From patchwork Sun Jan 30 21:18:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Edgecombe, Rick P" X-Patchwork-Id: 12730137 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48F30C4321E for ; Sun, 30 Jan 2022 21:22:03 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A8F976B007D; Sun, 30 Jan 2022 16:21:53 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 8D2456B0081; Sun, 30 Jan 2022 16:21:53 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6D4696B0082; Sun, 30 Jan 2022 16:21:53 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0192.hostedemail.com [216.40.44.192]) by kanga.kvack.org (Postfix) with ESMTP id 459966B0080 for ; Sun, 30 Jan 2022 16:21:53 -0500 (EST) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 1158D95C9D for ; Sun, 30 Jan 2022 21:21:53 +0000 (UTC) X-FDA: 79088225706.14.1B5D83A Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by imf29.hostedemail.com (Postfix) with ESMTP id 6BF20120005 for ; Sun, 30 Jan 2022 21:21:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643577712; x=1675113712; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=HlWo8OKNThkqHwQn3Dphtl6Opo3L/i/03JpsJVaIZ2A=; b=mVXYgsJQOu2k6FQvh6ltSpU3MIkZSi8nWsBWlA0iZuPkjUvApJ/JMgop rg3HpMiZ5VESr7gLQ3MPmDzUJNliqUpDULbTvLzfMA0+OPjZw6SWUGeJq 7tUheFkcktYTxn7beTAZTr8LTCgiHXsB/KUc7RK+8UO4s9C+cpl8oPhaY 4i3AD5+3WkVwJoiRccnCbg4OI3owr/QTGXqhBTW1ILT9q/bZ8wPx1N1yc EuoKvcxJxH402EGckh0mOwTS3W1K3grAoJDaRfa/82mMwJ7gxiiMzHVLL +dLODeaDpobUtWjz3wuS4eywJKSwUtjxorj56xKGeqzYUXF/Z5BPCx5tu w==; X-IronPort-AV: E=McAfee;i="6200,9189,10243"; a="244970191" X-IronPort-AV: E=Sophos;i="5.88,329,1635231600"; d="scan'208";a="244970191" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jan 2022 13:21:51 -0800 X-IronPort-AV: E=Sophos;i="5.88,329,1635231600"; d="scan'208";a="536856715" Received: from avmallar-mobl1.amr.corp.intel.com (HELO rpedgeco-desk.amr.corp.intel.com) ([10.209.123.171]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jan 2022 13:21:51 -0800 From: Rick Edgecombe To: x86@kernel.org, "H . Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H . J . Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V . Shankar" , Dave Martin , Weijiang Yang , "Kirill A . Shutemov" , joao.moreira@intel.com, John Allen , kcc@google.com, eranian@google.com Cc: rick.p.edgecombe@intel.com, Yu-cheng Yu , Christoph Hellwig Subject: [PATCH 07/35] x86/mm: Remove _PAGE_DIRTY from kernel RO pages Date: Sun, 30 Jan 2022 13:18:10 -0800 Message-Id: <20220130211838.8382-8-rick.p.edgecombe@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220130211838.8382-1-rick.p.edgecombe@intel.com> References: <20220130211838.8382-1-rick.p.edgecombe@intel.com> X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 6BF20120005 X-Stat-Signature: teexhwpeerm3qmszw8io1qpnjmn6ifhe Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=mVXYgsJQ; dmarc=pass (policy=none) header.from=intel.com; spf=none (imf29.hostedemail.com: domain of rick.p.edgecombe@intel.com has no SPF policy when checking 192.55.52.93) smtp.mailfrom=rick.p.edgecombe@intel.com X-Rspam-User: nil X-HE-Tag: 1643577712-851530 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Yu-cheng Yu The x86 family of processors do not directly create read-only and Dirty PTEs. These PTEs are created by software. One such case is that kernel read-only pages are historically setup as Dirty. New processors that support Shadow Stack regard read-only and Dirty PTEs as shadow stack pages. This results in ambiguity between shadow stack and kernel read-only pages. To resolve this, removed Dirty from kernel read- only pages. Signed-off-by: Yu-cheng Yu Reviewed-by: Kirill A. Shutemov Signed-off-by: Rick Edgecombe Cc: "H. Peter Anvin" Cc: Kees Cook Cc: Thomas Gleixner Cc: Dave Hansen Cc: Christoph Hellwig Cc: Andy Lutomirski Cc: Ingo Molnar Cc: Borislav Petkov Cc: Peter Zijlstra --- arch/x86/include/asm/pgtable_types.h | 6 +++--- arch/x86/mm/pat/set_memory.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 40497a9020c6..3781a79b6388 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -190,10 +190,10 @@ enum page_cache_mode { #define _KERNPG_TABLE (__PP|__RW| 0|___A| 0|___D| 0| 0| _ENC) #define _PAGE_TABLE_NOENC (__PP|__RW|_USR|___A| 0|___D| 0| 0) #define _PAGE_TABLE (__PP|__RW|_USR|___A| 0|___D| 0| 0| _ENC) -#define __PAGE_KERNEL_RO (__PP| 0| 0|___A|__NX|___D| 0|___G) -#define __PAGE_KERNEL_ROX (__PP| 0| 0|___A| 0|___D| 0|___G) +#define __PAGE_KERNEL_RO (__PP| 0| 0|___A|__NX| 0| 0|___G) +#define __PAGE_KERNEL_ROX (__PP| 0| 0|___A| 0| 0| 0|___G) #define __PAGE_KERNEL_NOCACHE (__PP|__RW| 0|___A|__NX|___D| 0|___G| __NC) -#define __PAGE_KERNEL_VVAR (__PP| 0|_USR|___A|__NX|___D| 0|___G) +#define __PAGE_KERNEL_VVAR (__PP| 0|_USR|___A|__NX| 0| 0|___G) #define __PAGE_KERNEL_LARGE (__PP|__RW| 0|___A|__NX|___D|_PSE|___G) #define __PAGE_KERNEL_LARGE_EXEC (__PP|__RW| 0|___A| 0|___D|_PSE|___G) #define __PAGE_KERNEL_WP (__PP|__RW| 0|___A|__NX|___D| 0|___G| __WP) diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index b4072115c8ef..844bb30280b7 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1943,7 +1943,7 @@ int set_memory_nx(unsigned long addr, int numpages) int set_memory_ro(unsigned long addr, int numpages) { - return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW), 0); + return change_page_attr_clear(&addr, numpages, __pgprot(_PAGE_RW | _PAGE_DIRTY), 0); } int set_memory_rw(unsigned long addr, int numpages)