TITLE: possible deadlock in test_clear_page_writeback
TYPE: LOCKDEP

[  904.288838] =====================================================
[  904.295086] WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
[  904.301824] 4.14.176-syzkaller #0 Not tainted
[  904.306294] -----------------------------------------------------
[  904.312502] syz-executor.5/31323 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
[  904.319976]  (&(&info->lock)->rlock){+.+.}, at: [<ffffffff8174eed4>] shmem_uncharge+0x24/0x250
[  904.328729] 
[  904.328729] and this task is already holding:
[  904.334745]  (&(&mapping->tree_lock)->rlock){-.-.}, at: [<ffffffff81861f78>] split_huge_page_to_list+0x548/0x1f40
[  904.345139] which would create a new lock dependency:
[  904.350317]  (&(&mapping->tree_lock)->rlock){-.-.} -> (&(&info->lock)->rlock){+.+.}
[  904.358112] 
[  904.358112] but this new dependency connects a HARDIRQ-irq-safe lock:
[  904.366338]  (&(&mapping->tree_lock)->rlock){-.-.}
[  904.366344] 
[  904.366344] ... which became HARDIRQ-irq-safe at:
[  904.377852]   lock_acquire+0x170/0x3f0
[  904.381733]   _raw_spin_lock_irqsave+0x8c/0xbf
[  904.386298]   test_clear_page_writeback+0x199/0xc20
[  904.391349]   end_page_writeback+0xe4/0x210
[  904.395728]   ext4_finish_bio+0x483/0x710
[  904.399862]   ext4_end_bio+0x14b/0x5a0
[  904.403740]   bio_endio+0x315/0x670
[  904.407359]   blk_update_request+0x27a/0x9d0
[  904.411804]   scsi_end_request+0x7d/0x9b0
[  904.416112]   scsi_io_completion+0xa63/0x1590
[  904.420604]   scsi_softirq_done+0x2c8/0x360
[  904.424912]   __blk_mq_complete_request+0x30b/0x6c0
[  904.429929]   blk_mq_complete_request+0x51/0x60
[  904.434694]   virtscsi_vq_done+0xa7/0x130
[  904.438990]   vring_interrupt+0x101/0x150
[  904.443147]   __handle_irq_event_percpu+0x125/0x7e0
[  904.448217]   handle_irq_event_percpu+0x66/0x120
[  904.452954]   handle_irq_event+0xa2/0x12d
[  904.457111]   handle_edge_irq+0x215/0x810
[  904.461395]   handle_irq+0x35/0x50
[  904.464919]   do_IRQ+0x93/0x1d0
[  904.468190]   ret_from_intr+0x0/0x1e
[  904.471935] 
[  904.471935] to a HARDIRQ-irq-unsafe lock:
[  904.477645]  (&(&info->lock)->rlock){+.+.}
[  904.477653] 
[  904.477653] ... which became HARDIRQ-irq-unsafe at:
[  904.488344] ...
[  904.488359]   lock_acquire+0x170/0x3f0
[  904.494125]   _raw_spin_lock+0x2a/0x40
[  904.498006]   shmem_mfill_atomic_pte+0x11ba/0x1790
[  904.502930]   shmem_mfill_zeropage_pte+0x81/0xa0
[  904.507744]   mfill_zeropage+0x773/0xcd0
[  904.511813]   userfaultfd_ioctl+0x10da/0x2f80
[  904.516315]   do_vfs_ioctl+0x75a/0xfe0
[  904.520199]   SyS_ioctl+0x7f/0xb0
[  904.523639]   do_syscall_64+0x1d5/0x640
[  904.527605]   entry_SYSCALL_64_after_hwframe+0x42/0xb7
[  904.532858] 
[  904.532858] other info that might help us debug this:
[  904.532858] 
[  904.540987]  Possible interrupt unsafe locking scenario:
[  904.540987] 
[  904.547896]        CPU0                    CPU1
[  904.552540]        ----                    ----
[  904.557236]   lock(&(&info->lock)->rlock);
[  904.561582]                                local_irq_disable();
[  904.567666]                                lock(&(&mapping->tree_lock)->rlock);
[  904.575191]                                lock(&(&info->lock)->rlock);
[  904.582033]   <Interrupt>
