• Cong Wang's avatar
    nfs: fix kernel warning when removing proc entry · 21e81002
    Cong Wang authored
    I saw the following kernel warning:
    
    [ 1852.321222] ------------[ cut here ]------------
    [ 1852.326527] WARNING: CPU: 0 PID: 118 at fs/proc/generic.c:521 remove_proc_entry+0x154/0x16b()
    [ 1852.335630] remove_proc_entry: removing non-empty directory 'fs/nfsfs', leaking at least 'volumes'
    [ 1852.344084] CPU: 0 PID: 118 Comm: kworker/u8:2 Not tainted 3.16.0+ #540
    [ 1852.350036] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
    [ 1852.354992] Workqueue: netns cleanup_net
    [ 1852.358701]  0000000000000000 ffff880116f2fbd0 ffffffff819c03e9 ffff880116f2fc18
    [ 1852.366474]  ffff880116f2fc08 ffffffff810744ee ffffffff811e0e6e ffff8800d4e96238
    [ 1852.373507]  ffffffff81dbe665 ffff8800d46a5948 0000000000000005 ffff880116f2fc68
    [ 1852.380224] Call Trace:
    [ 1852.381976]  [<ffffffff819c03e9>] dump_stack+0x4d/0x66
    [ 1852.385495]  [<ffffffff810744ee>] warn_slowpath_common+0x7a/0x93
    [ 1852.389869]  [<ffffffff811e0e6e>] ? remove_proc_entry+0x154/0x16b
    [ 1852.393987]  [<ffffffff8107457b>] warn_slowpath_fmt+0x4c/0x4e
    [ 1852.397999]  [<ffffffff811e0e6e>] remove_proc_entry+0x154/0x16b
    [ 1852.402034]  [<ffffffff8129c73d>] nfs_fs_proc_net_exit+0x53/0x56
    [ 1852.406136]  [<ffffffff812a103b>] nfs_net_exit+0x12/0x1d
    [ 1852.409774]  [<ffffffff81785bc9>] ops_exit_list+0x44/0x55
    [ 1852.413529]  [<ffffffff81786389>] cleanup_net+0xee/0x182
    [ 1852.417198]  [<ffffffff81088c9e>] process_one_work+0x209/0x40d
    [ 1852.502320]  [<ffffffff81088bf7>] ? process_one_work+0x162/0x40d
    [ 1852.587629]  [<ffffffff810890c1>] worker_thread+0x1f0/0x2c7
    [ 1852.673291]  [<ffffffff81088ed1>] ? process_scheduled_works+0x2f/0x2f
    [ 1852.759470]  [<ffffffff8108e079>] kthread+0xc9/0xd1
    [ 1852.843099]  [<ffffffff8109427f>] ? finish_task_switch+0x3a/0xce
    [ 1852.926518]  [<ffffffff8108dfb0>] ? __kthread_parkme+0x61/0x61
    [ 1853.008565]  [<ffffffff819cbeac>] ret_from_fork+0x7c/0xb0
    [ 1853.076477]  [<ffffffff8108dfb0>] ? __kthread_parkme+0x61/0x61
    [ 1853.140653] ---[ end trace 69c4c6617f78e32d ]---
    
    It looks wrong that we add "/proc/net/nfsfs" in nfs_fs_proc_net_init()
    while remove "/proc/fs/nfsfs" in nfs_fs_proc_net_exit().
    
    Fixes: commit 65b38851 (NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes)
    Cc: Eric W. Biederman <ebiederm@xmission.com>
    Cc: Trond Myklebust <trond.myklebust@primarydata.com>
    Cc: Dan Aloni <dan@kernelim.com>
    Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
    [Trond: replace uses of remove_proc_entry() with remove_proc_subtree()
    as suggested by Al Viro]
    Cc: stable@vger.kernel.org # 3.4.x : 65b38851: NFS: Fix /proc/fs/nfsfs/servers
    Cc: stable@vger.kernel.org # 3.4.x
    Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
    21e81002
client.c 37.4 KB