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 E84F1C5518A for ; Wed, 22 Apr 2020 10:52:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC7B62076E for ; Wed, 22 Apr 2020 10:52:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552730; bh=/wQ7uviOaOfZa8i5ALz8UvpYl9DPjVpNJlMKnJyGReE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eMdFapYk5ivJnum1QgQjcO9WFkvnVO8CenzXCmUoOXTg3gJ43QjiPLTJLsaStLdMk tI+EBPoE2S8Z7eJ92ZvV0e4C17fR6nx8dmRiKIfqjiUD8kogef/ekKpE0+EibzsU+C eyvJS3RwHafrbteid9HkgW5RQWECrX80ve9ftKGE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732224AbgDVKwJ (ORCPT ); Wed, 22 Apr 2020 06:52:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:39934 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729046AbgDVKKY (ORCPT ); Wed, 22 Apr 2020 06:10:24 -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 BB7C72075A; Wed, 22 Apr 2020 10:10:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550224; bh=/wQ7uviOaOfZa8i5ALz8UvpYl9DPjVpNJlMKnJyGReE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iIwli34N8IlRK7LreEjrc0jPktMgx0zUQCNZ6FNV3ZlmyxDvml4ho6DA2NJfjF28t OG/2BHPk4AfjEklT0s3wfh30LHFQ2t0yl1SaMnKcgh4Msl03sysRc201cud8Tei5Ro wiexD8xuVRKdIS4EgTNailBYgGEljV3v+Tfued9Y= 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 4.14 018/199] gfs2: Dont demote a glock until its revokes are written Date: Wed, 22 Apr 2020 11:55:44 +0200 Message-Id: <20200422095100.030999389@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095057.806111593@linuxfoundation.org> References: <20200422095057.806111593@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 aea1ed0aebd0f..1e2ff4b32c79a 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