[  904.585029]     lock(&(&mapping->tree_lock)->rlock);
[  904.590127] 
[  904.590127]  *** DEADLOCK ***
[  904.590127] 
[  904.596165] 5 locks held by syz-executor.5/31323:
[  904.600980]  #0:  (shrinker_rwsem){++++}, at: [<ffffffff81723230>] shrink_slab.part.0+0xb0/0xa50
[  904.609892]  #1:  (&type->s_umount_key#34){++++}, at: [<ffffffff818bbcfb>] trylock_super+0x1b/0xe0
[  904.618970]  #2:  (&mapping->i_mmap_rwsem){++++}, at: [<ffffffff81861cbd>] split_huge_page_to_list+0x28d/0x1f40
[  904.629176]  #3:  (&(&pgdat->lru_lock)->rlock){-.-.}, at: [<ffffffff81861f59>] split_huge_page_to_list+0x529/0x1f40
[  904.639738]  #4:  (&(&mapping->tree_lock)->rlock){-.-.}, at: [<ffffffff81861f78>] split_huge_page_to_list+0x548/0x1f40
[  904.650552] 
[  904.650552] the dependencies between HARDIRQ-irq-safe lock and the holding lock:
[  904.659569] -> (&(&mapping->tree_lock)->rlock){-.-.} ops: 1157811 {
[  904.665972]    IN-HARDIRQ-W at:
[  904.669244]                     lock_acquire+0x170/0x3f0
[  904.674674]                     _raw_spin_lock_irqsave+0x8c/0xbf
[  904.680799]                     test_clear_page_writeback+0x199/0xc20
[  904.687353]                     end_page_writeback+0xe4/0x210
[  904.693231]                     ext4_finish_bio+0x483/0x710
[  904.698943]                     ext4_end_bio+0x14b/0x5a0
[  904.705208]                     bio_endio+0x315/0x670
[  904.710532]                     blk_update_request+0x27a/0x9d0
[  904.716487]                     scsi_end_request+0x7d/0x9b0
[  904.722177]                     scsi_io_completion+0xa63/0x1590
[  904.728212]                     scsi_softirq_done+0x2c8/0x360
[  904.734074]                     __blk_mq_complete_request+0x30b/0x6c0
[  904.740649]                     blk_mq_complete_request+0x51/0x60
[  904.746877]                     virtscsi_vq_done+0xa7/0x130
[  904.752695]                     vring_interrupt+0x101/0x150
[  904.758388]                     __handle_irq_event_percpu+0x125/0x7e0
[  904.765033]                     handle_irq_event_percpu+0x66/0x120
[  904.771358]                     handle_irq_event+0xa2/0x12d
[  904.777085]                     handle_edge_irq+0x215/0x810
[  904.782879]                     handle_irq+0x35/0x50
[  904.787969]                     do_IRQ+0x93/0x1d0
[  904.792899]                     ret_from_intr+0x0/0x1e
[  904.798155]    IN-SOFTIRQ-W at:
[  904.801447]                     lock_acquire+0x170/0x3f0
[  904.806881]                     _raw_spin_lock_irqsave+0x8c/0xbf
[  904.813006]                     test_clear_page_writeback+0x199/0xc20
[  904.819577]                     end_page_writeback+0xe4/0x210
[  904.825441]                     end_buffer_async_write+0x367/0x6a0
[  904.831752]                     end_bio_bh_io_sync+0xbf/0x100
[  904.837627]                     bio_endio+0x315/0x670
[  904.842794]                     blk_update_request+0x27a/0x9d0
[  904.848758]                     scsi_end_request+0x7d/0x9b0
[  904.854449]                     scsi_io_completion+0xa63/0x1590
[  904.860491]                     scsi_softirq_done+0x2c8/0x360
[  904.866354]                     __blk_mq_complete_request+0x30b/0x6c0
[  904.872909]                     blk_mq_complete_request+0x51/0x60
[  904.879136]                     virtscsi_vq_done+0xa7/0x130
