INFO: task syz-executor:3511 blocked for more than 143 seconds. Not tainted 5.15.161-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20760 pid: 3511 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_timeout+0xac/0x300 kernel/time/timer.c:1890 do_wait_for_common+0x2d9/0x480 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 kthread_stop+0x178/0x580 kernel/kthread.c:664 ext4_stop_mmpd+0x43/0xb0 fs/ext4/mmp.c:263 ext4_put_super+0xac5/0x1060 fs/ext4/super.c:1266 generic_shutdown_super+0x136/0x2c0 fs/super.c:475 kill_block_super+0x7a/0xe0 fs/super.c:1414 deactivate_locked_super+0xa0/0x110 fs/super.c:335 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143 task_work_run+0x129/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f9d8b2e1f07 RSP: 002b:00007fffe5a12a48 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f9d8b34e515 RCX: 00007f9d8b2e1f07 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffe5a12b00 RBP: 00007fffe5a12b00 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffe5a13bd0 R13: 00007f9d8b34e515 R14: 000000000001bcf3 R15: 0000000000000009 INFO: task kmmpd-loop2:4703 blocked for more than 143 seconds. Not tainted 5.15.161-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kmmpd-loop2 state:D stack:27608 pid: 4703 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 percpu_rwsem_wait+0x3e1/0x470 kernel/locking/percpu-rwsem.c:160 __percpu_down_read+0xd0/0x100 kernel/locking/percpu-rwsem.c:174 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] __sb_start_write include/linux/fs.h:1811 [inline] sb_start_write include/linux/fs.h:1881 [inline] write_mmp_block+0x2f0/0x390 fs/ext4/mmp.c:66 kmmpd+0x292/0xa90 fs/ext4/mmp.c:248 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3258: #0: ffff88802422e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc9000209b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 1 lock held by syz-executor/3511: #0: ffff88805e3140e0 (&type->s_umount_key#32){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365 3 locks held by kworker/u4:11/4501: 1 lock held by kmmpd-loop2/4703: #0: ffff88805e314460 (sb_writers#5){++++}-{0:0}, at: kmmpd+0x292/0xa90 fs/ext4/mmp.c:248 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.161-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7382 Comm: syz.2.1014 Not tainted 5.15.161-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0033:0x7ff3f71494fb Code: cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 47 0f b6 0c 08 <45> 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01 49 89 47 10 83 RSP: 002b:00007ff3f5d034b0 EFLAGS: 00000206 RAX: 0000000002fb04e8 RBX: 00007ff3f5d03550 RCX: 000000000000008d RDX: 0000000000000001 RSI: 0000000000000001 RDI: 00007ff3f5d035f0 RBP: 0000000000000102 R08: 00007ff3ed87f000 R09: 0000000000000000 R10: 0000000000000000 R11: 00007ff3f5d03560 R12: 0000000000000001 R13: 00007ff3f7303fa0 R14: 0000000000000000 R15: 00007ff3f5d035f0 FS: 00007ff3f5d046c0 GS: 0000000000000000