marked as WIP to allow this to move > forward while corner-cases are worked out. Adding such a go/no-go We're not going to have potentially cache corrupting features as WIP. The last time one such bug took months to track down. > barrier will hamper progress we do see, as it has done already for > years. Because it's not simple and nobody has done it properly yet. > The PCI ordering config option years ago was a similar case, since > various drivers didn't issue wmb()s until they were fixed up. wmb alone is not enough for PCI ordering. -Andi - 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/
