===================================== WARNING: bad unlock balance detected! 4.19.0-rc6+ #262 Not tainted ------------------------------------- kobject: 'kvm' (00000000ffd86dc9): kobject_uevent_env kworker/u4:1/23 is trying to release lock (&file->mut) at: [] ucma_event_handler+0x788/0xff0 drivers/infiniband/core/ucma.c:392 but there are no more locks to release! kobject: 'kvm' (00000000ffd86dc9): fill_kobj_path: path = '/devices/virtual/misc/kvm' other info that might help us debug this: 4 locks held by kworker/u4:1/23: #0: 0000000081483615 ((wq_completion)"ib_addr"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: 0000000081483615 ((wq_completion)"ib_addr"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 0000000081483615 ((wq_completion)"ib_addr"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 0000000081483615 ((wq_completion)"ib_addr"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 0000000081483615 ((wq_completion)"ib_addr"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 0000000081483615 ((wq_completion)"ib_addr"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 0000000081483615 ((wq_completion)"ib_addr"){+.+.}, at: process_one_work+0xb43/0x1b90 kernel/workqueue.c:2124 #1: 00000000ad56ebc0 ((work_completion)(&(&req->work)->work)){+.+.}, at: process_one_work+0xb9a/0x1b90 kernel/workqueue.c:2128 #2: 0000000095025eb3 (&id_priv->handler_mutex){+.+.}, at: addr_handler+0xed/0x430 drivers/infiniband/core/cma.c:2858 #3: kobject: 'loop5' (000000000c892b23): kobject_uevent_env 0000000067e65ac7 kobject: 'loop5' (000000000c892b23): fill_kobj_path: path = '/devices/virtual/block/loop5' (&file->mut){+.+.}, at: ucma_event_handler+0x116/0xff0 drivers/infiniband/core/ucma.c:352 stack backtrace: CPU: 1 PID: 23 Comm: kworker/u4:1 Not tainted 4.19.0-rc6+ #262 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: ib_addr process_one_req Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 print_unlock_imbalance_bug.cold.48+0xcc/0xd8 kernel/locking/lockdep.c:3464 __lock_release kernel/locking/lockdep.c:3671 [inline] lock_release+0x785/0x970 kernel/locking/lockdep.c:3919 __mutex_unlock_slowpath+0x102/0x8c0 kernel/locking/mutex.c:1197 mutex_unlock+0xd/0x10 kernel/locking/mutex.c:713 ucma_event_handler+0x788/0xff0 drivers/infiniband/core/ucma.c:392 addr_handler+0x311/0x430 drivers/infiniband/core/cma.c:2882 kobject: 'loop2' (0000000093c10b48): kobject_uevent_env process_one_req+0x1a6/0x940 drivers/infiniband/core/addr.c:570 kobject: 'loop2' (0000000093c10b48): fill_kobj_path: path = '/devices/virtual/block/loop2' process_one_work+0xc90/0x1b90 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413