INFO: task kworker/u4:1:136 blocked for more than 143 seconds. Not tainted 5.15.186-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:1 state:D stack: 0 pid: 136 ppid: 2 flags:0x00000008 Workqueue: writeback wb_workfn (flush-7:0) Call trace: __switch_to+0x2f4/0x558 arch/arm64/kernel/process.c:521 context_switch kernel/sched/core.c:5030 [inline] __schedule+0xe00/0x1c0c kernel/sched/core.c:6376 schedule+0x11c/0x1c8 kernel/sched/core.c:6459 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6518 __mutex_lock_common+0xa9c/0x1edc kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0xac/0x11c kernel/locking/mutex.c:743 jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 jfs_write_inode+0x128/0x1f8 fs/jfs/inode.c:132 write_inode fs/fs-writeback.c:1495 [inline] __writeback_single_inode+0x560/0x11f0 fs/fs-writeback.c:1705 writeback_sb_inodes+0x7fc/0x1378 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x110/0x394 fs/fs-writeback.c:2001 wb_writeback+0x3ec/0xe44 fs/fs-writeback.c:2106 wb_check_background_flush fs/fs-writeback.c:2172 [inline] wb_do_writeback fs/fs-writeback.c:2260 [inline] wb_workfn+0xa7c/0xdd8 fs/fs-writeback.c:2288 process_one_work+0x79c/0x1140 kernel/workqueue.c:2310 worker_thread+0x8f4/0x101c kernel/workqueue.c:2457 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:855 Showing all locks held in the system: 4 locks held by kworker/u4:0/9: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff80001b2f7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000ce1c20e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000e72d70c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 1 lock held by khungtaskd/27: #0: ffff800014351360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311 4 locks held by kworker/u4:1/136: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff80001b947c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000daf4a0e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000e72d3008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 4 locks held by kworker/u4:3/302: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff80001f2c7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000c13ba0e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000ee453948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 4 locks held by kworker/u4:4/367: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff80001f687c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000cfea00e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000e73cb008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 2 locks held by getty/3807: #0: ffff0000d44b6098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340 #1: ffff80001b7c62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2f0/0xf6c drivers/tty/n_tty.c:2158 4 locks held by kworker/u4:5/4096: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff80001b857c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000d87c80e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000ee4c81c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 4 locks held by kworker/u4:6/4097: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff80001f437c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000ebefc0e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000e73cf0c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 4 locks held by syz.0.16/4973: 4 locks held by syz.1.17/5004: 4 locks held by syz.2.18/5031: 4 locks held by syz.3.19/5056: 4 locks held by kworker/u4:8/5065: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff80001fcd7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000f50f60e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000ee543948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 4 locks held by syz.4.20/5089: 2 locks held by kworker/u4:10/5120: 4 locks held by syz.5.21/5122: 4 locks held by syz.6.22/5160: 4 locks held by kworker/u4:11/5167: #0: ffff0000c21e0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x678/0x1140 kernel/workqueue.c:2283 #1: ffff8000202e7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6b8/0x1140 kernel/workqueue.c:2285 #2: ffff0000f3ed40e0 (&type->s_umount_key#52){.+.+}-{3:3}, at: trylock_super+0x24/0xf4 fs/super.c:418 #3: ffff0000ee4cc288 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x19c/0x498 fs/jfs/inode.c:102 4 locks held by syz.7.23/5192: 4 locks held by syz.8.24/5228: =============================================