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 C8519C2BB1D for ; Fri, 10 Apr 2020 03:52:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 971FB20936 for ; Fri, 10 Apr 2020 03:52:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586490743; bh=69OB8wXKOxwKkXELlIwaMk0gi4EzRqKoBvI16VoEw8s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NU9slEPA89AsYuW0oSmqGggz9WQMZz+eDGO/4fKdwrGmjDAhG+FLQn7C9YjUYD0aP Si/Z6cP0Qp0CZS1+c3x+nJH4eSs2gNKnKkS4JeaOVhbasuJGLkFqX7kdFjFYyhTFuT GhU///iOZkHCfW5MijIuTJhpZ7r23zbP/Q6uQgIQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726752AbgDJDwP (ORCPT ); Thu, 9 Apr 2020 23:52:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:36382 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728506AbgDJDvQ (ORCPT ); Thu, 9 Apr 2020 23:51:16 -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 40CB4215A4; Fri, 10 Apr 2020 03:51:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586490676; bh=69OB8wXKOxwKkXELlIwaMk0gi4EzRqKoBvI16VoEw8s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iWZgPkAuwWdwqRyI9SDQvy4Wi/rFmfUp3nZuhdqeLFafFfP/R/FgeRkCrWJvHV1Ii 2Yhb9JBZEQ5PXwx/85BpGCZEbTP/5an9TojFL5AEIpA6Gxu5aRumoHJdaDbLEv3Aj5 pQrYjyEF3Ve+5xpkbPWuBVpmGAbpo6POLdL/Ru3c= 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 4.9 5/9] gfs2: Don't demote a glock until its revokes are written Date: Thu, 9 Apr 2020 23:51:06 -0400 Message-Id: <20200410035111.9938-5-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200410035111.9938-1-sashal@kernel.org> References: <20200410035111.9938-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 efd44d5645d83..adc1a97cfe96d 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -548,6 +548,9 @@ __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