On Mon, Nov 13, 2017 at 06:31:39PM +0800, Yu Chen wrote: > Hi all, > Currently we are running hibernation stress test on a server > and unfortunately after 48 rounds of cycling, it fails at a > early stage that, the xfs task refuses to be frozen by the system: > > [ 1934.221653] PM: Syncing filesystems ... > [ 1934.661517] PM: done. > [ 1934.664067] Freezing user space processes ... (elapsed 0.003 seconds) done. > [ 1934.675251] OOM killer disabled. > [ 1934.724317] PM: Preallocating image memory... done (allocated 6906555 pages) > [ 1954.666378] PM: Allocated 27626220 kbytes in 19.93 seconds (1386.16 MB/s) > [ 1954.673939] Freezing remaining freezable tasks ... > [ 1974.681089] Freezing of tasks failed after 20.001 seconds (1 tasks refusing to freeze, wq_busy=0): > [ 1974.691169] xfsaild/dm-1 D 0 1362 2 0x00000080 > [ 1974.697283] Call Trace: > [ 1974.700014] __schedule+0x3be/0x830 > [ 1974.703898] schedule+0x36/0x80 > [ 1974.707440] _xfs_log_force+0x143/0x280 [xfs] > [ 1974.712295] ? schedule_timeout+0x16b/0x350 > [ 1974.716953] ? wake_up_q+0x80/0x80 > [ 1974.720752] ? xfsaild+0x16f/0x770 [xfs] > [ 1974.725134] xfs_log_force+0x2c/0x80 [xfs] > [ 1974.729707] xfsaild+0x16f/0x770 [xfs] > [ 1974.733885] kthread+0x109/0x140 > [ 1974.737480] ? kthread+0x109/0x140 > [ 1974.741271] ? xfs_trans_ail_cursor_first+0x90/0x90 [xfs] > [ 1974.747284] ? kthread_park+0x60/0x60 > [ 1974.751354] ret_from_fork+0x25/0x30 > [ 1974.755366] Restarting kernel threads ... done. > [ 1978.259907] OOM killer enabled. > [ 1978.263405] Restarting tasks ... done. > > The reason for this failure might be that, > while the kernel thread xfsaild/dm-1 is waiting for > xfs-buf/dm-1 to wake it up, however the latter > has already been frozen, thus xfsaild/dm-1 never > has a chance to be woken up and get froze. (Although > the xfsaild/dm-1 remains in TASK_UNINTERRUPTIBLE, which > is quite similar to 'frozen'.) Should be fixed by this commit in the for-next branch: 0bd89676c4fe xfs: check kthread_should_stop() after the setting of task state That should get merged into 4.15 with the next merge... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
