On Thu, Dec 13, 2007 at 09:23:26PM -0700, Eric W. Biederman wrote: > [EMAIL PROTECTED] (Eric W. Biederman) writes: > Ok. My analysis here was wrong. Currently pgprot_noncached and > ioremap_nocache are out of sync. With ioremap_nocache only specifying > _PAGE_PCD and pgprot_noncached specifying _PAGE_PCD | _PAGE_PWT. > > So I don't have a clue how someone could reprogram the mtrrs currently > and expect things to work. > > ... > > If we bother to ask ioremap for memory that is not cached, the last > thing in the world we want is the MTRRs upgrading that to write combining. > So ioremap_nocache has been slightly buggy for ages. ioremap_nocache > and PAGE_KERNEL_NOCACHE should get _PAGE_PWT added to their > definitions. > > Could we please get a cleanup patch at the beginning of this patchset > or that comes before it that fixes ioremap_nocache on x86? > > That will make us a lot more git-bisect safe.
Ok. I will send a separate patch fixing ioremap_nocache on x86. thanks, suresh -- 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/
