INFO: task syz-executor:6877 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21256 pid:6877 tgid:6877 ppid:1 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b88/0x5240 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746 lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 jfs_umount+0x2ce/0x3a0 fs/jfs/jfs_umount.c:114 jfs_put_super+0x8a/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x13b/0x2d0 fs/super.c:642 kill_block_super+0x44/0x90 fs/super.c:1710 deactivate_locked_super+0xc6/0x130 fs/super.c:473 cleanup_mnt+0x422/0x4c0 fs/namespace.c:1435 task_work_run+0x253/0x310 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fae06f8f497 RSP: 002b:00007ffee2bf62d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007fae07010854 RCX: 00007fae06f8f497 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffee2bf6390 RBP: 00007ffee2bf6390 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffee2bf7420 R13: 00007fae07010854 R14: 000000000003d9d2 R15: 00007ffee2bf7460 Showing all locks held in the system: 3 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5586: #0: ffff888033dc80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036532f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/6223: #0: ffff88804b70e0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88804b70e0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88804b70e0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/6877: #0: ffff8880851300e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880851300e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880851300e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/7345: #0: ffff88803d08a0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88803d08a0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88803d08a0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/7450: #0: ffff888034eae0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888034eae0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888034eae0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/7509: #0: ffff888049ae60e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888049ae60e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888049ae60e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/7514: #0: ffff888056dee0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888056dee0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888056dee0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/8600: #0: ffff8880320200e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880320200e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880320200e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 2 locks held by syz-executor/9263: #0: ffff88805266c0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805266c0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805266c0e0 (&type->s_umount_key#55){+.+.}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 #1: ffffffff8f169768 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb2/0x530 fs/jfs/jfs_logmgr.c:1444 1 lock held by syz-executor/9389: #0: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998 1 lock held by syz.2.655/10298: 2 locks held by syz.1.656/10300: #0: ffffffff900fd788 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff900fd788 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x767/0xd70 net/core/rtnetlink.c:6961 #1: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #1: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x384/0x830 kernel/rcu/tree_exp.h:998 1 lock held by syz.1.656/10302: #0: ffffffff900fd788 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff900fd788 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x767/0xd70 net/core/rtnetlink.c:6961 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b9/0x940 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153 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: 2999 Comm: kworker/u8:8 Not tainted 6.15.0-rc2-syzkaller-00278-gfc96b232f8e7 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:switch_mm_irqs_off+0xa0/0xa40 arch/x86/mm/tlb.c:780 Code: 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 4a 89 04 39 48 89 4c 24 38 42 c7 44 39 08 01 f2 02 f3 65 48 8b 05 b5 a7 fa 11 48 89 44 24 08 <65> 66 44 8b 25 b7 a7 fa 11 65 8a 05 20 a8 fa 11 88 44 24 07 e8 97 RSP: 0018:ffffc9000b54f600 EFLAGS: 00000012 RAX: ffff88807e62e400 RBX: ffffc9000b54f680 RCX: 1ffff920016a9ec8 RDX: ffff88805a668000 RSI: ffff8880433bb200 RDI: ffff88807e62e400 RBP: ffffc9000b54f6f0 R08: ffff8880433bb2c3 R09: 1ffff11008677658 R10: dffffc0000000000 R11: ffffed1008677659 R12: 0000000000000000 R13: ffffc9000b54f690 R14: ffff8880302adf60 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff88812509a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffeac8ecfb8 CR3: 0000000024c46000 CR4: 0000000000350ef0 Call Trace: context_switch kernel/sched/core.c:5366 [inline] __schedule+0x13a1/0x5240 kernel/sched/core.c:6767 preempt_schedule_irq+0xfe/0x1c0 kernel/sched/core.c:7090 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:869 [inline] RIP: 0010:batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] RIP: 0010:batadv_nc_worker+0x1ee/0x610 net/batman-adv/network-coding.c:719 Code: e8 07 4c 33 f6 48 8b 6d 00 48 85 ed 74 17 48 81 c5 38 fe ff ff 74 0e e8 00 0d c9 f5 eb b8 e8 f9 0c c9 f5 eb 05 e8 f2 0c c9 f5 fd fa 35 00 89 c3 31 ff 89 c6 e8 22 11 c9 f5 85 db 74 15 e8 a9 RSP: 0018:ffffc9000b54fab8 EFLAGS: 00000293 RAX: ffffffff8bf9adc7 RBX: ffff888027735700 RCX: ffff8880302ada00 RDX: 0000000000000000 RSI: ffffffff8ca1b700 RDI: ffffffff8ca1b6c0 RBP: 0000000000000000 R08: ffffffff8bf9ace1 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888035ab0d80 R13: 000000000000012f R14: ffff888027735700 R15: dffffc0000000000 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac5/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b9/0x940 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245