From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f48.google.com (mail-oi0-f48.google.com [209.85.218.48]) by kanga.kvack.org (Postfix) with ESMTP id A3D426B000D for ; Wed, 6 Jan 2016 19:01:56 -0500 (EST) Received: by mail-oi0-f48.google.com with SMTP id l9so275843726oia.2 for ; Wed, 06 Jan 2016 16:01:56 -0800 (PST) Received: from mga02.intel.com (mga02.intel.com. [134.134.136.20]) by mx.google.com with ESMTP id j9si2363688obw.29.2016.01.06.16.01.17 for ; Wed, 06 Jan 2016 16:01:17 -0800 (PST) Subject: [PATCH 08/31] x86, pkeys: new page fault error code bit: PF_PK From: Dave Hansen Date: Wed, 06 Jan 2016 16:01:16 -0800 References: <20160107000104.1A105322@viggo.jf.intel.com> In-Reply-To: <20160107000104.1A105322@viggo.jf.intel.com> Message-Id: <20160107000116.1A4FFAD4@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 2016-01-06 15:50:06.068176638 -0800 +++ b/arch/x86/mm/fault.c 2016-01-06 15:50:06.071176773 -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