INFO: task syz-executor:6903 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:20264 pid:6903  tgid:6903  ppid:1      task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 v9fs_evict_inode+0x170/0x320
 evict+0x504/0x9c0
 __dentry_kill+0x209/0x660
 dput+0x19f/0x2b0
 shrink_dcache_for_umount+0xa0/0x170
 generic_shutdown_super+0x67/0x2c0
 kill_anon_super+0x3b/0x70
 v9fs_kill_super+0x4c/0x90
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f538798ff17
RSP: 002b:00007ffd8ffbab08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f5387a11c05 RCX: 00007f538798ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd8ffbabc0
RBP: 00007ffd8ffbabc0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd8ffbbc50
R13: 00007f5387a11c05 R14: 000000000001fa5c R15: 00007ffd8ffbbc90
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/u10:5/1091:
 #0: ffff888136639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
 #1: ffff888136624008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
 #2: ffff8881366269d8 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30
4 locks held by kworker/u10:6/1092:
2 locks held by getty/5681:
 #0: ffff888022dc20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by syz-executor/6903:
 #0: ffff8881061600e0 (&type->s_umount_key#83){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0
4 locks held by syz.2.736/10474:
1 lock held by syz.4.737/10479:
2 locks held by dhcpcd/10489:
 #0: ffff88803f054258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0
 #1: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 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: 5595 Comm: dhcpcd 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:sched_ttwu_pending+0x2b5/0x6e0
Code: 01 00 00 48 8b 44 24 18 3b 18 0f 85 8d 00 00 00 49 81 c7 58 05 00 00 4c 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 26 01 00 00 <41> 8b 17 c1 e2 05 83 e2 20 4c 89 ef 4c 89 f6 48 8d 4c 24 50 e8 22
RSP: 0018:ffffc900001e0e40 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 1ffff11026cc7575
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc900001e0f60 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200003c1b0 R12: ffff888136639f80
R13: ffff888136639f80 R14: ffff88810cfcb980 R15: ffff88810cfcbf10
FS:  00007fc3a9536740(0000) GS:ffff8881a3c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffee6d84308 CR3: 0000000023f3a000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 __flush_smp_call_function_queue+0x86d/0xaa0
 __sysvec_call_function_single+0xa8/0x3d0
 sysvec_call_function_single+0x9e/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x1a/0x20
RIP: 0010:kasan_check_range+0xd/0x2c0
Code: 0f 0b cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 41 56 41 55 41 54 <53> b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37 49 39 f8 0f 82 82
RSP: 0018:ffffc90002c8ede8 EFLAGS: 00000246
RAX: 1ffff92000591de8 RBX: 0000000000000010 RCX: ffffffff8172cd88
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90002c8ef58
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff8172c195
R10: ffffc90002c8ef58 R11: ffffffff81ac3aa0 R12: ffffc90002c8f310
R13: ffffc90002c8ef58 R14: ffffc90002c8ef58 R15: ffffc90002c8ef50
 __asan_memset+0x22/0x50
 unwind_next_frame+0xc98/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 ptlock_alloc+0x20/0x70
 pte_alloc_one+0x7d/0x170
 __pte_alloc+0x25/0x1a0
 copy_pmd_range+0x6a91/0x71d0
 copy_page_range+0xc14/0x1270
 dup_mmap+0xf57/0x1ac0
 copy_mm+0x13c/0x4b0
 copy_process+0x1706/0x3c00
 kernel_clone+0x21e/0x840
 __x64_sys_clone+0x18b/0x1e0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc3a95e6a12
Code: 41 5d 41 5e 41 5f c3 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 e7 43 0f 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffee6d639d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 000055b4dfc26f01 RCX: 00007fc3a95e6a12
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffee6d83f48 R08: 0000000000000000 R09: 000055b4dfc26f80
R10: 00007fc3a9536a10 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 000055b4dfc26fb4
 </TASK>
