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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 75BFBC352BE for ; Thu, 16 Apr 2020 14:09:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4AB62206D6 for ; Thu, 16 Apr 2020 14:09:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587046157; bh=5wLauErA2sXj1hwEOBTS/RNcaB9yDT/S+WliV8V9x+Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2iHscgjxOA3mCVOGp5ZBcyRmUE8dbtZHbIc+83epQPX9j9OOZ+P+bgjd9STOIksNX wrnOc7itU+/1AMtClZRwdVZp25rTREJC8DJl9nlsbyP01lGmEINzNnTE3c2u2DJh1e 3tXHgg85C1nxWQ8RaOpwle1zFI0GrwVIUhM/HKgw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393301AbgDPOJE (ORCPT ); Thu, 16 Apr 2020 10:09:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:59796 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2898547AbgDPNqD (ORCPT ); Thu, 16 Apr 2020 09:46:03 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F1C2121734; Thu, 16 Apr 2020 13:46:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587044762; bh=5wLauErA2sXj1hwEOBTS/RNcaB9yDT/S+WliV8V9x+Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bkdf5f3a61ejWhul7IBtRdPDOtbXRMK7Yz6nuZ7tcckZeDxdYKZlf1tb9m0lpc5+m 9u9LW+7txWC+twzTrOMi2aJlYNhN3pbwJ6e8jtN3z6iVXhHt8CVr4NjbQhDXRyF/Dw ESFKSTpdjFRLN1e5IcRhMRRumDUge+rCGpnQXvGE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Bob Peterson , Andreas Gruenbacher , Sasha Levin Subject: [PATCH 5.4 051/232] gfs2: Dont demote a glock until its revokes are written Date: Thu, 16 Apr 2020 15:22:25 +0200 Message-Id: <20200416131322.069893844@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200416131316.640996080@linuxfoundation.org> References: <20200416131316.640996080@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 0290a22ebccf5..21820a5b388fd 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -639,6 +639,9 @@ __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