On Mon, Feb 08, 2016 at 02:50:19PM +0530, Aneesh Kumar K.V wrote: > With next generation power processor, we are having a new mmu model > [1] that require us to maintain a different linux page table format. > > Inorder to support both current and future ppc64 systems with a single > kernel we need to make sure kernel can select between different page > table format at runtime. With the new MMU (radix MMU) added, we will > have to dynamically switch between different protection map. Hence > override vm_get_page_prot instead of using arch_vm_get_page_prot. We > also drop arch_vm_get_page_prot since only powerpc used it. What's different about ISA v3.0 that means that the protection_map[] entries need to be different? If it's just different bit assignments for things like _PAGE_READ etc., couldn't we fix this up at early boot time by writing new values into protection_map[]? Is there a reason why that wouldn't work, or why you don't want to do that? Paul. -- 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>