[  904.884831]                     vring_interrupt+0x101/0x150
[  904.890533]                     __handle_irq_event_percpu+0x125/0x7e0
[  904.897086]                     handle_irq_event_percpu+0x66/0x120
[  904.903381]                     handle_irq_event+0xa2/0x12d
[  904.909068]                     handle_edge_irq+0x215/0x810
[  904.914755]                     handle_irq+0x35/0x50
[  904.919853]                     do_IRQ+0x93/0x1d0
[  904.924690]                     ret_from_intr+0x0/0x1e
[  904.930063]                     kfree+0xf4/0x260
[  904.934812]                     skb_free_head+0x83/0xa0
[  904.940809]                     skb_release_data+0x528/0x7b0
[  904.946616]                     skb_release_all+0x46/0x60
[  904.952140]                     consume_skb+0xa7/0x330
[  904.957427]                     __dev_kfree_skb_any+0x7a/0xa0
[  904.963335]                     free_old_xmit_skbs.isra.0+0x178/0x2a0
[  904.969916]                     start_xmit+0x148/0x1400
[  904.975275]                     dev_hard_start_xmit+0x186/0x890
[  904.981383]                     sch_direct_xmit+0x25f/0x510
[  904.987085]                     __dev_queue_xmit+0x1b6e/0x25c0
[  904.993048]                     ip_finish_output2+0xde8/0x14a0
[  904.999009]                     ip_finish_output+0x556/0xc30
[  905.004782]                     ip_output+0x1c2/0x520
[  905.009962]                     ip_local_out+0x93/0x170
[  905.016864]                     ip_queue_xmit+0x7b2/0x1b20
[  905.022465]                     __tcp_transmit_skb+0x1654/0x2dd0
[  905.028585]                     __tcp_send_ack.part.0+0x3ab/0x5a0
[  905.034792]                     tcp_send_ack+0x6f/0x90
[  905.040048]                     __tcp_ack_snd_check+0xf6/0x380
[  905.046005]                     tcp_rcv_established+0x1122/0x15d0
[  905.052222]                     tcp_v4_do_rcv+0x55d/0x7e0
[  905.057759]                     tcp_v4_rcv+0x25ac/0x3250
[  905.063210]                     ip_local_deliver_finish+0x245/0xaa0
[  905.069593]                     ip_local_deliver+0x1a6/0x450
[  905.075378]                     ip_rcv_finish+0x79b/0x1a10
[  905.080990]                     ip_rcv+0x9d8/0xfec
[  905.085897]                     __netif_receive_skb_core+0x1e50/0x2c00
[  905.092537]                     __netif_receive_skb+0x27/0x1a0
[  905.098496]                     netif_receive_skb_internal+0xd7/0x580
[  905.105067]                     napi_gro_receive+0x2ed/0x410
[  905.110844]                     receive_buf+0x4e6/0x4480
[  905.116284]                     virtnet_poll+0x4d3/0x9b3
[  905.121719]                     net_rx_action+0x456/0xe90
[  905.127349]                     __do_softirq+0x254/0x9bf
[  905.132783]                     irq_exit+0x15b/0x1a0
[  905.137868]                     do_IRQ+0x112/0x1d0
[  905.142806]                     ret_from_intr+0x0/0x1e
[  905.148059]                     native_safe_halt+0xe/0x10
[  905.153593]                     default_idle+0x47/0x370
[  905.158932]                     do_idle+0x250/0x3c0
[  905.163924]                     cpu_startup_entry+0x14/0x20
[  905.169636]                     start_kernel+0x659/0x676
[  905.175063]                     secondary_startup_64+0xa5/0xb0
[  905.181015]    INITIAL USE at:
[  905.184206]                    lock_acquire+0x170/0x3f0
