On Mon, 8 Jan 2007 08:37:34 +1100 David Chinner <[EMAIL PROTECTED]> wrote:
> On Thu, Jan 04, 2007 at 02:14:21AM +0200, Sami Farin wrote: > > just a simple test I did... > > xfs_freeze -f /mnt/newtest > > cp /etc/fstab /mnt/newtest > > xfs_freeze -u /mnt/newtest > > > > 2007-01-04 01:44:30.341979500 <4>BUG: warning at > > kernel/mutex-debug.c:80/debug_mutex_unlock() > > 2007-01-04 01:44:30.385771500 <4> [<c0103cfb>] dump_trace+0x215/0x21a > > 2007-01-04 01:44:30.385774500 <4> [<c0103da3>] show_trace_log_lvl+0x1a/0x30 > > 2007-01-04 01:44:30.385775500 <4> [<c0103dcb>] show_trace+0x12/0x14 > > 2007-01-04 01:44:30.385777500 <4> [<c0103ec8>] dump_stack+0x19/0x1b > > 2007-01-04 01:44:30.385778500 <4> [<c013a3af>] debug_mutex_unlock+0x69/0x120 > > 2007-01-04 01:44:30.385779500 <4> [<c04b4aac>] > > __mutex_unlock_slowpath+0x44/0xf0 > > 2007-01-04 01:44:30.385780500 <4> [<c04b4887>] mutex_unlock+0x8/0xa > > 2007-01-04 01:44:30.385782500 <4> [<c018d0ba>] thaw_bdev+0x57/0x6e > > 2007-01-04 01:44:30.385791500 <4> [<c026a6cf>] xfs_ioctl+0x7ce/0x7d3 > > 2007-01-04 01:44:30.385793500 <4> [<c0269158>] xfs_file_ioctl+0x33/0x54 > > 2007-01-04 01:44:30.385794500 <4> [<c01793f2>] do_ioctl+0x76/0x85 > > 2007-01-04 01:44:30.385795500 <4> [<c0179570>] vfs_ioctl+0x59/0x1aa > > 2007-01-04 01:44:30.385796500 <4> [<c0179728>] sys_ioctl+0x67/0x77 > > 2007-01-04 01:44:30.385797500 <4> [<c0102e73>] syscall_call+0x7/0xb > > 2007-01-04 01:44:30.385799500 <4> [<001be410>] 0x1be410 > > 2007-01-04 01:44:30.385800500 <4> ======================= > > > > fstab was there just fine after -u. > > Oh, that still hasn't been fixed? Generic bug, not XFS - the global > semaphore->mutex cleanup converted the bd_mount_sem to a mutex, and > mutexes complain loudly when a the process unlocking the mutex is > not the process that locked it. > > Basically, the generic code is broken - the bd_mount_mutex needs to > be reverted back to a semaphore because it is locked and unlocked > by different processes. The following patch does this.... > > ... > > Revert bd_mount_mutex back to a semaphore so that xfs_freeze -f /mnt/newtest; > xfs_freeze -u /mnt/newtest works safely and doesn't produce lockdep warnings. Sad. The alternative would be to implement mutex_unlock_dont_warn_if_a_different_task_did_it(). Ingo? Possible? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
