INFO: task syz.0.904:9308 blocked for more than 143 seconds.
Tainted: G U 6.14.0-rc4-syzkaller-00248-g03d38806a902 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.904 state:D stack:27936 pid:9308 tgid:9307 ppid:5832 task_flags:0x400140 flags:0x00000006
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0xf43/0x5890 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
__mutex_lock_common kernel/locking/mutex.c:662 [inline]
__mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730
nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596
nfsd_umount+0x48/0xe0 fs/nfsd/nfsctl.c:1386
deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
deactivate_super+0xde/0x100 fs/super.c:506
cleanup_mnt+0x222/0x450 fs/namespace.c:1413
task_work_run+0x14e/0x250 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+0x27b/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa3b6b8d169
RSP: 002b:00007fa3b49f6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffea RBX: 00007fa3b6da5fa0 RCX: 00007fa3b6b8d169
RDX: 0000400000000080 RSI: 0000400000000040 RDI: 0000000000000000
RBP: 00007fa3b6c0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa3b6da5fa0 R15: 00007ffc4614fdb8
Showing all locks held in the system:
3 locks held by kworker/u8:1/12:
1 lock held by khungtaskd/30:
#0: ffffffff8e1bccc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e1bccc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e1bccc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746
4 locks held by kworker/u8:10/3600:
#0: ffff88801bef5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213
#1: ffffc9000c4d7d18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214
#2: ffffffff8fee3650 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xca/0xb30 net/core/net_namespace.c:606
#3: ffffffff8fef9368 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x64/0x3c0 net/caif/caif_dev.c:528
2 locks held by syz.1.745/8686:
#0: ffffffff8ff9a0f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e5bfe68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xe3/0x1b40 fs/nfsd/nfsctl.c:1922
2 locks held by syz.0.904/9308:
#0: ffff88806161e0e0 (&type->s_umount_key#50){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88806161e0e0 (&type->s_umount_key#50){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88806161e0e0 (&type->s_umount_key#50){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:505
#1: ffffffff8e5bfe68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596
2 locks held by syz.4.1023/9811:
#0: ffffffff8ff9a0f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e5bfe68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1629
2 locks held by syz.2.1031/9848:
#0: ffffffff8ff9a0f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e5bfe68 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1629
1 lock held by syz.5.1487/11590:
#0: ffffffff8e1c8000 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x700 kernel/rcu/tree.c:3741
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G U 6.14.0-rc4-syzkaller-00248-g03d38806a902 #0
Tainted: [U]=USER
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+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0xf62/0x12b0 kernel/hung_task.c:399
kthread+0x3af/0x750 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:1 Tainted: G U 6.14.0-rc4-syzkaller-00248-g03d38806a902 #0
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:debug_lockdep_rcu_enabled+0x2e/0x40 kernel/rcu/update.c:322
Code: 8b 05 e2 54 0d 05 85 c0 74 20 8b 05 00 87 0d 05 85 c0 74 16 65 48 8b 05 60 b3 ae 74 8b 80 ec 0a 00 00 85 c0 0f 94 c0 0f b6 c0 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 90 90 90 90
RSP: 0000:ffffc90000117b20 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff888061054660 RCX: ffffffff8b23bcee
RDX: ffff88801d285a00 RSI: ffffffff8b23b939 RDI: 0000000000000001
RBP: 00000000000000cc R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000002 R12: 0000000000000001
R13: 0000000000000001 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b308faff8 CR3: 00000000797e0000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:878 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0x85e/0x1060 net/batman-adv/network-coding.c:719
process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400
kthread+0x3af/0x750 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244