------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: xprt_init_autodisconnect+0x0/0x230 net/sunrpc/xprt.c:193
WARNING: CPU: 0 PID: 32674 at lib/debugobjects.c:329 debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 32674 Comm: syz-executor3 Not tainted 4.17.0+ #39
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 panic+0x22f/0x4de kernel/panic.c:184
 __warn.cold.8+0x163/0x1b3 kernel/panic.c:536
 report_bug+0x252/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Code: 1a 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 92 00 00 00 48 8b 14 dd 60 75 1a 88 4c 89 f6 48 c7 c7 e0 6a 1a 88 e8 06 62 ec fd <0f> 0b 83 05 39 5b 44 06 01 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 
RSP: 0018:ffff8801dae077f8 EFLAGS: 00010086
RAX: 0000000000000065 RBX: 0000000000000003 RCX: ffffffff81854ed8
RDX: 0000000000000100 RSI: ffffffff8161f371 RDI: 0000000000000001
RBP: ffff8801dae07838 R08: ffff880195202580 R09: ffffed003b5c3ec2
R10: ffffed003b5c3ec2 R11: ffff8801dae1f617 R12: 0000000000000001
R13: ffffffff88f9a940 R14: ffffffff881a6f80 R15: ffffffff81677180
 __debug_check_no_obj_freed lib/debugobjects.c:783 [inline]
 debug_check_no_obj_freed+0x3a6/0x584 lib/debugobjects.c:815
 kfree+0xc7/0x260 mm/slab.c:3812
 __rcu_reclaim kernel/rcu/rcu.h:173 [inline]
 rcu_do_batch kernel/rcu/tree.c:2558 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2818 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2785 [inline]
 rcu_process_callbacks+0xfc5/0x1760 kernel/rcu/tree.c:2802
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364 [inline]
 irq_exit+0x1d1/0x200 kernel/softirq.c:404
 exiting_irq arch/x86/include/asm/apic.h:527 [inline]
 smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:debug_lockdep_rcu_enabled.part.1+0x1f/0x60 kernel/rcu/update.c:253
Code: 00 66 2e 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 65 48 8b 1c 25 40 ee 01 00 48 8d bb 34 08 00 00 <48> 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 
RSP: 0018:ffff8801ab4f6838 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff880195202580 RCX: 0000000000000000
RDX: 0000000000000004 RSI: ffff880195202db8 RDI: ffff880195202db4
RBP: ffff8801ab4f6840 R08: 0000000000000008 R09: 0000000000000001
R10: ffff880195202de0 R11: ffff880195202580 R12: ffffea000680b200
R13: ffffea000680b200 R14: ffff8801ab4f6b88 R15: 0000000000000000
 debug_lockdep_rcu_enabled+0x77/0x90 kernel/rcu/update.c:252
 rcu_read_lock+0x30/0x70 include/linux/rcupdate.h:632
 lock_page_memcg+0x6d/0x2f0 mm/memcontrol.c:1607
 page_remove_file_rmap mm/rmap.c:1214 [inline]
 page_remove_rmap+0x6ae/0x1250 mm/rmap.c:1299
 zap_pte_range mm/memory.c:1333 [inline]
 zap_pmd_range mm/memory.c:1437 [inline]
 zap_pud_range mm/memory.c:1466 [inline]
 zap_p4d_range mm/memory.c:1487 [inline]
 unmap_page_range+0xeb4/0x2200 mm/memory.c:1508
 unmap_single_vma+0x1a0/0x310 mm/memory.c:1553
 unmap_vmas+0x120/0x1f0 mm/memory.c:1583
 exit_mmap+0x2ba/0x5a0 mm/mmap.c:3105
 __mmput kernel/fork.c:962 [inline]
 mmput+0x251/0x610 kernel/fork.c:983
 exit_mm kernel/exit.c:544 [inline]
 do_exit+0xe98/0x2730 kernel/exit.c:852
 do_group_exit+0x16f/0x430 kernel/exit.c:968
 get_signal+0x886/0x1960 kernel/signal.c:2468
 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x2cf/0x360 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455a99
Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007f28150b6c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: fffffffffffffffb RBX: 00007f28150b76d4 RCX: 0000000000455a99
RDX: 000000002015d000 RSI: 0000000020343ff8 RDI: 0000000020144000
RBP: 000000000072bf48 R08: 000000002000a000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c1e89 R14: 00000000004cf510 R15: 0000000000000001

