INFO: task syz.1.18:6435 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18        state:D stack:25624 pid:6435  tgid:6433  ppid:6270   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5290 [inline]
 __schedule+0x14db/0x5030 kernel/sched/core.c:6902
 __schedule_loop kernel/sched/core.c:6984 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6999
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7056
 rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086
 __down_read_common kernel/locking/rwsem.c:1261 [inline]
 __down_read kernel/locking/rwsem.c:1274 [inline]
 down_read_nested+0x9b/0x2e0 kernel/locking/rwsem.c:1663
 dbAlloc+0x3a7/0xba0 fs/jfs/jfs_dmap.c:790
 diNewExt+0x9af/0x3150 fs/jfs/jfs_imap.c:2261
 diAllocExt fs/jfs/jfs_imap.c:1952 [inline]
 diAllocAG+0xe86/0x1df0 fs/jfs/jfs_imap.c:1669
 diAlloc+0x1d5/0x1680 fs/jfs/jfs_imap.c:1590
 ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56
 jfs_mkdir+0x193/0xa70 fs/jfs/namei.c:226
 vfs_mkdir+0x414/0x630 fs/namei.c:5231
 filename_mkdirat+0x27b/0x500 fs/namei.c:5264
 __do_sys_mkdirat fs/namei.c:5285 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5282
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9bab18efc9
RSP: 002b:00007f9babfb2038 EFLAGS: 00000246
 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f9bab3e5fa0 RCX: 00007f9bab18efc9
RDX: 0000000000000408 RSI: 0000200000000300 RDI: 0000000000000004
RBP: 00007f9bab211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9bab3e6038 R14: 00007f9bab3e5fa0 R15: 00007fffcd652988
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/u8:1/13:
 #0: 
ffff88801baa7148
 (
(wq_completion)netns
){+.+.}-{0:0}
, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
 #1: 
ffffc90000127c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x868/0x15a0 kernel/workqueue.c:3255
 #2: ffffffff8f50e530 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7a0 net/core/net_namespace.c:670
 #3: ffff8880315cf0e8
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:895 [inline]
, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506
 #4: 
ffff8880315cb250
 (
&devlink->lock_key
#15
){+.+.}-{4:4}
, at: devl_lock net/devlink/core.c:276 [inline]
, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506
 #5: 
ffffffff8f51be88
 (
rtnl_mutex
){+.+.}-{4:4}
, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1049 [inline]
, at: nsim_create+0x800/0x1050 drivers/net/netdevsim/netdev.c:1143
1 lock held by khungtaskd/30:
 #0: 
ffffffff8e144ce0
 (
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:2/35:
 #0: 
ffff88802f2a3148
 (
(wq_completion)ipv6_addrconf
){+.+.}-{0:0}
, at: process_one_work+0x841/0x15a0 kernel/workqueue.c:3254
 #1: 
ffffc90000ab7c40
 (
(work_completion)(&(&ifa->dad_work)->work)