Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753886AbbGAJIS (ORCPT ); Wed, 1 Jul 2015 05:08:18 -0400 Received: from mail-wg0-f43.google.com ([74.125.82.43]:33518 "EHLO mail-wg0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753473AbbGAJHq (ORCPT ); Wed, 1 Jul 2015 05:07:46 -0400 Date: Wed, 1 Jul 2015 11:07:40 +0200 From: Ingo Molnar To: Andrey Ryabinin Cc: Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner , x86@kernel.org, Andrey Konovalov , Andrew Morton , Borislav Petkov , Alexander Popov , Dmitry Vyukov , Alexander Potapenko , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH 1/5] x86_64: fix kasan shadow region page tables Message-ID: <20150701090740.GA16645@gmail.com> References: <1435654466-8714-1-git-send-email-a.ryabinin@samsung.com> <1435654811-8915-1-git-send-email-a.ryabinin@samsung.com> <1435654811-8915-2-git-send-email-a.ryabinin@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1435654811-8915-2-git-send-email-a.ryabinin@samsung.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1739 Lines: 54 * Andrey Ryabinin 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. That way if anything breaks in the generic code due to this change we have a simple commit to bisect to. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/