On Fri, 2012-09-07 at 08:40 +0100, Jan Beulich wrote: > >>> On 06.09.12 at 19:07, "H. Peter Anvin" <h...@zytor.com> wrote: > > Anyone care to refresh my memory why we can't use the "global" > > 1:1+kernel map, possibly with some improvements (which would benefit the > > users of those maps too)? With that I mean initial_page_map on i386 and > > trampoline_pgd on x86-64... > > I don't think you want anything inserted in the low part of those > (kernel-only) page tables, not even transiently.
There are already things inserted into the low part of those page tables. In fact, the main purpose is to provide a 1:1 mapping for realmode code. See machine_real_restart(). I think there's definitely merit to the approach Peter outlined above. There's a variety of places in arch/x86 where a 1:1 mapping is needed. It would be good to have a single pagetable that provides this. -- 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/
