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 5301CC433EF for ; Fri, 11 Feb 2022 18:53:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236681AbiBKSxa (ORCPT ); Fri, 11 Feb 2022 13:53:30 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:60534 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237105AbiBKSx0 (ORCPT ); Fri, 11 Feb 2022 13:53:26 -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 50D61CFA for ; Fri, 11 Feb 2022 10:53:24 -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 AD26BCE2B2B for ; Fri, 11 Feb 2022 18:53:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4F15C340E9; Fri, 11 Feb 2022 18:53:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1644605601; bh=G+zlA2/ZylxOizrcFHOMNVxikqWGWjuEeWwbvuwnwWw=; h=Date:To:From:Subject:From; b=GBCxfBIAYtTEp7Q1iNTuCm536JwfGR+tbo4vjYAHki7Gq3lsn0EYYYrercskS5kT9 nKP1GejITInvGWOWLQrW7O/od5JXNafJIXxK66uAuMsMF/rMhCGlywl9wVrKJIqVCA dl8sgM9ExtDewlwpvvuHYFT2MzzhQUzAi/qKH3dQ= Date: Fri, 11 Feb 2022 10:53:20 -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-hugetlb-fix-missing-cache-flush-in-hugetlb_mcopy_atomic_pte.patch added to -mm tree Message-Id: <20220211185320.E4F15C340E9@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: hugetlb: fix missing cache flush in hugetlb_mcopy_atomic_pte() has been added to the -mm tree. Its filename is mm-hugetlb-fix-missing-cache-flush-in-hugetlb_mcopy_atomic_pte.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-hugetlb-fix-missing-cache-flush-in-hugetlb_mcopy_atomic_pte.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-hugetlb-fix-missing-cache-flush-in-hugetlb_mcopy_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: hugetlb: fix missing cache flush in hugetlb_mcopy_atomic_pte() folio_copy() will copy the data from one page to the target page, then the target page will be mapped to the user space address, which might have an alias issue with the kernel address used to copy the data from the page to. There are 2 ways to fix this issue. 1) insert flush_dcache_page() after folio_copy(). 2) replace folio_copy() with copy_user_huge_page() which already considers the cache maintenance. We chose 2) way to fix the issue since architectures can optimize this situation. It is also make backports easier. Link: https://lkml.kernel.org/r/20220210123058.79206-5-songmuchun@bytedance.com Fixes: 8cc5fcbb5be8 ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY") Signed-off-by: Muchun Song Reviewed-by: Mike Kravetz Cc: Axel Rasmussen Cc: David Rientjes Cc: Fam Zheng Cc: Kirill A. Shutemov Cc: Lars Persson Cc: Peter Xu Cc: Xiongchun Duan Cc: Zi Yan Signed-off-by: Andrew Morton --- --- a/mm/hugetlb.c~mm-hugetlb-fix-missing-cache-flush-in-hugetlb_mcopy_atomic_pte +++ a/mm/hugetlb.c @@ -5816,7 +5816,8 @@ int hugetlb_mcopy_atomic_pte(struct mm_s *pagep = NULL; goto out; } - folio_copy(page_folio(page), page_folio(*pagep)); + copy_user_huge_page(page, *pagep, dst_addr, dst_vma, + pages_per_huge_page(h)); put_page(*pagep); *pagep = NULL; } _ 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