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 A29F8C433F5 for ; Fri, 13 May 2022 08:54:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344569AbiEMIyx (ORCPT ); Fri, 13 May 2022 04:54:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378669AbiEMIyv (ORCPT ); Fri, 13 May 2022 04:54:51 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4A2B92B274D for ; Fri, 13 May 2022 01:54:47 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id E9F9DB82CA1 for ; Fri, 13 May 2022 08:54:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 518B5C34100; Fri, 13 May 2022 08:54:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652432084; bh=V3T7/15u4mqxUZuvZfYnhnQn63PZp4pSyNwewfez5/A=; h=Subject:To:Cc:From:Date:From; b=2YNll0koRWiIR9jsUoi1wFnY1E1urS//kR06+2+UHaHcAwpYAYysU6RaSw89g1deE XWEjNOmeDIUmCKzbF1rjlfqSesX1a/LK4XRNpuL9Gg8ZXDzboWInTBLfJbVMHHzW17 xu/S4ZkYza1MuKgSlvpdF94dxjRLEYk2hImU6CZ8= Subject: FAILED: patch "[PATCH] mm: fix missing cache flush for all tail pages of compound" failed to apply to 4.19-stable tree To: songmuchun@bytedance.com, akpm@linux-foundation.org, axelrasmussen@google.com, duanxiongchun@bytedance.com, fam.zheng@bytedance.com, kirill.shutemov@linux.intel.com, lars.persson@axis.com, mike.kravetz@oracle.com, peterx@redhat.com, rientjes@google.com, torvalds@linux-foundation.org, ziy@nvidia.com Cc: From: Date: Fri, 13 May 2022 10:54:31 +0200 Message-ID: <1652432071173175@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 2771739a7162782c0aa6424b2e3dd874e884a15d Mon Sep 17 00:00:00 2001 From: Muchun Song Date: Tue, 22 Mar 2022 14:41:56 -0700 Subject: [PATCH] mm: fix missing cache flush for all tail pages of compound page The D-cache maintenance inside move_to_new_page() only consider one page, there is still D-cache maintenance issue for tail pages of compound page (e.g. THP or HugeTLB). THP migration is only enabled on x86_64, ARM64 and powerpc, while powerpc and arm64 need to maintain the consistency between I-Cache and D-Cache, which depends on flush_dcache_page() to maintain the consistency between I-Cache and D-Cache. But there is no issues on arm64 and powerpc since they already considers the compound page cache flushing in their icache flush function. HugeTLB migration is enabled on arm, arm64, mips, parisc, powerpc, riscv, s390 and sh, while arm has handled the compound page cache flush in flush_dcache_page(), but most others do not. In theory, the issue exists on many architectures. Fix this by not using flush_dcache_folio() since it is not backportable. Link: https://lkml.kernel.org/r/20220210123058.79206-3-songmuchun@bytedance.com Fixes: 290408d4a250 ("hugetlb: hugepage migration core") Signed-off-by: Muchun Song Reviewed-by: Zi Yan 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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds diff --git a/mm/migrate.c b/mm/migrate.c index be0d5ae36dc1..996c0e386734 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -916,9 +916,12 @@ static int move_to_new_page(struct page *newpage, struct page *page, if (!PageMappingFlags(page)) page->mapping = NULL; - if (likely(!is_zone_device_page(newpage))) - flush_dcache_page(newpage); + if (likely(!is_zone_device_page(newpage))) { + int i, nr = compound_nr(newpage); + for (i = 0; i < nr; i++) + flush_dcache_page(newpage + i); + } } out: return rc;