======================================================
WARNING: possible circular locking dependency detected
4.17.0+ #39 Not tainted
------------------------------------------------------
syz-executor3/32674 is trying to acquire lock:
000000009c3f3a38 ((console_sem).lock){-.-.}, at: down_trylock+0x13/0x70 kernel/locking/semaphore.c:136

but task is already holding lock:
0000000027188732 (&obj_hash[i].lock){-.-.}, at: __debug_check_no_obj_freed lib/debugobjects.c:774 [inline]
0000000027188732 (&obj_hash[i].lock){-.-.}, at: debug_check_no_obj_freed+0x159/0x584 lib/debugobjects.c:815

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&obj_hash[i].lock){-.-.}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
       __debug_object_init+0x11f/0x12c0 lib/debugobjects.c:381
       debug_object_init+0x16/0x20 lib/debugobjects.c:429
       debug_hrtimer_init kernel/time/hrtimer.c:410 [inline]
       debug_init kernel/time/hrtimer.c:458 [inline]
       hrtimer_init+0x8f/0x460 kernel/time/hrtimer.c:1308
       init_dl_task_timer+0x1b/0x50 kernel/sched/deadline.c:1056
       __sched_fork+0x2a8/0x570 kernel/sched/core.c:2184
       init_idle+0x75/0x7a0 kernel/sched/core.c:5404
       sched_init+0xbeb/0xd10 kernel/sched/core.c:6102
       start_kernel+0x475/0x92d init/main.c:602
       x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:452
       x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:433
       secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:242

-> #2 (&rq->lock){-.-.}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
       _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
       rq_lock kernel/sched/sched.h:1805 [inline]
       task_fork_fair+0x8a/0x660 kernel/sched/fair.c:9953
       sched_fork+0x43e/0xb30 kernel/sched/core.c:2380
       copy_process.part.38+0x1bf1/0x7180 kernel/fork.c:1765
       copy_process kernel/fork.c:1608 [inline]
       _do_fork+0x291/0x12a0 kernel/fork.c:2091
       kernel_thread+0x34/0x40 kernel/fork.c:2150
       rest_init+0x22/0xe4 init/main.c:408
       start_kernel+0x906/0x92d init/main.c:738
       x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:452
       x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:433
       secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:242

-> #1 (&p->pi_lock){-.-.}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
       try_to_wake_up+0xca/0x1280 kernel/sched/core.c:1984
       wake_up_process+0x10/0x20 kernel/sched/core.c:2147
       __up.isra.1+0x1b8/0x290 kernel/locking/semaphore.c:262
       up+0x12f/0x1b0 kernel/locking/semaphore.c:187
       __up_console_sem+0xbe/0x1b0 kernel/printk/printk.c:242
       console_unlock+0x79a/0x10a0 kernel/printk/printk.c:2411
       vprintk_emit+0x6b2/0xde0 kernel/printk/printk.c:1907
       vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
       vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
       printk+0x9e/0xba kernel/printk/printk.c:1981
       load_umh+0x51/0xbd net/bpfilter/bpfilter_kern.c:99
       do_one_initcall+0x127/0x913 init/main.c:884
       do_initcall_level init/main.c:952 [inline]
       do_initcalls init/main.c:960 [inline]
       do_basic_setup init/main.c:978 [inline]
       kernel_init_freeable+0x49b/0x58e init/main.c:1135
       kernel_init+0x11/0x1b3 init/main.c:1061
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412

