On Wed, 2014-09-10 at 11:29 -0700, Andy Lutomirski wrote: > On Wed, Sep 10, 2014 at 9:51 AM, Toshi Kani <toshi.kani@xxxxxx> wrote: : > > +#ifndef ARCH_HAS_IOREMAP_WT > > +#define ioremap_wt ioremap_nocache > > +#endif > > + > > This is a little bit sad. I wouldn't be too surprised if there are > eventually users who prefer WC or WB over UC if WT isn't available > (and they'll want a corresponding way to figure out what kind of fence > to use). Right, this redirection is not ideal for the performance, but it is done this way for the correctness. WT & UC have strongly ordered writes, but WB & WC do not. Thanks, -Toshi -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>