From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f173.google.com (mail-pf0-f173.google.com [209.85.192.173]) by kanga.kvack.org (Postfix) with ESMTP id 65720828DF for ; Fri, 29 Jan 2016 13:17:06 -0500 (EST) Received: by mail-pf0-f173.google.com with SMTP id o185so41173917pfb.1 for ; Fri, 29 Jan 2016 10:17:06 -0800 (PST) Received: from mga11.intel.com (mga11.intel.com. [192.55.52.93]) by mx.google.com with ESMTP id m2si25608901pfj.159.2016.01.29.10.16.54 for ; Fri, 29 Jan 2016 10:16:54 -0800 (PST) Subject: [PATCH 08/31] x86, pkeys: new page fault error code bit: PF_PK From: Dave Hansen Date: Fri, 29 Jan 2016 10:16:54 -0800 References: <20160129181642.98E7D468@viggo.jf.intel.com> In-Reply-To: <20160129181642.98E7D468@viggo.jf.intel.com> Message-Id: <20160129181654.CD3A8A3A@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, torvalds@linux-foundation.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 2016-01-28 15:52:19.775377103 -0800 +++ b/arch/x86/mm/fault.c 2016-01-28 15:52:19.778377241 -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