From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:43515 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753083AbbHGUoQ (ORCPT ); Fri, 7 Aug 2015 16:44:16 -0400 Subject: Patch "x86/init: Clear 'init_level4_pgt' earlier" has been added to the 4.1-stable tree To: a.ryabinin@samsung.com, adech.fo@gmail.com, alpopov@ptsecurity.com, bp@alien8.de, dvyukov@google.com, glider@google.com, gregkh@linuxfoundation.org, mingo@kernel.org, peterz@infradead.org, tglx@linutronix.de, torvalds@linux-foundation.org Cc: , From: Date: Fri, 07 Aug 2015 13:44:15 -0700 Message-ID: <143898025519625@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled x86/init: Clear 'init_level4_pgt' earlier to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-init-clear-init_level4_pgt-earlier.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From d0f77d4d04b222a817925d33ba3589b190bfa863 Mon Sep 17 00:00:00 2001 From: Andrey Ryabinin Date: Thu, 2 Jul 2015 12:09:33 +0300 Subject: x86/init: Clear 'init_level4_pgt' earlier From: Andrey Ryabinin commit d0f77d4d04b222a817925d33ba3589b190bfa863 upstream. Currently x86_64_start_kernel() has two KASAN related function calls. The first call maps shadow to early_level4_pgt, the second maps shadow to init_level4_pgt. If we move clear_page(init_level4_pgt) earlier, we could hide KASAN low level detail from generic x86_64 initialization code. The next patch will do it. Signed-off-by: Andrey Ryabinin Cc: Alexander Popov Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Borislav Petkov Cc: Dmitry Vyukov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1435828178-10975-2-git-send-email-a.ryabinin@samsung.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/head64.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -166,6 +166,8 @@ asmlinkage __visible void __init x86_64_ /* clear bss before set_intr_gate with early_idt_handler */ clear_bss(); + clear_page(init_level4_pgt); + 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); @@ -177,7 +179,6 @@ asmlinkage __visible void __init x86_64_ */ load_ucode_bsp(); - clear_page(init_level4_pgt); /* set init_level4_pgt kernel high mapping*/ init_level4_pgt[511] = early_level4_pgt[511]; Patches currently in stable-queue which might be from a.ryabinin@samsung.com are queue-4.1/x86-kasan-fix-kasan-shadow-region-page-tables.patch queue-4.1/x86-kasan-fix-boot-crash-on-amd-processors.patch queue-4.1/x86-init-clear-init_level4_pgt-earlier.patch queue-4.1/x86-kasan-flush-tlbs-after-switching-cr3.patch