[  905.189555]                    _raw_spin_lock_irq+0x5b/0x80
[  905.195260]                    __add_to_page_cache_locked+0x286/0x870
[  905.201825]                    add_to_page_cache_lru+0xe9/0x300
[  905.207867]                    do_read_cache_page+0x6d5/0x12a0
[  905.213829]                    read_dev_sector+0xbf/0x3d0
[  905.219392]                    adfspart_check_ICS+0xf3/0xc10
[  905.225168]                    check_partition+0x33f/0x62d
[  905.230768]                    rescan_partitions+0x1e5/0x850
[  905.236541]                    __blkdev_get+0x926/0x10d0
[  905.241967]                    blkdev_get+0x84/0x8a0
[  905.247058]                    device_add_disk+0x897/0xd80
[  905.252657]                    brd_init+0x214/0x3c9
[  905.257648]                    do_one_initcall+0x88/0x202
[  905.263164]                    kernel_init_freeable+0x465/0x526
[  905.269210]                    kernel_init+0xd/0x15b
[  905.274300]                    ret_from_fork+0x24/0x30
[  905.279548]  }
[  905.281329]  ... key      at: [<ffffffff8a5a8020>] __key.49022+0x0/0x40
[  905.288051]  ... acquired at:
[  905.291137]    lock_acquire+0x170/0x3f0
[  905.295087]    _raw_spin_lock_irqsave+0x8c/0xbf
[  905.299753]    shmem_uncharge+0x24/0x250
[  905.303789]    split_huge_page_to_list+0x1590/0x1f40
[  905.308882]    shmem_unused_huge_shrink+0x5ca/0x1180
[  905.313963]    shmem_unused_huge_scan+0x70/0xa0
[  905.318619]    super_cache_scan+0x333/0x460
[  905.322926]    shrink_slab.part.0+0x3bb/0xa50
[  905.327475]    shrink_node+0x848/0xb60
[  905.331471]    do_try_to_free_pages+0x357/0xe80
[  905.336124]    try_to_free_pages+0x233/0x6e0
[  905.340515]    __alloc_pages_slowpath+0x91d/0x26c0
[  905.345468]    __alloc_pages_nodemask+0x5d3/0x700
[  905.350289]    alloc_pages_current+0xe7/0x1e0
[  905.354763]    kvm_mmu_create+0xd1/0x1c0
[  905.358801]    kvm_arch_vcpu_init+0x28b/0x8b0
[  905.363288]    kvm_vcpu_init+0x26d/0x360
[  905.367329]    vmx_create_vcpu+0xf3/0x2900
[  905.371541]    kvm_vm_ioctl+0x49c/0x1430
[  905.375580]    do_vfs_ioctl+0x75a/0xfe0
[  905.379530]    SyS_ioctl+0x7f/0xb0
[  905.383064]    do_syscall_64+0x1d5/0x640
[  905.387119]    entry_SYSCALL_64_after_hwframe+0x42/0xb7
[  905.392453] 
[  905.394064] 
[  905.394064] the dependencies between the lock to be acquired
[  905.394068]  and HARDIRQ-irq-unsafe lock:
[  905.405774] -> (&(&info->lock)->rlock){+.+.} ops: 96687 {
[  905.411300]    HARDIRQ-ON-W at:
[  905.414568]                     lock_acquire+0x170/0x3f0
[  905.420112]                     _raw_spin_lock+0x2a/0x40
[  905.425551]                     shmem_mfill_atomic_pte+0x11ba/0x1790
[  905.432021]                     shmem_mfill_zeropage_pte+0x81/0xa0
[  905.438316]                     mfill_zeropage+0x773/0xcd0
[  905.443940]                     userfaultfd_ioctl+0x10da/0x2f80
[  905.450114]                     do_vfs_ioctl+0x75a/0xfe0
[  905.455684]                     SyS_ioctl+0x7f/0xb0
[  905.460706]                     do_syscall_64+0x1d5/0x640
[  905.466224]                     entry_SYSCALL_64_after_hwframe+0x42/0xb7
[  905.473038]    SOFTIRQ-ON-W at:
[  905.476299]                     lock_acquire+0x170/0x3f0
[  905.481726]                     _raw_spin_lock+0x2a/0x40
