INFO: task syz-executor:5928 blocked for more than 143 se[ 324.845374][ T38] INFO: task syz-executor:5928 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:22048 pid:5928 tgid:5928 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x14de/0x5210 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2dc/0x710 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:552 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+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f739079d1d7 RSP: 002b:00007ffd9fe7b258 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f7390831c3b RCX: 00007f739079d1d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd9fe7b310 RBP: 00007ffd9fe7b310 R08: 00007ffd9fe7c310 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd9fe7c3a0 R13: 00007f7390831c3b R14: 000000000001ae9a R15: 00007ffd9fe7c3e0 INFO: task syz-executor:6069 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:21664 pid:6069 tgid:6069 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x14de/0x5210 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285 rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1647 __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline] rt_mutex_slowlock+0x2dc/0x710 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline] mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:552 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+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2f18c9d1d7 RSP: 002b:00007fff6ab2a718 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f2f18d31c3b RCX: 00007f2f18c9d1d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff6ab2a7d0 RBP: 00007fff6ab2a7d0 R08: 00007fff6ab2b7d0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff6ab2b860 R13: 00007f2f18d31c3b R14: 000000000001eadb R15: 00007fff6ab2b8a0 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:7/1130: 2 locks held by getty/5564: #0: ffff8880329fa0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5923: #0: ffff88802a8b40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802a8b40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88802a8b40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/5928: #0: ffff88804d0360d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88804d0360d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88804d0360d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/6069: #0: ffff88805f9c40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805f9c40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88805f9c40d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/6096: #0: ffff88801e2b80d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88801e2b80d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88801e2b80d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/6098: #0: ffff888038a720d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888038a720d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888038a720d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/6106: #0: ffff888039f720d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888039f720d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888039f720d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/6119: #0: ffff88802068c0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802068c0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88802068c0d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/6202: #0: ffff88802c9620d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88802c9620d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff88802c9620d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 2 locks held by syz-executor/6238: #0: ffff8880383660d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880383660d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880383660d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 #1: ffffffff8e0467f8 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 1 lock held by syz-executor/6251: #0: ffff888020e980d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888020e980d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff888020e980d0 (&type->s_umount_key#56){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 5 locks held by kworker/u8:13/6554: #0: ffff88801b289138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88801b289138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358 #1: ffffc90004bafc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc90004bafc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358 #2: ffffffff8ef3f800 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670 #3: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: wiphy_unregister+0x26a/0xad0 net/wireless/core.c:1180 #4: ffff8880602508b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: wiphy_lock include/net/cfg80211.h:6345 [inline] #4: ffff8880602508b8 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: wiphy_unregister+0x274/0xad0 net/wireless/core.c:1181 3 locks held by syz.5.618/6975: 2 locks held by syz.1.621/6978: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400 Code: e8 4e 38 9d fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 9f 51 02 fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07 RSP: 0018:ffffc900001679d0 EFLAGS: 00000202 RAX: 1ffffffff32df200 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff996f9930 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8525dce0 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff996f96a0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888126595000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f90ad32a000 CR3: 000000007216a000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1961 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline] serial8250_console_write+0x120d/0x1b90 drivers/tty/serial/8250/8250_port.c:3342 console_emit_next_record kernel/printk/printk.c:3111 [inline] console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3217 legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3676 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245