INFO: task syz.2.467:9036 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.467 state:D stack:25864 pid:9036 ppid:8654 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
open_dummy_log fs/jfs/jfs_logmgr.c:1191 [inline]
lmLogOpen+0x1af/0xfb0 fs/jfs/jfs_logmgr.c:1066
jfs_mount_rw+0xea/0x670 fs/jfs/jfs_mount.c:257
jfs_fill_super+0x592/0xac0 fs/jfs/super.c:565
mount_bdev+0x22b/0x2d0 fs/super.c:1643
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3377
do_mount fs/namespace.c:3717 [inline]
__do_sys_mount fs/namespace.c:3926 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3903
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8c6e39038a
RSP: 002b:00007f8c6f2b6e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f8c6f2b6ef0 RCX: 00007f8c6e39038a
RDX: 00002000000001c0 RSI: 0000200000000180 RDI: 00007f8c6f2b6eb0
RBP: 00002000000001c0 R08: 00007f8c6f2b6ef0 R09: 0000000000000002
R10: 0000000000000002 R11: 0000000000000246 R12: 0000200000000180
R13: 00007f8c6f2b6eb0 R14: 0000000000006188 R15: 00002000000009c0
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2fc20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by kworker/u4:7/2872:
2 locks held by getty/5548:
#0: ffff88814cad60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
3 locks held by kworker/0:4/5854:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900048efd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900048efd00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffff88805eb87240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x26c/0x3170 drivers/net/netdevsim/fib.c:1491
2 locks held by syz-executor/6846:
#0: ffff88801f7ec0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88801f7ec0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88801f7ec0e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444
2 locks held by syz-executor/8312:
#0: ffff88801eaf40e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88801eaf40e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88801eaf40e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444
2 locks held by syz-executor/8357:
#0: ffff88807dfd80e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88807dfd80e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88807dfd80e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444
2 locks held by syz-executor/8575:
#0: ffff888079e580e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff888079e580e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff888079e580e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444
2 locks held by syz-executor/8790:
#0: ffff888040b880e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff888040b880e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff888040b880e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444
2 locks held by syz.2.467/9036:
#0: ffff88807cb960e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88807cb960e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88807cb960e0 (&type->s_umount_key#58){++++}-{3:3}, at: mount_bdev+0x1e8/0x2d0 fs/super.c:1641
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: open_dummy_log fs/jfs/jfs_logmgr.c:1191 [inline]
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogOpen+0x1af/0xfb0 fs/jfs/jfs_logmgr.c:1066
2 locks held by syz-executor/9233:
#0: ffff888020eae0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff888020eae0e0 (&type->s_umount_key#58){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff888020eae0e0 (&type->s_umount_key#58){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffffffff8d148468 (jfs_log_mutex){+.+.}-{3:3}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1444
2 locks held by syz-executor/11168:
#0: ffffffff8dfbc488 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfbc488 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6472
#1: ffffffff8cd35bf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#1: ffffffff8cd35bf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 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+0xf41/0xf80 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
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5854 Comm: kworker/0:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events kfree_rcu_work
RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:50 [inline]
RIP: 0010:unwind_next_frame+0xa6/0x2970 arch/x86/kernel/unwind_orc.c:475
Code: 00 00 4c 89 e3 48 c1 eb 03 42 0f b6 04 2b 84 c0 0f 85 df 21 00 00 41 8b 2c 24 31 ff 89 ee e8 f1 ef 4a 00 89 ac 24 8c 00 00 00 <85> ed 74 77 4c 89 74 24 60 48 89 5c 24 18 bf 01 00 00 00 e8 72 c6
RSP: 0018:ffffc900048ef4f8 EFLAGS: 00000293
RAX: ffffffff813aa35f RBX: 1ffff9200091deb9 RCX: 0000000000000000
RDX: ffff88805e665a00 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffc900048ef690 R09: 0000000000000005
R10: 0000000000000004 R11: 0000000000000000 R12: ffffc900048ef5c8
R13: dffffc0000000000 R14: ffffc900048ef600 R15: ffffffff8171580b
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555564405c8 CR3: 000000003d9b7000 CR4: 00000000003506f0
Call Trace:
<TASK>
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1806 [inline]
slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832
slab_free mm/slub.c:3816 [inline]
kmem_cache_free_bulk+0x347/0x460 mm/slub.c:3934
kfree_bulk include/linux/slab.h:517 [inline]
kvfree_rcu_bulk+0x1eb/0x470 kernel/rcu/tree.c:3032
kfree_rcu_work+0x32f/0x3a0 kernel/rcu/tree.c:3111
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
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
</TASK>