Seeing this with Fedora kernel 5.3.0-0.rc1.git3.1.fc31.x86_64 which translates to git bed38c3e2dca
It's causing automated OS installations to hang indefinitely, only on Btrfs. This is an excerpt of the first of many call traces: 15:52:20,316 ERR kernel:INFO: task kworker/u4:0:7 blocked for more than 122 seconds. 15:52:20,316 ERR kernel: Not tainted 5.3.0-0.rc1.git3.1.fc31.x86_64 #1 15:52:20,316 ERR kernel:"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 15:52:20,316 INFO kernel:kworker/u4:0 D12192 7 2 0x80004000 15:52:20,317 INFO kernel:Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs] 15:52:20,317 WARNING kernel:Call Trace: 15:52:20,317 WARNING kernel: ? __schedule+0x352/0x900 15:52:20,317 WARNING kernel: schedule+0x3a/0xb0 15:52:20,317 WARNING kernel: btrfs_tree_read_lock+0xa3/0x260 [btrfs] 15:52:20,317 WARNING kernel: ? finish_wait+0x90/0x90 15:52:20,317 WARNING kernel: btrfs_read_lock_root_node+0x2f/0x40 [btrfs] 15:52:20,317 WARNING kernel: btrfs_search_slot+0x601/0x9d0 [btrfs] 15:52:20,317 WARNING kernel: btrfs_lookup_file_extent+0x4c/0x70 [btrfs] 15:52:20,317 WARNING kernel: __btrfs_drop_extents+0x16e/0xe00 [btrfs] 15:52:20,317 WARNING kernel: ? __set_extent_bit+0x55f/0x6a0 [btrfs] 15:52:20,317 WARNING kernel: ? kmem_cache_free+0x368/0x420 15:52:20,318 WARNING kernel: insert_reserved_file_extent.constprop.0+0x93/0x2e0 [btrfs] 15:52:20,318 WARNING kernel: ? start_transaction+0x95/0x4e0 [btrfs] 15:52:20,318 WARNING kernel: btrfs_finish_ordered_io+0x3da/0x840 [btrfs] 15:52:20,318 WARNING kernel: normal_work_helper+0xd7/0x500 [btrfs] 15:52:20,318 WARNING kernel: process_one_work+0x272/0x5a0 15:52:20,318 WARNING kernel: worker_thread+0x50/0x3b0 15:52:20,318 WARNING kernel: kthread+0x108/0x140 15:52:20,318 WARNING kernel: ? process_one_work+0x5a0/0x5a0 15:52:20,318 WARNING kernel: ? kthread_park+0x80/0x80 15:52:20,318 WARNING kernel: ret_from_fork+0x3a/0x50 15:52:20,318 ERR kernel:INFO: task kworker/u4:1:31 blocked for more than 122 seconds. The full log is here: https://openqa.fedoraproject.org/tests/426671/file/_do_install_and_reboot-syslog -- Chris Murphy
