From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B209C3F68F for ; Wed, 5 Feb 2020 18:21:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DEF0C24125 for ; Wed, 5 Feb 2020 18:21:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727793AbgBESVs (ORCPT ); Wed, 5 Feb 2020 13:21:48 -0500 Received: from mga14.intel.com ([192.55.52.115]:20934 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727799AbgBESU3 (ORCPT ); Wed, 5 Feb 2020 13:20:29 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Feb 2020 10:20:28 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,406,1574150400"; d="scan'208";a="279447806" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by FMSMGA003.fm.intel.com with ESMTP; 05 Feb 2020 10:20:27 -0800 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 , 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" , Vedvyas Shanbhogue , Dave Martin , x86-patch-review@intel.com Cc: Yu-cheng Yu Subject: [RFC PATCH v9 15/27] mm: Handle THP/HugeTLB Shadow Stack page fault Date: Wed, 5 Feb 2020 10:19:23 -0800 Message-Id: <20200205181935.3712-16-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20200205181935.3712-1-yu-cheng.yu@intel.com> References: <20200205181935.3712-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org This patch implements THP Shadow Stack (SHSTK) copying in the same way as in the previous patch for regular PTE. In copy_huge_pmd(), clear the dirty bit from the PMD to cause a page fault upon the next SHSTK access to the PMD. At that time, fix the PMD and copy/re-use the page. Signed-off-by: Yu-cheng Yu --- arch/x86/mm/pgtable.c | 8 ++++++++ include/asm-generic/pgtable.h | 11 +++++++++++ mm/huge_memory.c | 4 ++++ 3 files changed, 23 insertions(+) diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 2eb33794c08d..3340b1d4e9da 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -886,4 +886,12 @@ inline pte_t pte_set_vma_features(pte_t pte, struct vm_area_struct *vma) else return pte; } + +inline pmd_t pmd_set_vma_features(pmd_t pmd, struct vm_area_struct *vma) +{ + if (vma->vm_flags & VM_SHSTK) + return pmd_mkdirty_shstk(pmd); + else + return pmd; +} #endif /* CONFIG_X86_INTEL_SHADOW_STACK_USER */ diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 9cb2f9ba5895..a9df093fdf45 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -1201,9 +1201,20 @@ static inline pte_t pte_set_vma_features(pte_t pte, struct vm_area_struct *vma) { return pte; } + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static inline pmd_t pmd_set_vma_features(pmd_t pmd, struct vm_area_struct *vma) +{ + return pmd; +} +#endif #else bool arch_copy_pte_mapping(vm_flags_t vm_flags); pte_t pte_set_vma_features(pte_t pte, struct vm_area_struct *vma); + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +pmd_t pmd_set_vma_features(pmd_t pmd, struct vm_area_struct *vma); +#endif #endif #endif /* CONFIG_MMU */ diff --git a/mm/huge_memory.c b/mm/huge_memory.c index a88093213674..93ef368df2dd 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -636,6 +636,7 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, entry = mk_huge_pmd(page, vma->vm_page_prot); entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); + entry = pmd_set_vma_features(entry, vma); page_add_new_anon_rmap(page, vma, haddr, true); mem_cgroup_commit_charge(page, memcg, false, true); lru_cache_add_active_or_unevictable(page, vma); @@ -1278,6 +1279,7 @@ static vm_fault_t do_huge_pmd_wp_page_fallback(struct vm_fault *vmf, pte_t entry; entry = mk_pte(pages[i], vma->vm_page_prot); entry = maybe_mkwrite(pte_mkdirty(entry), vma); + entry = pte_set_vma_features(entry, vma); memcg = (void *)page_private(pages[i]); set_page_private(pages[i], 0); page_add_new_anon_rmap(pages[i], vmf->vma, haddr, false); @@ -1360,6 +1362,7 @@ vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd) pmd_t entry; entry = pmd_mkyoung(orig_pmd); entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); + entry = pmd_set_vma_features(entry, vma); if (pmdp_set_access_flags(vma, haddr, vmf->pmd, entry, 1)) update_mmu_cache_pmd(vma, vmf->address, vmf->pmd); ret |= VM_FAULT_WRITE; @@ -1432,6 +1435,7 @@ vm_fault_t do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd) pmd_t entry; entry = mk_huge_pmd(new_page, vma->vm_page_prot); entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); + entry = pmd_set_vma_features(entry, vma); pmdp_huge_clear_flush_notify(vma, haddr, vmf->pmd); page_add_new_anon_rmap(new_page, vma, haddr, true); mem_cgroup_commit_charge(new_page, memcg, false, true); -- 2.21.0