[  905.487165]                     shmem_mfill_atomic_pte+0x11ba/0x1790
[  905.493633]                     shmem_mfill_zeropage_pte+0x81/0xa0
[  905.499946]                     mfill_zeropage+0x773/0xcd0
[  905.505574]                     userfaultfd_ioctl+0x10da/0x2f80
[  905.511615]                     do_vfs_ioctl+0x75a/0xfe0
[  905.517055]                     SyS_ioctl+0x7f/0xb0
[  905.522054]                     do_syscall_64+0x1d5/0x640
[  905.527569]                     entry_SYSCALL_64_after_hwframe+0x42/0xb7
[  905.534382]    INITIAL USE at:
[  905.537557]                    lock_acquire+0x170/0x3f0
[  905.542912]                    _raw_spin_lock_irq+0x5b/0x80
[  905.548616]                    shmem_getpage_gfp+0x17c6/0x2790
[  905.554573]                    shmem_write_begin+0xf4/0x190
[  905.560376]                    generic_perform_write+0x1c9/0x420
[  905.566557]                    __generic_file_write_iter+0x227/0x590
[  905.573034]                    generic_file_write_iter+0x2fa/0x650
[  905.579333]                    __vfs_write+0x44e/0x630
[  905.584724]                    vfs_write+0x192/0x4e0
[  905.589822]                    SyS_write+0xf2/0x210
[  905.594833]                    do_syscall_64+0x1d5/0x640
[  905.600414]                    entry_SYSCALL_64_after_hwframe+0x42/0xb7
[  905.607146]  }
[  905.608932]  ... key      at: [<ffffffff8a5968c0>] __key.49220+0x0/0x40
[  905.615780]  ... acquired at:
[  905.618866]    lock_acquire+0x170/0x3f0
[  905.622899]    _raw_spin_lock_irqsave+0x8c/0xbf
[  905.627544]    shmem_uncharge+0x24/0x250
[  905.631581]    split_huge_page_to_list+0x1590/0x1f40
[  905.636661]    shmem_unused_huge_shrink+0x5ca/0x1180
[  905.641746]    shmem_unused_huge_scan+0x70/0xa0
[  905.646390]    super_cache_scan+0x333/0x460
[  905.650705]    shrink_slab.part.0+0x3bb/0xa50
[  905.655193]    shrink_node+0x848/0xb60
[  905.659057]    do_try_to_free_pages+0x357/0xe80
[  905.663701]    try_to_free_pages+0x233/0x6e0
[  905.668102]    __alloc_pages_slowpath+0x91d/0x26c0
[  905.673024]    __alloc_pages_nodemask+0x5d3/0x700
[  905.677843]    alloc_pages_current+0xe7/0x1e0
[  905.682313]    kvm_mmu_create+0xd1/0x1c0
[  905.686350]    kvm_arch_vcpu_init+0x28b/0x8b0
[  905.690837]    kvm_vcpu_init+0x26d/0x360
[  905.694874]    vmx_create_vcpu+0xf3/0x2900
[  905.699084]    kvm_vm_ioctl+0x49c/0x1430
[  905.703123]    do_vfs_ioctl+0x75a/0xfe0
[  905.707071]    SyS_ioctl+0x7f/0xb0
[  905.710585]    do_syscall_64+0x1d5/0x640
[  905.714621]    entry_SYSCALL_64_after_hwframe+0x42/0xb7
[  905.719966] 
[  905.721574] 
[  905.721574] stack backtrace:
[  905.726064] CPU: 0 PID: 31323 Comm: syz-executor.5 Not tainted 4.14.176-syzkaller #0
[  905.736891] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[  905.746233] Call Trace:
[  905.748808]  dump_stack+0x13e/0x194
[  905.752418]  check_usage.cold+0x60e/0x97b
[  905.756665]  ? unwind_next_frame+0xbc6/0x17a0
[  905.761160]  ? check_usage_forwards+0x300/0x300
[  905.765828]  ? unwind_next_frame+0xbc6/0x17a0
[  905.770395]  ? bpf_prog_kallsyms_find+0x36/0x260
[  905.775204]  ? __kernel_text_address+0x9/0x30
[  905.779701]  ? unwind_get_return_address+0x5a/0xa0
[  905.784622]  ? __lock_acquire+0x1d77/0x4620
[  905.788927]  __lock_acquire+0x1d77/0x4620
[  905.793081]  ? trace_hardirqs_on+0x10/0x10
