INFO: task kworker/u4:7:4046 blocked for more than 143 seconds. Not tainted 6.1.0-rc5-syzkaller-00015-g81e7cfa3a9eb #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:7 state:D stack:18176 pid:4046 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: context_switch kernel/sched/core.c:5191 [inline] __schedule+0x8c9/0xd70 kernel/sched/core.c:6503 schedule+0xcb/0x190 kernel/sched/core.c:6579 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6638 __mutex_lock_common+0xe4f/0x26e0 kernel/locking/mutex.c:679 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799 jfs_commit_inode+0x20d/0x5a0 fs/jfs/inode.c:102 jfs_write_inode+0x13d/0x210 fs/jfs/inode.c:132 write_inode fs/fs-writeback.c:1440 [inline] __writeback_single_inode+0x4d6/0x670 fs/fs-writeback.c:1652 writeback_sb_inodes+0xb3b/0x18f0 fs/fs-writeback.c:1870 __writeback_inodes_wb+0x125/0x420 fs/fs-writeback.c:1941 wb_writeback+0x440/0x7b0 fs/fs-writeback.c:2046 wb_check_background_flush fs/fs-writeback.c:2112 [inline] wb_do_writeback fs/fs-writeback.c:2200 [inline] wb_workfn+0xb3f/0xef0 fs/fs-writeback.c:2227 process_one_work+0x877/0xdb0 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 INFO: task syz-executor.2:12102 blocked for more than 144 seconds. Not tainted 6.1.0-rc5-syzkaller-00015-g81e7cfa3a9eb #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:19576 pid:12102 ppid:3678 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5191 [inline] __schedule+0x8c9/0xd70 kernel/sched/core.c:6503 schedule+0xcb/0x190 kernel/sched/core.c:6579 rwsem_down_write_slowpath+0xfc1/0x1480 kernel/locking/rwsem.c:1190 __down_write_common kernel/locking/rwsem.c:1305 [inline] __down_write kernel/locking/rwsem.c:1314 [inline] down_write+0x231/0x270 kernel/locking/rwsem.c:1563 inode_lock include/linux/fs.h:756 [inline] open_last_lookups fs/namei.c:3478 [inline] path_openat+0x7b9/0x2df0 fs/namei.c:3710 do_filp_open+0x264/0x4f0 fs/namei.c:3740 do_sys_openat2+0x124/0x4e0 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1337 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f2b6968b639 RSP: 002b:00007f2b6a360168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f2b697abf80 RCX: 00007f2b6968b639 RDX: 000000000000275a RSI: 0000000020000300 RDI: ffffffffffffff9c RBP: 00007f2b696e6ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffff313297f R14: 00007f2b6a360300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d327330 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d327b30 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8d327160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:4/56: #0: ffff888018613938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc90001577d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff88809d49c0e0 (&type->s_umount_key#87){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88803cd16788 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x20d/0x5a0 fs/jfs/inode.c:102 2 locks held by getty/3307: #0: ffff888144faa098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x53b/0x1650 drivers/tty/n_tty.c:2177 4 locks held by kworker/u4:7/4046: #0: ffff888018613938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7f2/0xdb0 #1: ffffc900068afd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x831/0xdb0 kernel/workqueue.c:2264 #2: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88803cf1c288 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x20d/0x5a0 fs/jfs/inode.c:102 2 locks held by syz-executor.2/12102: #0: ffff888079cbc460 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393 #1: ffff88803cf1c640 (&type->i_mutex_dir_key#16){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] #1: ffff88803cf1c640 (&type->i_mutex_dir_key#16){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3478 [inline] #1: ffff88803cf1c640 (&type->i_mutex_dir_key#16){+.+.}-{3:3}, at: path_openat+0x7b9/0x2df0 fs/namei.c:3710 4 locks held by syz-executor.2/12103: 2 locks held by syz-executor.2/12226: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 2 locks held by syz-executor.2/12227: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 2 locks held by syz-executor.0/12283: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 2 locks held by syz-executor.0/12284: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 4 locks held by syz-executor.0/12287: 2 locks held by syz-executor.0/12308: #0: ffff88809d49c460 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393 #1: ffff88803cd16b40 (&type->i_mutex_dir_key#16){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] #1: ffff88803cd16b40 (&type->i_mutex_dir_key#16){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3478 [inline] #1: ffff88803cd16b40 (&type->i_mutex_dir_key#16){+.+.}-{3:3}, at: path_openat+0x7b9/0x2df0 fs/namei.c:3710 2 locks held by syz-executor.4/12317: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 2 locks held by syz-executor.4/12320: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 2 locks held by syz-executor.2/12348: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 2 locks held by syz-executor.2/12349: #0: ffff888079cbc0e0 (&type->s_umount_key#87){++++}-{3:3}, at: iterate_supers+0xb0/0x1f0 fs/super.c:722 #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881473d47d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x264/0xaa0 fs/fs-writeback.c:2704 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.0-rc5-syzkaller-00015-g81e7cfa3a9eb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106 nmi_cpu_backtrace+0x46f/0x4f0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ba/0x420 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xcf5/0xd40 kernel/hung_task.c:377 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3872 Comm: syz-fuzzer Not tainted 6.1.0-rc5-syzkaller-00015-g81e7cfa3a9eb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0033:0x558c4a Code: 24 08 eb bc 4c 8d 6c 24 18 4d 39 2c 24 75 ce 49 89 24 24 eb c8 cc cc cc cc cc cc cc cc cc cc cc 49 3b 66 10 76 2d 48 83 ec 10 <48> 89 6c 24 08 48 8d 6c 24 08 4d 8b 66 20 4d 85 e4 75 27 48 89 44 RSP: 002b:000000c02bd30bb0 EFLAGS: 00000202 RAX: 000000000133dee0 RBX: 000000c00063c000 RCX: 0000000000cef9f8 RDX: 0000000000033bc0 RSI: 0000000000558c40 RDI: 000000c00009c078 RBP: 000000c02bd30c60 R08: 000000003c84c8af R09: 0000000000ce2a78 R10: 0000000000ce2978 R11: 000000c01d0f4ee0 R12: 000000c02bd30c48 R13: 0000000000000000 R14: 000000c0000bc000 R15: 00007fa57d26b310 FS: 000000c01fb37490 GS: 0000000000000000