INFO: task syz-executor:6972 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:21896 pid:6972 tgid:6972 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x1681/0x54c0 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7563
rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1659
__rt_mutex_slowlock kernel/locking/rtmutex.c:1736 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1776 [inline]
rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1816
__rt_mutex_lock kernel/locking/rtmutex.c:1831 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:553
lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441
jfs_umount+0x2fb/0x3d0 fs/jfs/jfs_umount.c:124
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:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f86092dda57
RSP: 002b:00007ffdf2646568 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f8609372048 RCX: 00007f86092dda57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdf2646620
RBP: 00007ffdf2646620 R08: 00007ffdf2647620 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdf26476b0
R13: 00007f8609372048 R14: 00000000000400f3 R15: 00007ffdf26476f0
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8dfc7ec0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc7ec0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfc7ec0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:4/66:
#0: ffff8880324c9938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline]
#0: ffff8880324c9938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385
#1: ffffc9000151fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline]
#1: ffffc9000151fc40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385
#2: ffffffff8f361078 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f361078 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4206
8 locks held by kworker/u8:7/781:
1 lock held by udevd/5163:
2 locks held by getty/5554:
#0: ffff8880379540a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5800:
#0: ffff8880671c80d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880671c80d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880671c80d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441
2 locks held by syz-executor/6618:
#0: ffff88802a54c0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802a54c0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88802a54c0d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441
2 locks held by syz-executor/6853:
#0: ffff8880666ea0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880666ea0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880666ea0d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441
2 locks held by syz-executor/6972:
#0: ffff88803668e0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88803668e0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88803668e0d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441
2 locks held by syz-executor/7480:
#0: ffff8880654440d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880654440d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880654440d0 (&type->s_umount_key#59){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1441
2 locks held by syz.8.311/7951:
#0: ffff88805f8220d0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: open_dummy_log fs/jfs/jfs_logmgr.c:1189 [inline]
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogOpen+0x1a1/0xfa0 fs/jfs/jfs_logmgr.c:1064
2 locks held by syz.4.332/8405:
#0: ffff8880672180d0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: open_dummy_log fs/jfs/jfs_logmgr.c:1189 [inline]
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogOpen+0x1a1/0xfa0 fs/jfs/jfs_logmgr.c:1064
1 lock held by syz.0.357/8655:
#0: ffff8880671c80d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff8880671c80d0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
2 locks held by syz.2.358/8684:
#0: ffff888035f300d0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: open_dummy_log fs/jfs/jfs_logmgr.c:1189 [inline]
#1: ffffffff8e450138 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogOpen+0x1a1/0xfa0 fs/jfs/jfs_logmgr.c:1064
4 locks held by syz.9.371/8851:
3 locks held by syz-executor/8853:
3 locks held by syz.1.370/8856:
3 locks held by syz-executor/8859:
=============================================
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 03/18/2026
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+0xfaa/0x1000 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 8327 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:839 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
RIP: 0010:unwind_next_frame+0xcc/0x2550 arch/x86/kernel/unwind_orc.c:495
Code: 00 00 00 00 48 c7 c7 c0 7e fc 8d 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 fd 51 29 00 48 83 c4 08 e8 14 35 b0 09 <85> c0 74 3a e8 2b 8e 32 00 84 c0 75 31 e8 02 35 b0 09 85 c0 74 28
RSP: 0018:ffffc9000601f6d8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff822a105e RCX: ffff88802d3b0000
RDX: 000000001bb514ad RSI: ffffffff8d88386a RDI: ffffffff8ba6b800
RBP: dffffc0000000000 R08: ffffffff81765576 R09: ffffffff8dfc7ec0
R10: ffffc9000601f7f8 R11: ffffffff81aef0c0 R12: ffffc9000601f7e0
R13: 1ffff92000c03ef5 R14: ffffc9000601f7a8 R15: ffffffff81765576
FS: 00007fe4346df880(0000) GS:ffff888126121000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff9fa6aff8 CR3: 0000000034c5a000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5295 [inline]
__kvmalloc_node_noprof+0x3c2/0x8e0 mm/slub.c:6828
seq_buf_alloc fs/seq_file.c:39 [inline]
seq_read_iter+0x203/0xe20 fs/seq_file.c:211
new_sync_read fs/read_write.c:493 [inline]
vfs_read+0x58b/0xa80 fs/read_write.c:574
ksys_read+0x156/0x270 fs/read_write.c:717
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe4347cd407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffe8443a6d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fe4346df880 RCX: 00007fe4347cd407
RDX: 0000000000001000 RSI: 000055d9c2875a70 RDI: 0000000000000008
RBP: 00007fe434915ff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a
R13: 00007fe434915ea0 R14: 0000000000000000 R15: 000055d9c2802280