INFO: task syz-executor:15823 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21072 pid:15823 tgid:15823 ppid:1 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 jfs_umount+0x2ef/0x3c0 fs/jfs/jfs_umount.c:114 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x135/0x2c0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1729 deactivate_locked_super+0xbc/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd0d2590a77 RSP: 002b:00007fffa7f38f58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fd0d2613d7d RCX: 00007fd0d2590a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffa7f39010 RBP: 00007fffa7f39010 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fffa7f3a0a0 R13: 00007fd0d2613d7d R14: 00000000001271af R15: 00007fffa7f3a0e0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5583: #0: ffff88802fd890a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/15395: #0: ffff8880402160e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880402160e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880402160e0 (&type->s_umount_key#91){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffffffff8e37c368 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/15823: #0: ffff88803a46e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88803a46e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88803a46e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffffffff8e37c368 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/15932: #0: ffff8880688840e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880688840e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880688840e0 (&type->s_umount_key#91){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffffffff8e37c368 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz.1.2814/16836: #0: ffff8880402160e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880402160e0 (&type->s_umount_key#91){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 2 locks held by syz-executor/17652: #0: ffff888060e3a0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff888060e3a0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff888060e3a0e0 (&type->s_umount_key#91){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffffffff8e37c368 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5810 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:update_rq_clock_pelt kernel/sched/pelt.h:102 [inline] RIP: 0010:update_rq_clock_task kernel/sched/core.c:828 [inline] RIP: 0010:update_rq_clock+0x2a9/0x5b0 kernel/sched/core.c:853 Code: e8 dc 21 07 00 eb 1f 4c 8d bb 40 0b 00 00 4c 89 f8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ff e8 be c1 95 00 4d 01 2f f3 0f 1e fa <4c> 8d bb 00 0b 00 00 4c 89 f8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 RSP: 0018:ffffc90003eaf6b8 EFLAGS: 00000046 RAX: 1ffff11017127570 RBX: ffff8880b893a040 RCX: ffffffff9274fe03 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002 RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520007d5ec8 R12: 1ffff11017127585 R13: 00000000000010ea R14: ffff8880b893ac28 R15: 0000000000000000 FS: 000055557e064500(0000) GS:ffff888126239000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3dcedb42f8 CR3: 000000006f94d000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: sched_balance_update_blocked_averages+0x20a/0x1580 kernel/sched/fair.c:9901 sched_balance_newidle+0x46d/0x1030 kernel/sched/fair.c:12842 balance_fair+0x3b/0x80 kernel/sched/fair.c:8721 prev_balance kernel/sched/core.c:5941 [inline] pick_next_task kernel/sched/core.c:6091 [inline] __schedule+0x2b38/0x4cc0 kernel/sched/core.c:6870 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 do_nanosleep+0x1c5/0x610 kernel/time/hrtimer.c:2116 hrtimer_nanosleep+0x169/0x360 kernel/time/hrtimer.c:2163 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1398 [inline] __se_sys_clock_nanosleep+0x339/0x390 kernel/time/posix-timers.c:1375 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f92907c1fc3 Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 9e 95 1f 00 00 74 14 b8 e6 00 00 00 0f 05 d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10 RSP: 002b:00007fff9e207dc8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f92907c1fc3 RDX: 00007fff9e207de0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 7fffffffffffffff R09: 3fffffffffffffff R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff9e208230 R13: 0000000000000004 R14: 00007fff9e207e1c R15: 00007fff9e207eb0