Leann, This looks like one for the Kernel team.
Michael On 02/07/2017 01:19 PM, Launchpad Bug Tracker wrote: > bugproxy (bugproxy) has assigned this bug to you for Ubuntu: > > For reference, here is the stack of systemd-udevd seen in the hang: > > [ 1558.214013] INFO: task systemd-udevd:1778 blocked for more than 120 > seconds. > [ 1558.214318] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables > this message. > [ 1558.214556] systemd-udevd D 00003fff8dbdf7a0 0 1778 1 > 0x00040000 > [ 1558.214637] Call Trace: > [ 1558.214673] [c000000004ad3790] [c0000000007aac20] > schedule_timeout+0x180/0x2f0 (unreliable) > [ 1558.214779] [c000000004ad3960] [c0000000000158d0] __switch_to+0x200/0x350 > [ 1558.214870] [c000000004ad39c0] [c0000000007adbb4] __schedule+0x414/0x9e0 > [ 1558.214961] [c000000004ad3a90] [c0000000003b4e54] > blk_mq_freeze_queue_wait+0x64/0xd0 > [ 1558.215107] [c000000004ad3af0] [d000000034011964] > nvme_revalidate_disk+0xd4/0x3a0 [nvme] > [ 1558.215386] [c000000004ad3b90] [c0000000003c2398] > rescan_partitions+0x98/0x390 > [ 1558.215508] [c000000004ad3c60] [c0000000003bb7ac] > __blkdev_reread_part+0x9c/0xd0 > [ 1558.215599] [c000000004ad3c90] [c0000000003bb818] > blkdev_reread_part+0x38/0x70 > [ 1558.215935] [c000000004ad3cc0] [c0000000003bc334] blkdev_ioctl+0x3b4/0xb80 > [ 1558.216016] [c000000004ad3d20] [c0000000002cbcd0] block_ioctl+0x70/0x90 > [ 1558.216114] [c000000004ad3d40] [c000000000296b38] do_vfs_ioctl+0x458/0x740 > [ 1558.216192] [c000000004ad3dd0] [c000000000296ee4] SyS_ioctl+0xc4/0xe0 > [ 1558.216275] [c000000004ad3e30] [c00000000000a17c] system_call+0x38/0xb4 > > It appears that systemd-udevd is triggering every time HTX writes to the > boot sector (partition table) of the raw drive, and this is causing the > revalidate calls which expose the issue with the block driver mq freeze. > With a partition table on each drive, HTX will no longer be writing the > partition table and no longer triggering systemd to re-read the > partition table and try to freeze I/O. > > The fix for this is provided by the following upstream commit: > > 966d2b0 percpu-refcount: fix reference leak during percpu-atomic > transition > > which needs to be pulled into 16.04 (as well as newer releases). > > ** Affects: ubuntu > Importance: Undecided > Assignee: Taco Screen team (taco-screen-team) > Status: New > > > ** Tags: architecture-ppc64le bugnameltc-148242 severity-critical > targetmilestone-inin16042 -- Michael Hohnbaum OIL Program Manager Power (ppc64el) Development Project Manager Canonical, Ltd. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1662673 Title: systemd-udevd hung in blk_mq_freeze_queue_wait testing unpartitioned NVMe drive To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1662673/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs