>>> One Thousand Gnomes <gno...@lxorguk.ukuu.org.uk> 08/20/14 2:08 PM >>> >> The Linux kernel currently supports only 4 different cache modes. The PAT MSR >> is set up in a way that the setting of _PAGE_PAT in a pte doesn't matter: the >> top 4 entries in the PAT MSR are the same as the 4 lower entries. >> >> This results in the kernel not supporting e.g. write-through mode. Especially >> this cache mode would speed up drivers of video cards which now have to use >> uncached accesses. > >Pentium II erratum A52 (and similar on quite a few other processors)
But you're aware that for the last two major releases Xen hasn't been supporting 32-bit CPUs at all anymore? I.e. why should we limit functionality under Xen based on errata on 64-bit-incapable CPUs? Jan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
