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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25F96C4332F for ; Fri, 11 Feb 2022 18:53:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236688AbiBKSxb (ORCPT ); Fri, 11 Feb 2022 13:53:31 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:60590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237478AbiBKSx3 (ORCPT ); Fri, 11 Feb 2022 13:53:29 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C9C8CED for ; Fri, 11 Feb 2022 10:53:26 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id C06EBCE2B2C for ; Fri, 11 Feb 2022 18:53:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EEFE5C340F0; Fri, 11 Feb 2022 18:53:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1644605603; bh=EEDi6QcfI/4Fzo+vkKFQeEjbeJOVejiec7/kpPxsLvc=; h=Date:To:From:Subject:From; b=BND2JQd3CnntjBuYdQlBAyZz/y+jg690sYTt5gR/VcfDzh3LLu9TvoRDpRvU97g94 iOC9DlzM4/nmGcwymPovAXujTZz9upzBvFGJS9182WMyI0/6KtILS3/WmdmPoxkpK0 JzJ8H+rqh3krWxXWZaDfR7gvQVJLJ/qqKwX65K4U= Date: Fri, 11 Feb 2022 10:53:22 -0800 To: mm-commits@vger.kernel.org, ziy@nvidia.com, rientjes@google.com, peterx@redhat.com, mike.kravetz@oracle.com, lars.persson@axis.com, kirill.shutemov@linux.intel.com, fam.zheng@bytedance.com, duanxiongchun@bytedance.com, axelrasmussen@google.com, songmuchun@bytedance.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-shmem-fix-missing-cache-flush-in-shmem_mfill_atomic_pte.patch added to -mm tree Message-Id: <20220211185322.EEFE5C340F0@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm: shmem: fix missing cache flush in shmem_mfill_atomic_pte() has been added to the -mm tree. Its filename is mm-shmem-fix-missing-cache-flush-in-shmem_mfill_atomic_pte.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-shmem-fix-missing-cache-flush-in-shmem_mfill_atomic_pte.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-shmem-fix-missing-cache-flush-in-shmem_mfill_atomic_pte.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Muchun Song Subject: mm: shmem: fix missing cache flush in shmem_mfill_atomic_pte() userfaultfd calls shmem_mfill_atomic_pte() which does not do any cache flushing for the target page. Then the target page will be mapped to the user space with a different address (user address), which might have an alias issue with the kernel address used to copy the data from the user to. Insert flush_dcache_page() in non-zero-page case. And replace clear_highpage() with clear_user_highpage() which already considers the cache maintenance. Link: https://lkml.kernel.org/r/20220210123058.79206-6-songmuchun@bytedance.com Fixes: 8d1039634206 ("userfaultfd: shmem: add shmem_mfill_zeropage_pte for userfaultfd support") Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support") Signed-off-by: Muchun Song Cc: Axel Rasmussen Cc: David Rientjes Cc: Fam Zheng Cc: Kirill A. Shutemov Cc: Lars Persson Cc: Mike Kravetz Cc: Peter Xu Cc: Xiongchun Duan Cc: Zi Yan Signed-off-by: Andrew Morton --- --- a/mm/shmem.c~mm-shmem-fix-missing-cache-flush-in-shmem_mfill_atomic_pte +++ a/mm/shmem.c @@ -2357,8 +2357,10 @@ int shmem_mfill_atomic_pte(struct mm_str /* don't free the page */ goto out_unacct_blocks; } + + flush_dcache_page(page); } else { /* ZEROPAGE */ - clear_highpage(page); + clear_user_highpage(page, dst_addr); } } else { page = *pagep; _ Patches currently in -mm which might be from songmuchun@bytedance.com are mm-thp-fix-wrong-cache-flush-in-remove_migration_pmd.patch mm-fix-missing-cache-flush-for-all-tail-pages-of-compound-page.patch mm-hugetlb-fix-missing-cache-flush-in-copy_huge_page_from_user.patch mm-hugetlb-fix-missing-cache-flush-in-hugetlb_mcopy_atomic_pte.patch mm-shmem-fix-missing-cache-flush-in-shmem_mfill_atomic_pte.patch mm-userfaultfd-fix-missing-cache-flush-in-mcopy_atomic_pte-and-__mcopy_atomic.patch mm-replace-multiple-dcache-flush-with-flush_dcache_folio.patch mm-hugetlb-free-the-2nd-vmemmap-page-associated-with-each-hugetlb-page.patch mm-hugetlb-replace-hugetlb_free_vmemmap_enabled-with-a-static_key.patch mm-sparsemem-use-page-table-lock-to-protect-kernel-pmd-operations.patch selftests-vm-add-a-hugetlb-test-case.patch mm-sparsemem-move-vmemmap-related-to-hugetlb-to-config_hugetlb_page_free_vmemmap.patch