INFO: task syz-executor:6629 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:21800 pid:6629  tgid:6629  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:240
 __wait_on_bit+0xb6/0x310 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:67
 wait_on_bit include/linux/wait_bit.h:77 [inline]
 gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1335
 gfs2_glock_nq_init fs/gfs2/glock.h:252 [inline]
 __gfs2_lookup+0x117/0x270 fs/gfs2/inode.c:984
 __lookup_slow+0x297/0x3d0 fs/namei.c:1808
 lookup_slow+0x53/0x70 fs/namei.c:1825
 walk_component+0x2d2/0x400 fs/namei.c:2129
 lookup_last fs/namei.c:2630 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2654
 filename_lookup+0x212/0x570 fs/namei.c:2683
 user_path_at+0x3a/0x60 fs/namei.c:3127
 ksys_umount fs/namespace.c:2112 [inline]
 __do_sys_umount fs/namespace.c:2120 [inline]
 __se_sys_umount fs/namespace.c:2118 [inline]
 __x64_sys_umount+0xee/0x160 fs/namespace.c:2118
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f007f38ff17
RSP: 002b:00007ffe7f204ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f007f411c05 RCX: 00007f007f38ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe7f204da0
RBP: 00007ffe7f204da0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe7f205e90
R13: 00007f007f411c05 R14: 0000000000032e6a R15: 00007ffe7f208050
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:lock_acquire+0xb/0x360 kernel/locking/lockdep.c:5828
Code: 95 c0 e9 88 d0 e2 09 cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 <41> 54 53 48 83 ec 60 4d 89 ce 45 89 c7 41 89 cc 89 54 24 04 89 f3
RSP: 0018:ffffc900001d7228 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff8a768c01 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e339f20
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc900001d7378 R11: ffffffff81ac3a20 R12: 1ffff9200003ae65
R13: ffffc900001d7360 R14: ffffc900001d7328 R15: ffffffff8172c195
FS:  0000000000000000(0000) GS:ffff888125b08000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055a060c02498 CR3: 00000000456b2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:330 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4281
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:659
 alloc_skb include/linux/skbuff.h:1336 [inline]
 j1939_tp_tx_dat_new+0x31/0x480 net/can/j1939/transport.c:596
 j1939_tp_tx_dat net/can/j1939/transport.c:638 [inline]
 j1939_session_tx_dat net/can/j1939/transport.c:839 [inline]
 j1939_xtp_txnext_transmiter net/can/j1939/transport.c:901 [inline]
 j1939_tp_txtimer+0x134d/0x2650 net/can/j1939/transport.c:1161
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1842
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968
 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:160
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>