From patchwork Tue Oct 9 10:19:17 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 10632201 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B2FF113AA for ; Tue, 9 Oct 2018 10:19:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9680F288F1 for ; Tue, 9 Oct 2018 10:19:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8AB672890E; Tue, 9 Oct 2018 10:19:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D7197288F1 for ; Tue, 9 Oct 2018 10:19:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726460AbeJIRfs (ORCPT ); Tue, 9 Oct 2018 13:35:48 -0400 Received: from mx2.suse.de ([195.135.220.15]:36688 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726103AbeJIRfs (ORCPT ); Tue, 9 Oct 2018 13:35:48 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id EE514AEF3; Tue, 9 Oct 2018 10:19:34 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 4C3541E3615; Tue, 9 Oct 2018 12:19:34 +0200 (CEST) From: Jan Kara To: Dan Williams Cc: linux-nvdimm@lists.01.org, , , Jan Kara , stable@vger.kernel.org Subject: [PATCH] mm: Preserve _PAGE_DEVMAP across mprotect() calls Date: Tue, 9 Oct 2018 12:19:17 +0200 Message-Id: <20181009101917.32497-1-jack@suse.cz> X-Mailer: git-send-email 2.16.4 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a result we will see warnings such as: BUG: Bad page map in process JobWrk0013 pte:800001803875ea25 pmd:7624381067 addr:00007f0930720000 vm_flags:280000f9 anon_vma: (null) mapping:ffff97f2384056f0 index:0 file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage: (null) CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G W 4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased) Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018 Call Trace: dump_stack+0x5a/0x75 print_bad_pte+0x217/0x2c0 ? enqueue_task_fair+0x76/0x9f0 _vm_normal_page+0xe5/0x100 zap_pte_range+0x148/0x740 unmap_page_range+0x39a/0x4b0 unmap_vmas+0x42/0x90 unmap_region+0x99/0xf0 ? vma_gap_callbacks_rotate+0x1a/0x20 do_munmap+0x255/0x3a0 vm_munmap+0x54/0x80 SyS_munmap+0x1d/0x30 do_syscall_64+0x74/0x150 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 ... when mprotect(2) gets used on DAX mappings. Also there is a wide variety of other failures that can result from the missing _PAGE_DEVMAP flag when the area gets used by get_user_pages() later. Fix the problem by including _PAGE_DEVMAP in a set of flags that get preserved by mprotect(2). Fixes: 69660fd797c3 ("x86, mm: introduce _PAGE_DEVMAP") Fixes: ebd31197931d ("powerpc/mm: Add devmap support for ppc64") CC: stable@vger.kernel.org Signed-off-by: Jan Kara Acked-by: Michal Hocko Reviewed-by: Johannes Thumshirn --- arch/powerpc/include/asm/book3s/64/pgtable.h | 4 ++-- arch/x86/include/asm/pgtable_types.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 2fdc865ca374..2a2486526d1f 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -114,7 +114,7 @@ */ #define _HPAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \ _PAGE_ACCESSED | H_PAGE_THP_HUGE | _PAGE_PTE | \ - _PAGE_SOFT_DIRTY) + _PAGE_SOFT_DIRTY | _PAGE_DEVMAP) /* * user access blocked by key */ @@ -132,7 +132,7 @@ */ #define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \ _PAGE_ACCESSED | _PAGE_SPECIAL | _PAGE_PTE | \ - _PAGE_SOFT_DIRTY) + _PAGE_SOFT_DIRTY | _PAGE_DEVMAP) #define H_PTE_PKEY (H_PTE_PKEY_BIT0 | H_PTE_PKEY_BIT1 | H_PTE_PKEY_BIT2 | \ H_PTE_PKEY_BIT3 | H_PTE_PKEY_BIT4) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index b64acb08a62b..106b7d0e2dae 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -124,7 +124,7 @@ */ #define _PAGE_CHG_MASK (PTE_PFN_MASK | _PAGE_PCD | _PAGE_PWT | \ _PAGE_SPECIAL | _PAGE_ACCESSED | _PAGE_DIRTY | \ - _PAGE_SOFT_DIRTY) + _PAGE_SOFT_DIRTY | _PAGE_DEVMAP) #define _HPAGE_CHG_MASK (_PAGE_CHG_MASK | _PAGE_PSE) /*