From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 5 Jun 2001 13:51:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 5 Jun 2001 13:51:04 -0400 Received: from mons.uio.no ([129.240.130.14]:48615 "EHLO mons.uio.no") by vger.kernel.org with ESMTP id ; Tue, 5 Jun 2001 13:50:54 -0400 MIME-Version: 1.0 Message-ID: <15133.7158.481243.538585@charged.uio.no> Date: Tue, 5 Jun 2001 19:50:46 +0200 To: Linus Torvalds Cc: Linux Kernel Subject: [PATCH 2.4.5] Fix NFS Oops w.r.t. unhashed inodes X-Mailer: VM 6.89 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Reply-To: trond.myklebust@fys.uio.no From: Trond Myklebust User-Agent: SEMI/1.13.7 (Awazu) CLIME/1.13.6 (=?ISO-2022-JP?B?GyRCQ2YbKEI=?= =?ISO-2022-JP?B?GyRCJU4+MRsoQg==?=) MULE XEmacs/21.1 (patch 14) (Cuyahoga Valley) (i386-redhat-linux) Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi Linus, One consequence of the removal of the 'put_inode: force_delete' made for 2.4.5 mmap() is that we now use the 'magic nfs' codepath in iput(). The result is that when we unhash inodes due to staleness in nfs_revalidate_inode(), we now end up calling clear_inode() in iput without first calling truncate_inode_pages(), and thus trigger the BUG() on line 486 in fs/inode.c. After discussion with Al, I think the minimal solution would be to add a call to truncate_inode_pages() to the magic nfs code. To do the call in nfs_revalidate_inode() itself (Al's suggestion) would be racy w.r.t. adding pages in read or write itself. A second consequence of the removal of force_delete was the fact that file or directory deletion no longer results in the inode getting thrown out of the icache upon last iput(). This gave problems due to inode number reuse on the userland nfsd. The solution is to update i_nlink when we delete or rmdir. Cheers, Trond --- linux-2.4.5-pre6/fs/inode.c.orig Fri May 25 14:15:38 2001 +++ linux-2.4.5-pre6/fs/inode.c Wed May 30 12:17:29 2001 @@ -1044,6 +1044,8 @@ inode->i_state|=I_FREEING; inodes_stat.nr_inodes--; spin_unlock(&inode_lock); + if (inode->i_data.nrpages) + truncate_inode_pages(&inode->i_data, 0); clear_inode(inode); } } --- linux-2.4.5-pre6/fs/nfs/dir.c.orig Fri May 25 14:15:38 2001 +++ linux-2.4.5-pre6/fs/nfs/dir.c Thu May 31 14:53:32 2001 @@ -753,6 +753,8 @@ nfs_zap_caches(dir); error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name); + if (!error) + dentry->d_inode->i_nlink = 0; return error; } @@ -870,6 +872,8 @@ error = NFS_PROTO(dir)->remove(dir, &dentry->d_name); if (error < 0) goto out; + if (inode) + inode->i_nlink--; out_delete: /*