From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id E94C37DF75 for ; Tue, 10 Jul 2018 22:32:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732697AbeGJWdw (ORCPT ); Tue, 10 Jul 2018 18:33:52 -0400 Received: from mga12.intel.com ([192.55.52.136]:33775 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732461AbeGJWc0 (ORCPT ); Tue, 10 Jul 2018 18:32:26 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Jul 2018 15:31:12 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,335,1526367600"; d="scan'208";a="70305403" Received: from 2b52.sc.intel.com ([143.183.136.52]) by fmsmga004.fm.intel.com with ESMTP; 10 Jul 2018 15:31:12 -0700 From: Yu-cheng Yu 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 , Cyrill Gorcunov , Dave Hansen , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , "Ravi V. Shankar" , Vedvyas Shanbhogue Cc: Yu-cheng Yu Subject: [RFC PATCH v2 11/27] x86/mm: Modify ptep_set_wrprotect and pmdp_set_wrprotect for _PAGE_DIRTY_SW Date: Tue, 10 Jul 2018 15:26:23 -0700 Message-Id: <20180710222639.8241-12-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180710222639.8241-1-yu-cheng.yu@intel.com> References: <20180710222639.8241-1-yu-cheng.yu@intel.com> Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Update ptep_set_wrprotect() and pmdp_set_wrprotect() for _PAGE_DIRTY_SW. Signed-off-by: Yu-cheng Yu --- arch/x86/include/asm/pgtable.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index ecbd3539a864..456a864aa605 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -1170,7 +1170,18 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { + pte_t pte; + clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte); + pte = *ptep; + + /* + * On platforms before CET, other threads could race to + * create a RO and _PAGE_DIRTY_HW PTE again. However, + * on CET platforms, this is safe without a TLB flush. + */ + pte = pte_move_flags(pte, _PAGE_DIRTY_HW, _PAGE_DIRTY_SW); + set_pte_at(mm, addr, ptep, pte); } #define flush_tlb_fix_spurious_fault(vma, address) do { } while (0) @@ -1220,7 +1231,18 @@ static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm, static inline void pmdp_set_wrprotect(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp) { + pmd_t pmd; + clear_bit(_PAGE_BIT_RW, (unsigned long *)pmdp); + pmd = *pmdp; + + /* + * On platforms before CET, other threads could race to + * create a RO and _PAGE_DIRTY_HW PMD again. However, + * on CET platforms, this is safe without a TLB flush. + */ + pmd = pmd_move_flags(pmd, _PAGE_DIRTY_HW, _PAGE_DIRTY_SW); + set_pmd_at(mm, addr, pmdp, pmd); } #define pud_write pud_write -- 2.17.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html