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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 19DB9C2D0EC for ; Fri, 10 Apr 2020 03:54:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D5C532063A for ; Fri, 10 Apr 2020 03:54:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586490864; bh=JVBQ4mJiai4SFGqM9hpLiYzHjPgT+kxE4i+UwDn0DQY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1FoLxAJeTRQCh8jkYBXi7YMQD4uvJoD+5OgWrNg0PNf1RlylCQLQBYYUsxS1itqqM TjyhlCNyalyOgdhkX8flcvlh1pOeD9njd9soPVkWY+kP7lVMUwO1uL7oJAWIxTsx4g r0V55N3E07QHY0Qf6VInLLqWTzV7oSEY1fNgHZJk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728899AbgDJDyX (ORCPT ); Thu, 9 Apr 2020 23:54:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:34994 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728888AbgDJDuZ (ORCPT ); Thu, 9 Apr 2020 23:50:25 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1ADC221655; Fri, 10 Apr 2020 03:50:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586490625; bh=JVBQ4mJiai4SFGqM9hpLiYzHjPgT+kxE4i+UwDn0DQY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2q7Piw78gdro0AS5pTvf6QO1LwvBpXxNHLgxJdbC/KrTSBDhj9GUh+/XMuFUjj+xu hBO4X9GLvjBJLbcCToPH9qfj5Ajp+TlC2TrYmX+ZQNnsI+8vT+TdEBnQ80fAgzEvND vOwV8W5ApRUEAP52QFwmwiR0GwOpD9mAvZJjmpqQ= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Bob Peterson , Andreas Gruenbacher , Sasha Levin , cluster-devel@redhat.com Subject: [PATCH AUTOSEL 4.19 17/32] gfs2: Don't demote a glock until its revokes are written Date: Thu, 9 Apr 2020 23:49:50 -0400 Message-Id: <20200410035005.9371-17-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200410035005.9371-1-sashal@kernel.org> References: <20200410035005.9371-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Bob Peterson [ Upstream commit df5db5f9ee112e76b5202fbc331f990a0fc316d6 ] Before this patch, run_queue would demote glocks based on whether there are any more holders. But if the glock has pending revokes that haven't been written to the media, giving up the glock might end in file system corruption if the revokes never get written due to io errors, node crashes and fences, etc. In that case, another node will replay the metadata blocks associated with the glock, but because the revoke was never written, it could replay that block even though the glock had since been granted to another node who might have made changes. This patch changes the logic in run_queue so that it never demotes a glock until its count of pending revokes reaches zero. Signed-off-by: Bob Peterson Reviewed-by: Andreas Gruenbacher Signed-off-by: Sasha Levin --- fs/gfs2/glock.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index ccdd8c821abd7..f8a5eef3d014b 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -636,6 +636,9 @@ __acquires(&gl->gl_lockref.lock) goto out_unlock; if (nonblock) goto out_sched; + smp_mb(); + if (atomic_read(&gl->gl_revokes) != 0) + goto out_sched; set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE); gl->gl_target = gl->gl_demote_state; -- 2.20.1