INFO: task kworker/u8:3:42 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:0 pid:42 tgid:42 ppid:2 task_flags:0x4208060 flags:0x00000010 Workqueue: writeback wb_workfn (flush-7:0) Call trace: __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T) context_switch kernel/sched/core.c:5357 [inline] __schedule+0x13b0/0x2864 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xb4/0x230 kernel/sched/core.c:7058 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7115 rwsem_down_write_slowpath+0x6b4/0x10f4 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0xb4/0xc0 kernel/locking/rwsem.c:1591 f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 f2fs_write_inode+0x3a8/0x684 fs/f2fs/inode.c:820 write_inode fs/fs-writeback.c:1525 [inline] __writeback_single_inode+0x5ac/0x13e8 fs/fs-writeback.c:1745 writeback_sb_inodes+0x55c/0xe40 fs/fs-writeback.c:1976 __writeback_inodes_wb+0xec/0x228 fs/fs-writeback.c:2047 wb_writeback+0x3e0/0xd70 fs/fs-writeback.c:2158 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline] wb_do_writeback fs/fs-writeback.c:2315 [inline] wb_workfn+0xa08/0xdc0 fs/fs-writeback.c:2343 process_one_work+0x7e8/0x155c kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3400 kthread+0x5fc/0x75c kernel/kthread.c:463 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:844 Showing all locks held in the system: 4 locks held by kworker/u8:0/12: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff800097d47be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff0000d623c0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff0000d6581410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff0000d6581410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 4 locks held by kworker/u8:1/14: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff800097d67be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff0000c27840e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff0000dac0d410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff0000dac0d410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 1 lock held by khungtaskd/32: #0: ffff80008fa49aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330 4 locks held by kworker/u8:3/42: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff8000993b7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff0000c89ca0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff0000d8581410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff0000d8581410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 4 locks held by kworker/u8:4/241: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff80009b077be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff0000f32e80e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff0000f37f1410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff0000f37f1410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 4 locks held by kworker/u8:5/772: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff80009d2b7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff0000d04600e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff0000d72f5410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff0000d72f5410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 3 locks held by kworker/u8:6/4498: 4 locks held by kworker/u8:8/4702: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff80009da57be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff0000cc7800e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff0000c2f49410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff0000c2f49410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 2 locks held by getty/6328: #0: ffff0000d2a640a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff800099f5e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222 6 locks held by syz.0.17/6753: 8 locks held by syz.1.18/6779: 5 locks held by syz.2.19/6813: 6 locks held by syz.3.20/6839: 6 locks held by syz.4.21/6876: 5 locks held by syz.5.22/6915: 4 locks held by kworker/u8:9/6931: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff8000a3727be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff0000f9c2e0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff000100ba9410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff000100ba9410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 4 locks held by syz.6.23/6955: 4 locks held by kworker/u8:11/6992: #0: ffff0000c1f82948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3210 #1: ffff80009ed37be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3210 #2: ffff00010405e0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563 #3: ffff000109bfd410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline] #3: ffff000109bfd410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x4b8/0x6ec fs/f2fs/segment.c:464 5 locks held by syz.7.24/6993: 5 locks held by syz.8.25/7030: 2 locks held by kworker/u8:13/7056: 4 locks held by syz.9.26/7074: =============================================