-> #0 ((console_sem).lock){-.-.}:
       lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3924
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
       down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
       __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225
       console_trylock+0x15/0xa0 kernel/printk/printk.c:2230
       console_trylock_spinning kernel/printk/printk.c:1643 [inline]
       vprintk_emit+0x699/0xde0 kernel/printk/printk.c:1906
       vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
       vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
       printk+0x9e/0xba kernel/printk/printk.c:1981
       __warn_printk+0x83/0xd0 kernel/panic.c:590
       debug_print_object+0x16a/0x210 lib/debugobjects.c:326
       __debug_check_no_obj_freed lib/debugobjects.c:783 [inline]
       debug_check_no_obj_freed+0x3a6/0x584 lib/debugobjects.c:815
       kfree+0xc7/0x260 mm/slab.c:3812
       __rcu_reclaim kernel/rcu/rcu.h:173 [inline]
       rcu_do_batch kernel/rcu/tree.c:2558 [inline]
       invoke_rcu_callbacks kernel/rcu/tree.c:2818 [inline]
       __rcu_process_callbacks kernel/rcu/tree.c:2785 [inline]
       rcu_process_callbacks+0xfc5/0x1760 kernel/rcu/tree.c:2802
       __do_softirq+0x2e0/0xaf5 kernel/softirq.c:284
       invoke_softirq kernel/softirq.c:364 [inline]
       irq_exit+0x1d1/0x200 kernel/softirq.c:404
       exiting_irq arch/x86/include/asm/apic.h:527 [inline]
       smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052
       apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
       debug_lockdep_rcu_enabled.part.1+0x1f/0x60 kernel/rcu/update.c:253
       debug_lockdep_rcu_enabled+0x77/0x90 kernel/rcu/update.c:252
       rcu_read_lock+0x30/0x70 include/linux/rcupdate.h:632
       lock_page_memcg+0x6d/0x2f0 mm/memcontrol.c:1607
       page_remove_file_rmap mm/rmap.c:1214 [inline]
       page_remove_rmap+0x6ae/0x1250 mm/rmap.c:1299
       zap_pte_range mm/memory.c:1333 [inline]
       zap_pmd_range mm/memory.c:1437 [inline]
       zap_pud_range mm/memory.c:1466 [inline]
       zap_p4d_range mm/memory.c:1487 [inline]
       unmap_page_range+0xeb4/0x2200 mm/memory.c:1508
       unmap_single_vma+0x1a0/0x310 mm/memory.c:1553
       unmap_vmas+0x120/0x1f0 mm/memory.c:1583
       exit_mmap+0x2ba/0x5a0 mm/mmap.c:3105
       __mmput kernel/fork.c:962 [inline]
       mmput+0x251/0x610 kernel/fork.c:983
       exit_mm kernel/exit.c:544 [inline]
       do_exit+0xe98/0x2730 kernel/exit.c:852
       do_group_exit+0x16f/0x430 kernel/exit.c:968
       get_signal+0x886/0x1960 kernel/signal.c:2468
       do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816
       exit_to_usermode_loop+0x2cf/0x360 arch/x86/entry/common.c:162
       prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
       syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
       do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
  (console_sem).lock --> &rq->lock --> &obj_hash[i].lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&obj_hash[i].lock);
                               lock(&rq->lock);
                               lock(&obj_hash[i].lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

