INFO: task syz.1.9686:9210 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.9686 state:D stack:25792 pid:9210 tgid:9209 ppid:5932 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x14bc/0x5000 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7017
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:776
nfsd_nl_version_set_doit+0xc2/0x770 fs/nfsd/nfsctl.c:1730
genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:733
____sys_sendmsg+0x505/0x820 net/socket.c:2608
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2662
__sys_sendmsg net/socket.c:2694 [inline]
__do_sys_sendmsg net/socket.c:2699 [inline]
__se_sys_sendmsg net/socket.c:2697 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2697
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f291958f749
RSP: 002b:00007f291a370038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f29197e5fa0 RCX: 00007f291958f749
RDX: 0000000004008090 RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007f2919613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f29197e6038 R14: 00007f29197e5fa0 R15: 00007ffe1b77ab48
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8df41cc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5598:
#0: ffff88814de090a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz.3.9034/6773:
#0: ffffffff8f35d170 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e233a08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2cb/0x960 fs/nfsd/nfsctl.c:1590
2 locks held by syz.1.9686/9210:
#0: ffffffff8f35d170 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e233a08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xc2/0x770 fs/nfsd/nfsctl.c:1730
2 locks held by syz-executor/9550:
2 locks held by syz.2.9822/9673:
#0: ffffffff8f35d170 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e233a08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xc2/0x770 fs/nfsd/nfsctl.c:1730
6 locks held by syz.7.10540/12593:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
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+0xf3c/0xf80 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12593 Comm: syz.7.10540 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:222 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:233 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4879 [inline]
RIP: 0010:__lock_acquire+0x51d/0x2cf0 kernel/locking/lockdep.c:5187
Code: ff c7 49 63 8e 28 0b 00 00 48 83 c3 28 41 89 c4 49 39 cf 0f 8d c7 00 00 00 49 83 ff 31 0f 83 83 00 00 00 8b 03 25 ff 1f 00 00 <48> 0f a3 05 9b 71 e0 11 73 10 48 69 c0 c8 00 00 00 48 8d 88 b0 a3
RSP: 0018:ffffc9000bed6d30 EFLAGS: 00000002
RAX: 0000000000000ad0 RBX: ffff88807a5e0bc8 RCX: 0000000000000004
RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000000
RBP: ffff88807a5e0bd0 R08: ffffffff8173ef25 R09: ffffffff8df41cc0
R10: ffffc9000bed7038 R11: ffffffff81ad4ad0 R12: 0000000000000004
R13: ffff88807a5e0bd0 R14: ffff88807a5e0000 R15: 0000000000000003
FS: 00007f59943f46c0(0000) GS:ffff8881260b1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb82ebb7198 CR3: 000000008b648000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [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:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
unpoison_slab_object mm/kasan/common.c:342 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:368
kasan_slab_alloc include/linux/kasan.h:252 [inline]
slab_post_alloc_hook mm/slub.c:4948 [inline]
slab_alloc_node mm/slub.c:5258 [inline]
kmem_cache_alloc_noprof+0x367/0x6f0 mm/slub.c:5265
__kernfs_new_node+0xd7/0x7e0 fs/kernfs/dir.c:637
kernfs_new_node+0x102/0x210 fs/kernfs/dir.c:713
__kernfs_create_file+0x4b/0x2e0 fs/kernfs/file.c:1057
sysfs_add_file_mode_ns+0x238/0x300 fs/sysfs/file.c:313
create_files fs/sysfs/group.c:76 [inline]
internal_create_group+0x667/0x1110 fs/sysfs/group.c:183
internal_create_groups fs/sysfs/group.c:223 [inline]
sysfs_create_groups+0x59/0x120 fs/sysfs/group.c:249
setup_gid_attrs drivers/infiniband/core/sysfs.c:1162 [inline]
ib_setup_port_attrs+0x140c/0x2070 drivers/infiniband/core/sysfs.c:1439
add_one_compat_dev+0x3d6/0x5c0 drivers/infiniband/core/device.c:1005
rdma_dev_init_net+0x1dd/0x270 drivers/infiniband/core/device.c:1221
ops_init+0x35c/0x5c0 net/core/net_namespace.c:137
setup_net+0x110/0x330 net/core/net_namespace.c:446
copy_net_ns+0x3e3/0x570 net/core/net_namespace.c:581
create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130
unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:226
ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3128
__do_sys_unshare kernel/fork.c:3199 [inline]
__se_sys_unshare kernel/fork.c:3197 [inline]
__x64_sys_unshare+0x38/0x50 kernel/fork.c:3197
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f599358f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f59943f4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f59937e5fa0 RCX: 00007f599358f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062040200
RBP: 00007f5993613f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f59937e6038 R14: 00007f59937e5fa0 R15: 00007ffc5a1d2f48