From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753176AbbI1TYm (ORCPT ); Mon, 28 Sep 2015 15:24:42 -0400 Received: from mga14.intel.com ([192.55.52.115]:6479 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751479AbbI1TSU (ORCPT ); Mon, 28 Sep 2015 15:18:20 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,604,1437462000"; d="scan'208";a="570002976" Subject: [PATCH 07/25] x86, pkeys: new page fault error code bit: PF_PK To: dave@sr71.net Cc: borntraeger@de.ibm.com, x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, dave.hansen@linux.intel.com From: Dave Hansen Date: Mon, 28 Sep 2015 12:18:20 -0700 References: <20150928191817.035A64E2@viggo.jf.intel.com> In-Reply-To: <20150928191817.035A64E2@viggo.jf.intel.com> Message-Id: <20150928191820.BF4CBF05@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Hansen Note: "PK" is how the Intel SDM refers to this bit, so we also use that nomenclature. This only defines the bit, it does not plumb it anywhere to be handled. Signed-off-by: Dave Hansen --- b/arch/x86/mm/fault.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff -puN arch/x86/mm/fault.c~pkeys-05-pfec arch/x86/mm/fault.c --- a/arch/x86/mm/fault.c~pkeys-05-pfec 2015-09-28 11:39:44.073097565 -0700 +++ b/arch/x86/mm/fault.c 2015-09-28 11:39:44.076097701 -0700 @@ -33,6 +33,7 @@ * bit 2 == 0: kernel-mode access 1: user-mode access * bit 3 == 1: use of reserved bit detected * bit 4 == 1: fault was an instruction fetch + * bit 5 == 1: protection keys block access */ enum x86_pf_error_code { @@ -41,6 +42,7 @@ enum x86_pf_error_code { PF_USER = 1 << 2, PF_RSVD = 1 << 3, PF_INSTR = 1 << 4, + PF_PK = 1 << 5, }; /* @@ -916,7 +918,10 @@ static int spurious_fault_check(unsigned if ((error_code & PF_INSTR) && !pte_exec(*pte)) return 0; - + /* + * Note: We do not do lazy flushing on protection key + * changes, so no spurious fault will ever set PF_PK. + */ return 1; } _