INFO: task syz.5.321:7926 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.321       state:D stack:22656 pid:7926  tgid:7925  ppid:7816   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 drop_caches_sysctl_handler+0x97/0x170
 proc_sys_call_handler+0x4c8/0x830
 do_iter_readv_writev+0x619/0x8c0
 vfs_writev+0x33c/0x990
 do_writev+0x154/0x2e0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2dee79c819
RSP: 002b:00007f2def5fb028 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f2deea15fa0 RCX: 00007f2dee79c819
RDX: 0000000000000001 RSI: 0000200000000080 RDI: 0000000000000009
RBP: 00007f2dee832c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2deea16038 R14: 00007f2deea15fa0 R15: 00007ffe8ace3258
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
 #0: ffff8881012ae148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0
 #1: ffffc90000117c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0
 #2: ffffffff8fbc2f90 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffff888110625568 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x310
1 lock held by khungtaskd/36:
 #0: ffffffff8e75e620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
1 lock held by dhcpcd/5555:
2 locks held by getty/5634:
 #0: ffff8881769f70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
2 locks held by syz-executor/5811:
3 locks held by syz.5.321/7926:
 #0: ffff88816f41b2f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320
 #1: ffff8881b0ca8420 (sb_writers#3){.+.+}-{0:0}, at: vfs_writev+0x2aa/0x990
 #2: ffff8881742a00e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.9.667/10345:
 #0: ffff8881742a00e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
7 locks held by syz-executor/11208:
 #0: ffff88817570e420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff888113c0c088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88816b929878 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f445688 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
 #4: ffff8881685d0130 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870
 #5: ffff8881b33e7250 (&devlink->lock_key#7){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170
 #6: ffffffff8e764780 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580
4 locks held by syz-executor/11238:
 #0: ffff88817570e420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff8881a95a2088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88816b929878 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f445688 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
4 locks held by syz-executor/11259:
 #0: ffff88817570e420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff8881a68ed088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff88816b929878 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f445688 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
2 locks held by dhcpcd-run-hook/11327:

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 36 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11328 Comm: cmp Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:kasan_check_range+0x1cc/0x2c0
Code: 01 f3 49 8d 5c 24 07 4d 85 e4 49 0f 49 dc 48 83 e3 f8 49 29 dc 74 0e 41 80 3b 00 75 7c 49 ff c3 49 ff cc 75 f2 5b 41 5c 41 5d <41> 5e 41 5f 5d e9 8a 86 80 09 cc 45 84 ff 0f 85 a1 00 00 00 41 f7
RSP: 0018:ffffc90004aff800 EFLAGS: 00000297
RAX: ffffffff8ba5c501 RBX: ffff8881134949c0 RCX: ffffffff8ba5c5ec
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff9a7ee900
RBP: ffffc90004affa10 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff34fdd20 R12: ffff8881b07a1680
R13: dffffc0000000000 R14: fffffbfff34fdd21 R15: 1ffffffff34fdd20
FS:  00007fd474ab6380(0000) GS:ffff8882a9462000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd474b3119c CR3: 00000001aae88000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 mt_validate+0x3c5c/0x41f0
 validate_mm+0xd4/0x4c0
 do_brk_flags+0x7aa/0x9b0
 __se_sys_brk+0x9d8/0xba0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd474c0ec7c
Code: 1a 64 c7 03 01 00 00 00 eb 11 64 44 89 23 31 f6 5b 31 ff 5d 41 5c e9 41 ff ff ff 5b 83 c8 ff 5d 41 5c c3 b8 0c 00 00 00 0f 05 <48> 8b 15 d5 61 0d 00 45 31 c0 48 89 02 48 39 c7 76 12 48 8b 05 73
RSP: 002b:00007ffc1f19a7e8 EFLAGS: 00000206 ORIG_RAX: 000000000000000c
RAX: ffffffffffffffda RBX: 0000000000021000 RCX: 00007fd474c0ec7c
RDX: 00007fd474ced1b8 RSI: 00007fd474ce5b00 RDI: 00005653e088e000
RBP: 00007fd474ce5aa0 R08: 0000000000000000 R09: 00007fd474ce5d80
R10: 0000000000000037 R11: 0000000000000206 R12: 00005653e086d000
R13: 0000000000000290 R14: 0000000000001000 R15: 0000000000000000
 </TASK>
