From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f47.google.com (mail-pa0-f47.google.com [209.85.220.47]) by kanga.kvack.org (Postfix) with ESMTP id 6DB3E6B025A for ; Wed, 16 Sep 2015 13:49:24 -0400 (EDT) Received: by pacex6 with SMTP id ex6so215644716pac.0 for ; Wed, 16 Sep 2015 10:49:24 -0700 (PDT) Received: from mga03.intel.com (mga03.intel.com. [134.134.136.65]) by mx.google.com with ESMTP id tc9si42275497pbc.232.2015.09.16.10.49.09 for ; Wed, 16 Sep 2015 10:49:09 -0700 (PDT) Subject: [PATCH 07/26] x86, pkeys: new page fault error code bit: PF_PK From: Dave Hansen Date: Wed, 16 Sep 2015 10:49:05 -0700 References: <20150916174903.E112E464@viggo.jf.intel.com> In-Reply-To: <20150916174903.E112E464@viggo.jf.intel.com> Message-Id: <20150916174905.E22CA62B@viggo.jf.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: dave@sr71.net Cc: x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org 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. --- 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 2015-09-16 10:48:14.219099976 -0700 +++ b/arch/x86/mm/fault.c 2015-09-16 10:48:14.222100112 -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; } _ -- 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