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 X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CDD0C74A35 for ; Wed, 10 Jul 2019 21:32:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E86CA2087F for ; Wed, 10 Jul 2019 21:32:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="MlbQLz+2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727803AbfGJVct (ORCPT ); Wed, 10 Jul 2019 17:32:49 -0400 Received: from mail-pl1-f202.google.com ([209.85.214.202]:35355 "EHLO mail-pl1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725911AbfGJVct (ORCPT ); Wed, 10 Jul 2019 17:32:49 -0400 Received: by mail-pl1-f202.google.com with SMTP id s21so1969008plr.2 for ; Wed, 10 Jul 2019 14:32:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=D4vxIycjAa/oRBETN9HeGCijuet8TadWyyhq7cpzL/s=; b=MlbQLz+2fkGnqHycT99BCVEXFcIhY0NwQnphKHCTU8Gz9tipQo+9WHu51grPurjhXe a2mJ8ImxNmgAbiTIYRG/nSGwe2kz43z1U4ZFd89xe0Qe96E9FIxdd44b8vQ+Qtm9V9b5 HXkWdEoy/bQqkyx07h4E6LUexLwmJCyUDimPcIRIL4qOhQYwmfLIrt3mAISYUmIFbA4S uN7O6+RFujww9gENEH3kpQJwwTNEUg7kBMszggQSnFpNEPgoXxJgqD+B8MPrcpHgxie9 owYX9XCkjhjvjOD8la1tz+HhhRIty/YyOGFWGKeYu2TZ7aDtu9hj+njqVG0AF4Gd16+w Tt2g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=D4vxIycjAa/oRBETN9HeGCijuet8TadWyyhq7cpzL/s=; b=IjmKPkinF4/v/nuKBa3cgfIxgQhERCdCwM3zKepyNMMMz7aeWW2+zeQHLbZGllPu6C Enl32bM3vzkH3Wx56+PIXb6tMQe+zGrfdcyL46axpxjBf1JH8dzWg5OQGKhWi6FL62LN wFo1W8DUg22xcALMj/nDHsejrsTSBVdL31udGdqUh9xTI0EUYcTMyugxOFZixI4zSyFU E265eTHsKRlpKPwlPfw42SRNv5CwLz/OV1HbsMAZTQon4a9Gsk+GdAMKe/TWNazFs6T3 J269E40V05RyAQoyK1UBvnLDy3LGcxH528atuUwcZ7hebHlpQnNNRHSGkD1k46dtyJAJ eJBw== X-Gm-Message-State: APjAAAVUR9iRE2h/opVmRU9lU1U4srkWAt117s99P37AcsSzcMF0Xa2K yi1NWCsjClAvjTGikoltMKKQvlyTWL1RkOcS X-Google-Smtp-Source: APXvYqxkWs1ql8glIONr4J4jL2IwaFcEo5teu2KgnAVys+7+MAYwgY/fHlQzByp8VzJ9+OIkKY/Au1eLlsXi9afg X-Received: by 2002:a65:65c5:: with SMTP id y5mr407700pgv.342.1562794368035; Wed, 10 Jul 2019 14:32:48 -0700 (PDT) Date: Wed, 10 Jul 2019 14:32:38 -0700 Message-Id: <20190710213238.91835-1-henryburns@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.22.0.410.gd8fdbe21b5-goog Subject: [PATCH] mm/z3fold.c: remove z3fold_migration trylock From: Henry Burns To: Vitaly Wool , Andrew Morton Cc: Vitaly Vul , Shakeel Butt , Jonathan Adams , Greg Kroah-Hartman , Snild Dolkow , Thomas Gleixner , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Henry Burns Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org z3fold_page_migrate() will never succeed because it attempts to acquire a lock that has already been taken by migrate.c in __unmap_and_move(). __unmap_and_move() migrate.c trylock_page(oldpage) move_to_new_page(oldpage_newpage) a_ops->migrate_page(oldpage, newpage) z3fold_page_migrate(oldpage, newpage) trylock_page(oldpage) Signed-off-by: Henry Burns --- mm/z3fold.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/mm/z3fold.c b/mm/z3fold.c index 985732c8b025..9fe9330ab8ae 100644 --- a/mm/z3fold.c +++ b/mm/z3fold.c @@ -1335,16 +1335,11 @@ static int z3fold_page_migrate(struct address_space *mapping, struct page *newpa zhdr = page_address(page); pool = zhdr_to_pool(zhdr); - if (!trylock_page(page)) - return -EAGAIN; - if (!z3fold_page_trylock(zhdr)) { - unlock_page(page); return -EAGAIN; } if (zhdr->mapped_count != 0) { z3fold_page_unlock(zhdr); - unlock_page(page); return -EBUSY; } new_zhdr = page_address(newpage); @@ -1376,7 +1371,6 @@ static int z3fold_page_migrate(struct address_space *mapping, struct page *newpa queue_work_on(new_zhdr->cpu, pool->compact_wq, &new_zhdr->work); page_mapcount_reset(page); - unlock_page(page); put_page(page); return 0; } -- 2.22.0.410.gd8fdbe21b5-goog