INFO: task syz-executor:7999 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:21704 pid:7999 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6a9/0xcc0 kernel/locking/mutex.c:747 lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 jfs_umount+0x2ef/0x3c0 fs/jfs/jfs_umount.c:114 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x134/0x2b0 fs/super.c:693 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x43b/0x4d0 fs/namespace.c:1259 task_work_run+0x1d4/0x260 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f18e3f9d9d7 RSP: 002b:00007ffe3067d9f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f18e4031f90 RCX: 00007f18e3f9d9d7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3067dab0 RBP: 00007ffe3067dab0 R08: 00007ffe3067eab0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3067eb40 R13: 00007f18e4031f90 R14: 0000000000043e6e R15: 00007ffe3067eb80 Showing all locks held in the system: 2 locks held by kworker/u4:0/11: 1 lock held by khungtaskd/29: #0: ffffffff8d132060 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8d132060 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8d132060 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by getty/5528: #0: ffff88814c7010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217 2 locks held by kworker/0:3/5762: #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #0: ffff888017c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 #1: ffffc9000437fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline] #1: ffffc9000437fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x96f/0x15d0 kernel/workqueue.c:2730 2 locks held by syz-executor/7698: #0: ffff8880221f00e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880221f00e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880221f00e0 (&type->s_umount_key#76){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d549d88 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/7922: #0: ffff88805d8f20e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805d8f20e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805d8f20e0 (&type->s_umount_key#76){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d549d88 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/7999: #0: ffff88803032c0e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88803032c0e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88803032c0e0 (&type->s_umount_key#76){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d549d88 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8655: #0: ffff8880791400e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880791400e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880791400e0 (&type->s_umount_key#76){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d549d88 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz.9.1167/9582: #0: ffff88804e9d60e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88804e9d60e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88804e9d60e0 (&type->s_umount_key#76){++++}-{3:3}, at: mount_bdev+0x1e0/0x2d0 fs/super.c:1641 #1: ffffffff8d549d88 (jfs_log_mutex){+.+.}-{3:3}, at: open_dummy_log fs/jfs/jfs_logmgr.c:1191 [inline] #1: ffffffff8d549d88 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogOpen+0x1af/0xfb0 fs/jfs/jfs_logmgr.c:1066 2 locks held by syz-executor/9645: #0: ffff88807e4b20e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807e4b20e0 (&type->s_umount_key#76){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807e4b20e0 (&type->s_umount_key#76){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 #1: ffffffff8d549d88 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444 1 lock held by syz-executor/11007: #0: ffffffff8d137a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #0: ffffffff8d137a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 2 locks held by syz-executor/11378: #0: ffffffff8e3c0d48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8e3c0d48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x811/0xfa0 net/core/rtnetlink.c:6469 #1: ffffffff8d137a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #1: ffffffff8d137a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004 1 lock held by syz-executor/11383: #0: ffffffff8e3c0d48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8e3c0d48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x811/0xfa0 net/core/rtnetlink.c:6469 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 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+0x18c/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf3d/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 11383 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_const_cmp8+0x0/0x80 kernel/kcov.c:321 Code: c0 4c 89 01 48 c7 44 11 08 05 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 0f 1e fa 48 8b 04 24 65 48 8b 0d 10 95 7c 7e 65 8b 15 11 95 7c RSP: 0018:ffffc9000388f618 EFLAGS: 00000206 RAX: 0380000000000000 RBX: 0080000000000000 RCX: 1ffffd40003622d0 RDX: 0000000000000000 RSI: 0080000000000000 RDI: 0200000000000000 RBP: ffffc9000388f760 R08: ffffea0001b11677 R09: 1ffffd40003622ce R10: dffffc0000000000 R11: fffff940003622cf R12: 00000000000004e0 R13: 0000000000000000 R14: ffffea0001b11680 R15: 0200000000000000 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f97d3add5b8 CR3: 000000004b4be000 CR4: 00000000003506e0 Call Trace: is_zone_device_page include/linux/mmzone.h:1102 [inline] folio_is_zone_device include/linux/mmzone.h:1139 [inline] release_pages+0x2b9/0x2200 mm/swap.c:980 tlb_batch_pages_flush mm/mmu_gather.c:99 [inline] tlb_flush_mmu_free mm/mmu_gather.c:294 [inline] tlb_flush_mmu+0x379/0x510 mm/mmu_gather.c:301 tlb_finish_mmu+0xf9/0x220 mm/mmu_gather.c:425 exit_mmap+0x428/0xb90 mm/mmap.c:3315 __mmput+0x118/0x3c0 kernel/fork.c:1355 exit_mm+0x1f2/0x2c0 kernel/exit.c:569 do_exit+0x8dd/0x2460 kernel/exit.c:870 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x13f0 kernel/signal.c:2902 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa016b5cfce Code: Unable to access opcode bytes at 0x7fa016b5cfa4. RSP: 002b:00007ffc3753fda8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: 0000000000000020 RBX: 000055557dd39500 RCX: 00007fa016b5cfce RDX: 0000000000000020 RSI: 00007fa017944670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc3753fe24 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fa017944670 R15: 0000000000000000