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 376F9C2BBFD for ; Fri, 10 Apr 2020 04:01:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 032B62063A for ; Fri, 10 Apr 2020 04:01:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586491293; bh=KWxq6ZrFrO8jPWH9ZCMnZoxwcvM3QWIjNinxvnDkmIE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=C0vrXUd7BlHovfwDgXTB4830I9vJZMmwjBjZBqnAhdFVEwEp3JBOJZ7olQ72HYIu4 68DEARNYfWfCfDPpIX0IQa0/YScQsMLJJTWOcWTSZ3IB5NdhcdrtzwLPF+Mjognn7z E2GFOgtuNFO7cPiTuTcfoXmekjtj+puoA1jm1msE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727614AbgDJDrb (ORCPT ); Thu, 9 Apr 2020 23:47:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:58338 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726598AbgDJDra (ORCPT ); Thu, 9 Apr 2020 23:47:30 -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 18DFC2145D; Fri, 10 Apr 2020 03:47:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586490450; bh=KWxq6ZrFrO8jPWH9ZCMnZoxwcvM3QWIjNinxvnDkmIE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p9R2Tnb1dF2GpaU4RzRFJZXzXBibCuBSOLrtbfq/BGkBMW5MEf+6c/jYdvgwsSuGJ kRQuPCBN2SqOpglVWSsep+UTVmEO7By5fR9iSxbDcrfI2Be+BKt4C2QNwTgPpbPAFl ozgIXxEhkGn3DMOep+yrXqe7zyfcY8ioVWE0LD/I= 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 5.6 46/68] gfs2: Don't demote a glock until its revokes are written Date: Thu, 9 Apr 2020 23:46:11 -0400 Message-Id: <20200410034634.7731-46-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200410034634.7731-1-sashal@kernel.org> References: <20200410034634.7731-1-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 d0eceaff3cea9..19ebc6cd0f2ba 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -645,6 +645,9 @@ __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