[  905.797294]  ? delete_node+0x1ed/0x680
[  905.801160]  ? check_preemption_disabled+0x35/0x240
[  905.806157]  ? __mod_node_page_state+0x89/0xd0
[  905.810720]  lock_acquire+0x170/0x3f0
[  905.814495]  ? shmem_uncharge+0x24/0x250
[  905.818549]  _raw_spin_lock_irqsave+0x8c/0xbf
[  905.823050]  ? shmem_uncharge+0x24/0x250
[  905.827104]  shmem_uncharge+0x24/0x250
[  905.830970]  split_huge_page_to_list+0x1590/0x1f40
[  905.835880]  ? can_split_huge_page+0x2b0/0x2b0
[  905.840439]  shmem_unused_huge_shrink+0x5ca/0x1180
[  905.845359]  ? shmem_write_end+0x6e0/0x6e0
[  905.849624]  ? prune_icache_sb+0xcf/0x120
[  905.853775]  shmem_unused_huge_scan+0x70/0xa0
[  905.858318]  super_cache_scan+0x333/0x460
[  905.862453]  shrink_slab.part.0+0x3bb/0xa50
[  905.866775]  ? current_may_throttle+0x210/0x210
[  905.871423]  ? mem_cgroup_iter+0x393/0x620
[  905.875636]  shrink_node+0x848/0xb60
[  905.879329]  ? shrink_node_memcg+0x12b0/0x12b0
[  905.883887]  ? ktime_get+0x1b4/0x2c0
[  905.887580]  do_try_to_free_pages+0x357/0xe80
[  905.892060]  ? shrink_node+0xb60/0xb60
[  905.895940]  try_to_free_pages+0x233/0x6e0
[  905.900164]  ? do_try_to_free_pages+0xe80/0xe80
[  905.904811]  __alloc_pages_slowpath+0x91d/0x26c0
[  905.909558]  ? bad_range+0xe7/0x3a0
[  905.913177]  ? warn_alloc+0xf0/0xf0
[  905.916783]  ? find_held_lock+0x2d/0x110
[  905.920834]  ? fs_reclaim_acquire+0x10/0x10
[  905.925133]  __alloc_pages_nodemask+0x5d3/0x700
[  905.929782]  ? rcu_read_lock_sched_held+0x10a/0x130
[  905.934775]  ? __alloc_pages_nodemask+0x5e0/0x700
[  905.939646]  ? __alloc_pages_slowpath+0x26c0/0x26c0
[  905.944643]  alloc_pages_current+0xe7/0x1e0
[  905.948944]  kvm_mmu_create+0xd1/0x1c0
[  905.952823]  kvm_arch_vcpu_init+0x28b/0x8b0
[  905.957141]  ? alloc_pages_current+0xef/0x1e0
[  905.961621]  kvm_vcpu_init+0x26d/0x360
[  905.965493]  vmx_create_vcpu+0xf3/0x2900
[  905.969600]  ? __mutex_unlock_slowpath+0x75/0x780
[  905.974424]  ? drop_futex_key_refs.isra.0+0x17/0x80
[  905.979438]  ? handle_rdmsr+0x6b0/0x6b0
[  905.983413]  kvm_vm_ioctl+0x49c/0x1430
[  905.987526]  ? __lock_acquire+0x5f7/0x4620
[  905.991795]  ? kvm_vcpu_release+0xa0/0xa0
[  905.995960]  ? trace_hardirqs_on+0x10/0x10
[  906.000239]  ? trace_hardirqs_on+0x10/0x10
[  906.004457]  ? save_trace+0x290/0x290
[  906.008237]  ? __might_fault+0x104/0x1b0
[  906.012429]  ? kvm_vcpu_release+0xa0/0xa0
[  906.016563]  do_vfs_ioctl+0x75a/0xfe0
[  906.020352]  ? selinux_file_mprotect+0x5c0/0x5c0
[  906.025115]  ? ioctl_preallocate+0x1a0/0x1a0
[  906.029504]  ? security_file_ioctl+0x76/0xb0
[  906.033890]  ? security_file_ioctl+0x83/0xb0
[  906.038276]  SyS_ioctl+0x7f/0xb0
[  906.041627]  ? do_vfs_ioctl+0xfe0/0xfe0
[  906.045589]  do_syscall_64+0x1d5/0x640
[  906.049457]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
[  906.054623] RIP: 0033:0x45c889
[  906.057793] RSP: 002b:00007f73f5256c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[  906.065477] RAX: ffffffffffffffda RBX: 00007f73f52576d4 RCX: 000000000045c889
[  906.072723] RDX: 0000000000000000 RSI: 000000000000ae41 RDI: 0000000000000006
[  906.079972] RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
[  906.087227] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
[  906.094482] R13: 0000000000000390 R14: 00000000004c60a9 R15: 000000000076bf0c
