On Tue, 2015-02-10 at 10:59 -0800, Dave Hansen wrote: > On 02/09/2015 02:45 PM, Toshi Kani wrote: > > Implement huge KVA mapping interfaces on x86. Select > > HAVE_ARCH_HUGE_VMAP when X86_64 or X86_32 with X86_PAE is set. > > Without X86_PAE set, the X86_32 kernel has the 2-level page > > tables and cannot provide the huge KVA mappings. > > Not that it's a big deal, but what's the limitation with the 2-level > page tables on 32-bit? We have a 4MB large page size available there > and we already use it for the kernel linear mapping. ioremap() calls arch-neutral ioremap_page_range() to set up I/O mappings with PTEs. This patch-set enables ioremap_page_range() to set up PUD & PMD mappings. With 2-level page table, I do not think this PUD/PMD mapping code works unless we add some special code. 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>