From patchwork Fri Jan 24 09:26:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 232812 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 7D536C35242 for ; Fri, 24 Jan 2020 11:42:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 54A5E20678 for ; Fri, 24 Jan 2020 11:42:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579866166; bh=wA66xn8xwT2YRuibEYOeBIITxq2WJ5SmlwKox+m4eYM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=R9I0U3vIOcVuIvqUjgdypOrNSzHPqH5D0yaU6uQQLfV4c6F50GrNaL0owS3mDtfeZ Ov/UdqRoMcDH7ayS1P9JcT4xloHCIOO6otHdr8ub5ewNok6c7qGn/o/qIjcIRikMbX ymeVBsGIsFjF2jwDwXCCN5VcCAw7K0yQNlQ+DZfc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389895AbgAXLLj (ORCPT ); Fri, 24 Jan 2020 06:11:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:47636 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389763AbgAXLLi (ORCPT ); Fri, 24 Jan 2020 06:11:38 -0500 Received: from localhost (ip-213-127-102-57.ip.prioritytelecom.net [213.127.102.57]) (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 DB80B20663; Fri, 24 Jan 2020 11:11:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579864297; bh=wA66xn8xwT2YRuibEYOeBIITxq2WJ5SmlwKox+m4eYM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g7KgrpwuESRUuxR1JJTAjheCxnc3pg6MtRowy613nIqwvt7UTnMZOAO4KrJAfhjaz qGNAWxSee+MUg5L2DkMt9kbXzE4DJvpON3CXNFvafqiyPS9QHRnVjzOIsAyKOuCIrX BbClWGqJzd0ARgLZvvHzCoXln9QM93BJebnMCN0Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Trond Myklebust , Sasha Levin Subject: [PATCH 4.19 227/639] NFS: Fix a soft lockup in the delegation recovery code Date: Fri, 24 Jan 2020 10:26:37 +0100 Message-Id: <20200124093115.321822499@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124093047.008739095@linuxfoundation.org> References: <20200124093047.008739095@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Trond Myklebust [ Upstream commit 6f9449be53f3ce383caed797708b332ede8d952c ] Fix a soft lockup when NFS client delegation recovery is attempted but the inode is in the process of being freed. When the igrab(inode) call fails, and we have to restart the recovery process, we need to ensure that we won't attempt to recover the same delegation again. Fixes: 45870d6909d5a ("NFSv4.1: Test delegation stateids when server...") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin --- fs/nfs/delegation.c | 20 ++++++++++++-------- fs/nfs/delegation.h | 1 + 2 files changed, 13 insertions(+), 8 deletions(-) diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index 74ff459b75efa..b0c0c2fc2fbac 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -240,6 +240,8 @@ static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation spin_lock(&delegation->lock); if (delegation->inode != NULL) inode = igrab(delegation->inode); + if (!inode) + set_bit(NFS_DELEGATION_INODE_FREEING, &delegation->flags); spin_unlock(&delegation->lock); return inode; } @@ -955,10 +957,11 @@ restart: list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { list_for_each_entry_rcu(delegation, &server->delegations, super_list) { - if (test_bit(NFS_DELEGATION_RETURNING, - &delegation->flags)) - continue; - if (test_bit(NFS_DELEGATION_NEED_RECLAIM, + if (test_bit(NFS_DELEGATION_INODE_FREEING, + &delegation->flags) || + test_bit(NFS_DELEGATION_RETURNING, + &delegation->flags) || + test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) == 0) continue; if (!nfs_sb_active(server->super)) @@ -1064,10 +1067,11 @@ restart: list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { list_for_each_entry_rcu(delegation, &server->delegations, super_list) { - if (test_bit(NFS_DELEGATION_RETURNING, - &delegation->flags)) - continue; - if (test_bit(NFS_DELEGATION_TEST_EXPIRED, + if (test_bit(NFS_DELEGATION_INODE_FREEING, + &delegation->flags) || + test_bit(NFS_DELEGATION_RETURNING, + &delegation->flags) || + test_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags) == 0) continue; if (!nfs_sb_active(server->super)) diff --git a/fs/nfs/delegation.h b/fs/nfs/delegation.h index dd0f3eed3890d..f09b153ac82ff 100644 --- a/fs/nfs/delegation.h +++ b/fs/nfs/delegation.h @@ -34,6 +34,7 @@ enum { NFS_DELEGATION_RETURNING, NFS_DELEGATION_REVOKED, NFS_DELEGATION_TEST_EXPIRED, + NFS_DELEGATION_INODE_FREEING, }; int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred,