This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed- yakkety' to 'verification-done-yakkety'. If the problem still exists, change the tag 'verification-needed-yakkety' to 'verification-failed- yakkety'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! ** Tags added: verification-needed-yakkety -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1662673 Title: systemd-udevd hung in blk_mq_freeze_queue_wait testing unpartitioned NVMe drive Status in linux package in Ubuntu: Fix Released Status in linux source package in Xenial: Fix Released Status in linux source package in Yakkety: Fix Committed Status in linux source package in Zesty: Fix Released Bug description: 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). To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1662673/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
