INFO: task syz-executor:4678 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:21840 pid: 4678 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116 jfs_put_super+0x88/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4c7df2d317 RSP: 002b:00007ffe46909e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f4c7dfbde5b RCX: 00007f4c7df2d317 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe46909f10 RBP: 00007ffe46909f10 R08: 00007ffe4690af10 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe4690afa0 R13: 00007f4c7dfbde5b R14: 000000000001abd0 R15: 00007ffe4690afe0 INFO: task syz-executor:4687 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21808 pid: 4687 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116 jfs_put_super+0x88/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f0058749317 RSP: 002b:00007ffd34db8dd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f00587d9e5b RCX: 00007f0058749317 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd34db8e90 RBP: 00007ffd34db8e90 R08: 00007ffd34db9e90 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd34db9f20 R13: 00007f00587d9e5b R14: 000000000001ac63 R15: 00007ffd34db9f60 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3947: #0: ffff88814cadb098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 2 locks held by syz-executor/4678: #0: ffff8880246de0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/4679: #0: ffff888023e280e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/4687: #0: ffff8880763d40e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/5104: #0: ffff88801fede0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/5126: #0: ffff888079b820e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/5145: #0: ffff88801f1d00e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/5148: #0: ffff88807b90a0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/5150: #0: ffff8880787880e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 2 locks held by syz-executor/5212: #0: ffff88804f1fe0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffffffff8c6c61e8 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb0/0x520 fs/jfs/jfs_logmgr.c:1452 1 lock held by syz-executor/5226: #0: ffff88807a3c80e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365 1 lock held by syz-executor/5278: #0: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 2 locks held by syz.6.707/6678: 2 locks held by syz.0.708/6680: 1 lock held by syz.5.709/6682: 2 locks held by syz.2.711/6685: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5978 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:216 Code: 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48 8d 7e 01 8b 89 14 16 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89 3a 0f 1f 80 00 00 00 00 48 8b 04 24 65 48 8b 0d 44 4e 89 7e 65 8b RSP: 0018:ffffc9000858fb78 EFLAGS: 00000293 RAX: ffffffff8168ab1c RBX: ffffc9000858fd01 RCX: ffff88801e935940 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000858fd00 R08: ffff88801e93595b R09: 1ffff11003d26b2b R10: dffffc0000000000 R11: ffffed1003d26b2c R12: ffffc9000858fd80 R13: 000000000000c350 R14: 0000000000989680 R15: dffffc0000000000 FS: 0000555573d0f500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f37b5f3f000 CR3: 00000000473a4000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hrtimer_start_range_ns+0x9c/0xc20 kernel/time/hrtimer.c:1280 hrtimer_start_expires include/linux/hrtimer.h:434 [inline] hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1947 [inline] do_nanosleep+0x1a1/0x770 kernel/time/hrtimer.c:2023 hrtimer_nanosleep+0x33e/0x590 kernel/time/hrtimer.c:2079 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1314 [inline] __se_sys_clock_nanosleep+0x30b/0x3a0 kernel/time/posix-timers.c:1291 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ff7a7cf198e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffc08062cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000555573d0f500 RCX: 00007ff7a7cf198e RDX: 00007ffc08062d50 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffc08062dbc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388 R13: 00000000000927c0 R14: 000000000004e4a8 R15: 00007ffc08062e10