On Thu, Oct 12, 2017 at 02:42:49AM +0300, Dmitry Osipenko wrote: > On 11.10.2017 11:22, Abbott Liu wrote: > > +void __init kasan_map_early_shadow(pgd_t *pgdp) > > +{ > > + int i; > > + unsigned long start = KASAN_SHADOW_START; > > + unsigned long end = KASAN_SHADOW_END; > > + unsigned long addr; > > + unsigned long next; > > + pgd_t *pgd; > > + > > + for (i = 0; i < PTRS_PER_PTE; i++) > > + set_pte_at(&init_mm, KASAN_SHADOW_START + i*PAGE_SIZE, > > + &kasan_zero_pte[i], pfn_pte( > > + virt_to_pfn(kasan_zero_page), > > + __pgprot(_L_PTE_DEFAULT | L_PTE_DIRTY | L_PTE_XN))); > > Shouldn't all __pgprot's contain L_PTE_MT_WRITETHROUGH ? One of the architecture restrictions is that the cache attributes of all aliases should match (but there is a specific workaround that permits this, provided that the dis-similar mappings aren't accessed without certain intervening instructions.) Why should it be L_PTE_MT_WRITETHROUGH, and not the same cache attributes as the lowmem mapping? -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up According to speedtest.net: 8.21Mbps down 510kbps up -- 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>