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 B16CDC433F5 for ; Fri, 13 May 2022 22:35:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232133AbiEMWfo (ORCPT ); Fri, 13 May 2022 18:35:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37598 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231667AbiEMWfn (ORCPT ); Fri, 13 May 2022 18:35:43 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8FA813F28 for ; Fri, 13 May 2022 15:35:41 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 8C3A661201 for ; Fri, 13 May 2022 22:35:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2A0DC34100; Fri, 13 May 2022 22:35:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1652481341; bh=zry6QV87PFKj399O2lrWV8a0vaZtAOkXAybfgxNdMJU=; h=Date:To:From:Subject:From; b=ZhaZUqatMiBtBBgjOTR60N6Gu3auQR1KBFpS8ajNGQbLh4u7ZTC1qehuO7wCqajPb quTTrbo2gJjrZsLX+QTZCyyMhdlKJmMQ/CZTV2kTou89ougbNTOIEBomJj5Uy3ha0k F2QqlttMbofMFeC8nTOyOntcgtU8I70lbxKPp5Ro= Date: Fri, 13 May 2022 15:35:40 -0700 To: mm-commits@vger.kernel.org, paulmck@kernel.org, jhubbard@nvidia.com, david@redhat.com, minchan@kernel.org, akpm@linux-foundation.org From: Andrew Morton Subject: [folded-merged] mm-fix-is_pinnable_page-against-on-cma-page-v5.patch removed from -mm tree Message-Id: <20220513223540.E2A0DC34100@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The quilt patch titled Subject: mm-fix-is_pinnable_page-against-on-cma-page-v5 has been removed from the -mm tree. Its filename was mm-fix-is_pinnable_page-against-on-cma-page-v5.patch This patch was dropped because it was folded into mm-fix-is_pinnable_page-against-on-cma-page.patch ------------------------------------------------------ From: Minchan Kim Subject: mm-fix-is_pinnable_page-against-on-cma-page-v5 * clarification why we need READ_ONCE - Paul * Add a comment about READ_ONCE - John Link: https://lkml.kernel.org/r/20220512204143.3961150-1-minchan@kernel.org Signed-off-by: Minchan Kim Cc: "Paul E . McKenney" Cc: John Hubbard Cc: David Hildenbrand Signed-off-by: Andrew Morton --- include/linux/mm.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/include/linux/mm.h~mm-fix-is_pinnable_page-against-on-cma-page-v5 +++ a/include/linux/mm.h @@ -1627,13 +1627,14 @@ static inline bool is_pinnable_page(stru { #ifdef CONFIG_CMA /* - * use volatile to use local variable mt instead of - * refetching mt value. + * Defend against future compiler LTO features, or code refactoring + * that inlines the above function, by forcing a single read. Because, + * this routine races with set_pageblock_migratetype(), and we want to + * avoid reading zero, when actually one or the other flags was set. */ - int __mt = get_pageblock_migratetype(page); int mt = __READ_ONCE(__mt); - if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE) + if (mt & (MIGRATE_CMA | MIGRATE_ISOLATE)) return false; #endif _ Patches currently in -mm which might be from minchan@kernel.org are mm-fix-is_pinnable_page-against-on-cma-page.patch mm-fix-is_pinnable_page-against-on-cma-page-v5-fix.patch mm-dont-be-stuck-to-rmap-lock-on-reclaim-path.patch