On 07/01/2015 12:07 PM, Ingo Molnar wrote: > > * Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx> wrote: > >> diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c >> index 5a46681..f129a9a 100644 >> --- a/arch/x86/kernel/head64.c >> +++ b/arch/x86/kernel/head64.c >> @@ -161,11 +161,12 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data) >> /* Kill off the identity-map trampoline */ >> reset_early_page_tables(); >> >> - kasan_map_early_shadow(early_level4_pgt); >> - >> - /* clear bss before set_intr_gate with early_idt_handler */ >> clear_bss(); >> >> + clear_page(init_level4_pgt); >> + >> + kasan_early_init(); >> + >> for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) >> set_intr_gate(i, early_idt_handler_array[i]); >> load_idt((const struct desc_ptr *)&idt_descr); >> @@ -177,12 +178,9 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data) >> */ >> load_ucode_bsp(); >> >> - clear_page(init_level4_pgt); >> /* set init_level4_pgt kernel high mapping*/ >> init_level4_pgt[511] = early_level4_pgt[511]; >> >> - kasan_map_early_shadow(init_level4_pgt); >> - >> x86_64_start_reservations(real_mode_data); >> } >> > > So this changes generic code (moves the clear_page(init_level4_pgt) call), but the > changelog claims it's a KASAN-specific change. > > Please split this into two patches: the first one does the generic change, the > second one the KASAN specific one. > Hm... We will need to backport that generic change to stable, because second change depends on it. So, maybe split this on three changes: #1 fix kasan page tables (without touching clear_page() or kasan_map_early_shadow(init_level4_pgt)) #2 generic move clear_page() #3 clean up kasan initialization (move kasan_map_early_shadow(init_level4_pgt)). Only #1 will have stable tag. Does that makes sense? -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html