4 locks held by syz-executor3/32674:
 #0: 000000002ba7acf6 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline]
 #0: 000000002ba7acf6 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_pte_range mm/memory.c:1294 [inline]
 #0: 000000002ba7acf6 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_pmd_range mm/memory.c:1437 [inline]
 #0: 000000002ba7acf6 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_pud_range mm/memory.c:1466 [inline]
 #0: 000000002ba7acf6 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_p4d_range mm/memory.c:1487 [inline]
 #0: 000000002ba7acf6 (&(ptlock_ptr(page))->rlock#2){+.+.}, at: unmap_page_range+0x99b/0x2200 mm/memory.c:1508
 #1: 000000005ce3c393 (rcu_read_lock){....}, at: rcu_read_lock+0x0/0x70 include/linux/compiler.h:188
 #2: 00000000f3371f18 (rcu_callback){....}, at: __rcu_reclaim kernel/rcu/rcu.h:168 [inline]
 #2: 00000000f3371f18 (rcu_callback){....}, at: rcu_do_batch kernel/rcu/tree.c:2558 [inline]
 #2: 00000000f3371f18 (rcu_callback){....}, at: invoke_rcu_callbacks kernel/rcu/tree.c:2818 [inline]
 #2: 00000000f3371f18 (rcu_callback){....}, at: __rcu_process_callbacks kernel/rcu/tree.c:2785 [inline]
 #2: 00000000f3371f18 (rcu_callback){....}, at: rcu_process_callbacks+0xf88/0x1760 kernel/rcu/tree.c:2802
 #3: 0000000027188732 (&obj_hash[i].lock){-.-.}, at: __debug_check_no_obj_freed lib/debugobjects.c:774 [inline]
 #3: 0000000027188732 (&obj_hash[i].lock){-.-.}, at: debug_check_no_obj_freed+0x159/0x584 lib/debugobjects.c:815

stack backtrace:
CPU: 0 PID: 32674 Comm: syz-executor3 Not tainted 4.17.0+ #39
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 print_circular_bug.isra.36.cold.56+0x1bd/0x27d kernel/locking/lockdep.c:1227
 check_prev_add kernel/locking/lockdep.c:1867 [inline]
 check_prevs_add kernel/locking/lockdep.c:1980 [inline]
 validate_chain kernel/locking/lockdep.c:2421 [inline]
 __lock_acquire+0x343e/0x5140 kernel/locking/lockdep.c:3435
 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3924
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
 down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
 __down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225
 console_trylock+0x15/0xa0 kernel/printk/printk.c:2230
 console_trylock_spinning kernel/printk/printk.c:1643 [inline]
 vprintk_emit+0x699/0xde0 kernel/printk/printk.c:1906
 vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
 vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
 printk+0x9e/0xba kernel/printk/printk.c:1981
 __warn_printk+0x83/0xd0 kernel/panic.c:590
 debug_print_object+0x16a/0x210 lib/debugobjects.c:326
 __debug_check_no_obj_freed lib/debugobjects.c:783 [inline]
 debug_check_no_obj_freed+0x3a6/0x584 lib/debugobjects.c:815
 kfree+0xc7/0x260 mm/slab.c:3812
 __rcu_reclaim kernel/rcu/rcu.h:173 [inline]
 rcu_do_batch kernel/rcu/tree.c:2558 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2818 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2785 [inline]
 rcu_process_callbacks+0xfc5/0x1760 kernel/rcu/tree.c:2802
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364 [inline]
 irq_exit+0x1d1/0x200 kernel/softirq.c:404
 exiting_irq arch/x86/include/asm/apic.h:527 [inline]
 smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:debug_lockdep_rcu_enabled.part.1+0x1f/0x60 kernel/rcu/update.c:253
Code: 00 66 2e 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 65 48 8b 1c 25 40 ee 01 00 48 8d bb 34 08 00 00 <48> 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 
RSP: 0018:ffff8801ab4f6838 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff880195202580 RCX: 0000000000000000
RDX: 0000000000000004 RSI: ffff880195202db8 RDI: ffff880195202db4
RBP: ffff8801ab4f6840 R08: 0000000000000008 R09: 0000000000000001
R10: ffff880195202de0 R11: ffff880195202580 R12: ffffea000680b200
R13: ffffea000680b200 R14: ffff8801ab4f6b88 R15: 0000000000000000
 debug_lockdep_rcu_enabled+0x77/0x90 kernel/rcu/update.c:252
 rcu_read_lock+0x30/0x70 include/linux/rcupdate.h:632
 lock_page_memcg+0x6d/0x2f0 mm/memcontrol.c:1607
 page_remove_file_rmap mm/rmap.c:1214 [inline]
 page_remove_rmap+0x6ae/0x1250 mm/rmap.c:1299
Lost 172 message(s)!
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..