On Thu, 2010-03-04 at 21:40 +0000, Russell King - ARM Linux wrote: > On Fri, Mar 05, 2010 at 08:28:34AM +1100, Benjamin Herrenschmidt wrote: > > I don't think there's a core or driver problem in this specific case. As > > we discussed earlier, I believe the problem is that ARM considers a > > fresh page out of the page cache as "clean" instead of "dirty", and > > inverting that like we do on powerpc will fix their problem too. > > The only concern is that it means we treat anonymous pages as dirty > by default. > > That's quite sub-optimal since we take care (eg) on write faults to > copy the page and take care of the cache issues while we do that - If you do the cache handling inside your copy_user_highpage() then you can just set PG_arch_1 stuff there. > whether that be remapping the page to be coherent with the user > address, or cleaning each cache line as we copy the data. > > Of course, the simple solution is to also arrange for PG_arch_1 to be > set in this case. Right. Cheers, Ben. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
