From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f41.google.com (mail-pa0-f41.google.com [209.85.220.41]) by kanga.kvack.org (Postfix) with ESMTP id 9508A6B0260 for ; Mon, 14 Dec 2015 14:06:05 -0500 (EST) Received: by padhk6 with SMTP id hk6so68112042pad.2 for ; Mon, 14 Dec 2015 11:06:05 -0800 (PST) Received: from mga04.intel.com (mga04.intel.com. [192.55.52.120]) by mx.google.com with ESMTP id cj5si10520285pad.65.2015.12.14.11.06.04 for ; Mon, 14 Dec 2015 11:06:04 -0800 (PST) Subject: [PATCH 08/32] x86, pkeys: new page fault error code bit: PF_PK From: Dave Hansen Date: Mon, 14 Dec 2015 11:05:56 -0800 References: <20151214190542.39C4886D@viggo.jf.intel.com> In-Reply-To: <20151214190542.39C4886D@viggo.jf.intel.com> Message-Id: <20151214190556.92FC3386@viggo.jf.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, x86@kernel.org, Dave Hansen , dave.hansen@linux.intel.com 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 Reviewed-by: Thomas Gleixner --- b/arch/x86/mm/fault.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff -puN arch/x86/mm/fault.c~pkeys-05-pfec arch/x86/mm/fault.c --- a/arch/x86/mm/fault.c~pkeys-05-pfec 2015-12-14 10:42:42.240777820 -0800 +++ b/arch/x86/mm/fault.c 2015-12-14 10:42:42.244778000 -0800 @@ -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, }; /* @@ -916,6 +918,12 @@ 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. + */ + if ((error_code & PF_PK)) + return 1; return 1; } _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org