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 BFD14C4321E for ; Tue, 8 Feb 2022 22:29:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1387684AbiBHW0G (ORCPT ); Tue, 8 Feb 2022 17:26:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1386826AbiBHVP6 (ORCPT ); Tue, 8 Feb 2022 16:15:58 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DBADBC0612B8 for ; Tue, 8 Feb 2022 13:15:57 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 7A10961573 for ; Tue, 8 Feb 2022 21:15:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD4F5C004E1; Tue, 8 Feb 2022 21:15:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1644354956; bh=R1eCsiwkj6jCaveJDtZUhEWMeABfVa3/HHu6x/VP7eQ=; h=Date:To:From:Subject:From; b=SXM6L/3KY5L+r48m0pg6FSKgX9xMONZ4PCHKmImof43eQXwtvS5DL4ZLnfkRhe/9P reL+NmJRVB7UTXVdNzMU7cEfrQHIAnW6haZAI/H5xgvZjX3WVeIwrPmaWIarWTKayb m+csJsVLuDw8+q/fAcMKBe7XiR21zI+Ti85p0oF8= Date: Tue, 08 Feb 2022 13:15:56 -0800 To: mm-commits@vger.kernel.org, ziy@nvidia.com, willy@infradead.org, rientjes@google.com, mike.kravetz@oracle.com, lars.persson@axis.com, kirill.shutemov@linux.intel.com, duanxiongchun@bytedance.com, almasrymina@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: <20220208211556.CD4F5C004E1@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) to fix the issue since architectures can optimize this situation. Link: https://lkml.kernel.org/r/20220208073617.70342-5-songmuchun@bytedance.com Fixes: 8cc5fcbb5be8 ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY") Signed-off-by: Muchun Song Cc: David Rientjes Cc: Kirill A. Shutemov Cc: Lars Persson Cc: Matthew Wilcox Cc: Mike Kravetz Cc: Mina Almasry Cc: Xiongchun Duan Cc: Zi Yan Signed-off-by: Andrew Morton --- mm/hugetlb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/hugetlb.c~mm-hugetlb-fix-missing-cache-flush-in-hugetlb_mcopy_atomic_pte +++ a/mm/hugetlb.c @@ -5817,7 +5817,8 @@ 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-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