lkml.org 
[lkml]   [2007]   [Sep]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Subjectlockdep wierdness...
    From
    Date
    I'm seeing lockdep warning about a potential lock inversion between
    &mm->mmap_sem and &inode->i_mutex in NFS (see attachment).

    Unfortunately the basis for the warning appears to be the behaviour in
    ext3(???). AFAICS there is no way for NFS to share an inode->i_mutex
    with ext3. What to do?

    Trond
    =======================================================
    [ INFO: possible circular locking dependency detected ]
    2.6.23-rc7-g8809e921 #1
    -------------------------------------------------------
    beagle-build-in/24375 is trying to acquire lock:
    (&mm->mmap_sem){----}, at: [<c05a2887>] do_page_fault+0x17d/0x591

    but task is already holding lock:
    (&inode->i_mutex){--..}, at: [<c059f9e3>] mutex_lock+0x1c/0x1f

    which lock already depends on the new lock.


    the existing dependency chain (in reverse order) is:

    -> #1 (&inode->i_mutex){--..}:
    [<c043d4da>] __lock_acquire+0x9f3/0xba6
    [<c043da62>] lock_acquire+0x5f/0x78
    [<c059f832>] __mutex_lock_slowpath+0xe5/0x27a
    [<c059f9e3>] mutex_lock+0x1c/0x1f
    [<f8c92495>] nfs_revalidate_mapping+0x64/0x9c [nfs]
    [<f8c8ff2a>] nfs_file_mmap+0x46/0x75 [nfs]
    [<c046097c>] mmap_region+0x1ea/0x3b8
    [<c0460e9b>] do_mmap_pgoff+0x27b/0x2da
    [<c0407d77>] sys_mmap2+0x9b/0xb5
    [<c040405e>] sysenter_past_esp+0x5f/0x99
    [<ffffffff>] 0xffffffff

    -> #0 (&mm->mmap_sem){----}:
    [<c043d3c6>] __lock_acquire+0x8df/0xba6
    [<c043da62>] lock_acquire+0x5f/0x78
    [<c04360db>] down_read+0x3a/0x4c
    [<c05a2887>] do_page_fault+0x17d/0x591
    [<c05a1382>] error_code+0x72/0x78
    [<f88acaac>] call_filldir+0xac/0xc3 [ext3]
    [<f88acdb2>] ext3_readdir+0x217/0x5e5 [ext3]
    [<c04798a1>] vfs_readdir+0x67/0x93
    [<c0479af6>] sys_getdents+0x5f/0x9d
    [<c040405e>] sysenter_past_esp+0x5f/0x99
    [<ffffffff>] 0xffffffff

    other info that might help us debug this:

    1 lock held by beagle-build-in/24375:
    #0: (&inode->i_mutex){--..}, at: [<c059f9e3>] mutex_lock+0x1c/0x1f

    stack backtrace:
    [<c04050ee>] show_trace_log_lvl+0x1a/0x2f
    [<c0405b58>] show_trace+0x12/0x14
    [<c0405b70>] dump_stack+0x16/0x18
    [<c043bc05>] print_circular_bug_tail+0x5f/0x68
    [<c043d3c6>] __lock_acquire+0x8df/0xba6
    [<c043da62>] lock_acquire+0x5f/0x78
    [<c04360db>] down_read+0x3a/0x4c
    [<c05a2887>] do_page_fault+0x17d/0x591
    [<c05a1382>] error_code+0x72/0x78
    [<f88acaac>] call_filldir+0xac/0xc3 [ext3]
    [<f88acdb2>] ext3_readdir+0x217/0x5e5 [ext3]
    [<c04798a1>] vfs_readdir+0x67/0x93
    [<c0479af6>] sys_getdents+0x5f/0x9d
    [<c040405e>] sysenter_past_esp+0x5f/0x99
    =======================
    \
     
     \ /
      Last update: 2007-09-25 00:11    [W:0.025 / U:63.204 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site