kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 8580 Comm: udevd Not tainted 4.16.0+ #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:82
RSP: 0018:ffff8801db006888 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8801d2cbe278
RDX: 0000000000000007 RSI: ffffffff81783391 RDI: 0000000000000038
RBP: ffff8801db0068a0 R08: ffffed003b6046c3 R09: 0000000000000000
R10: ffff8801db006930 R11: ffff8801db023613 R12: ffff8801ae5ae1c0
R13: ffff8801d2cbe240 R14: ffff8801d2cbe27c R15: 0000000000000002
FS:  00007fd991dbd7a0(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000625208 CR3: 00000001ccd8a000 CR4: 00000000001406f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000020000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 delayacct_blkio_end include/linux/delayacct.h:128 [inline]
 try_to_wake_up+0xa89/0x1190 kernel/sched/core.c:2034
 default_wake_function+0x30/0x50 kernel/sched/core.c:3743
 autoremove_wake_function+0x7a/0x350 kernel/sched/wait.c:373
 wake_page_function+0x15f/0x1c0 mm/filemap.c:1010
 __wake_up_common+0x189/0x730 kernel/sched/wait.c:90
 __wake_up_locked_key_bookmark+0x16/0x20 kernel/sched/wait.c:165
 wake_up_page_bit+0x297/0x580 mm/filemap.c:1030
 wake_up_page mm/filemap.c:1071 [inline]
 end_page_writeback+0x24c/0x320 mm/filemap.c:1233
 ext4_finish_bio+0x593/0x940 fs/ext4/page-io.c:118
 ext4_end_bio+0x18f/0x6d0 fs/ext4/page-io.c:342
 bio_endio+0x4b8/0x920 block/bio.c:1775
 req_bio_endio block/blk-core.c:280 [inline]
 blk_update_request+0x3a3/0xcb0 block/blk-core.c:3076
 scsi_end_request+0xd3/0x870 drivers/scsi/scsi_lib.c:672
 scsi_io_completion+0xca9/0x1d10 drivers/scsi/scsi_lib.c:891
 scsi_finish_command+0x542/0x8d0 drivers/scsi/scsi.c:248
 scsi_softirq_done+0x3d9/0x4b0 drivers/scsi/scsi_lib.c:1676
 __blk_mq_complete_request+0x4c8/0x9f0 block/blk-mq.c:551
 blk_mq_complete_request+0x2a5/0x370 block/blk-mq.c:636
 scsi_mq_done+0xe2/0x430 drivers/scsi/scsi_lib.c:1987
 virtscsi_complete_cmd+0x573/0x740 drivers/scsi/virtio_scsi.c:207
 virtscsi_vq_done+0xc3/0x170 drivers/scsi/virtio_scsi.c:223
 virtscsi_req_done+0xa7/0xd0 drivers/scsi/virtio_scsi.c:238
 vring_interrupt+0x128/0x170 drivers/virtio/virtio_ring.c:950
 __handle_irq_event_percpu+0x1c0/0xad0 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x98/0x1c0 kernel/irq/handle.c:189
 handle_irq_event+0xa7/0x135 kernel/irq/handle.c:206
 handle_edge_irq+0x20f/0x870 kernel/irq/chip.c:791
 generic_handle_irq_desc include/linux/irqdesc.h:159 [inline]
 handle_irq+0x18c/0x2e7 arch/x86/kernel/irq_64.c:77
 do_IRQ+0x78/0x190 arch/x86/kernel/irq.c:245
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:641
 </IRQ>
RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:142 [inline]
RIP: 0010:PageAnon include/linux/page-flags.h:413 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1327 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1441 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1470 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1491 [inline]
RIP: 0010:unmap_page_range+0xb9c/0x2200 mm/memory.c:1512
RSP: 0018:ffff880194506e10 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffda
RAX: ffffea0006e8c420 RBX: ffff88017cb52e30 RCX: ffff880194507388
RDX: ffff880194507000 RSI: ffffffff81a4bc16 RDI: ffff8801945073a0
RBP: ffff8801945072a8 R08: ffff8801ae5ae1c0 R09: fffff94000dd1883
R10: fffff94000dd1883 R11: ffffea0006e8c41b R12: ffffea0006e8c680
R13: 0000000001dc7000 R14: dffffc0000000000 R15: ffff880194507000
 unmap_single_vma+0x1a0/0x310 mm/memory.c:1557
 unmap_vmas+0x120/0x1f0 mm/memory.c:1587
 exit_mmap+0x265/0x570 mm/mmap.c:3038
 __mmput kernel/fork.c:962 [inline]
 mmput+0x251/0x610 kernel/fork.c:983
 exec_mmap fs/exec.c:1044 [inline]
 flush_old_exec+0xb94/0x20e0 fs/exec.c:1276
 load_elf_binary+0xa33/0x5610 fs/binfmt_elf.c:869
 search_binary_handler+0x17d/0x570 fs/exec.c:1653
 exec_binprm fs/exec.c:1695 [inline]
 do_execveat_common.isra.34+0x16ce/0x2590 fs/exec.c:1817
 do_execve fs/exec.c:1862 [inline]
 SYSC_execve fs/exec.c:1943 [inline]
 SyS_execve+0x39/0x50 fs/exec.c:1938
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7fd9914a1207
RSP: 002b:00007ffc707db518 EFLAGS: 00000206 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fd9914a1207
RDX: 0000000001d5dad0 RSI: 00007ffc707db610 RDI: 00007ffc707dc620
RBP: 0000000000625500 R08: 000000000000686c R09: 000000000000686c
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000001d5dad0
R13: 0000000000000007 R14: 0000000001d4c250 R15: 0000000000000005
Code: fa 48 c1 ea 03 80 3c 02 00 0f 85 80 00 00 00 48 8b 9b 30 12 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 38 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 04 3c 03 7e 51 44 8b 63 38 31 ff 41 83 e4 
RIP: __delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:82 RSP: ffff8801db006888

======================================================
WARNING: possible circular locking dependency detected
4.16.0+ #4 Not tainted
------------------------------------------------------
udevd/8580 is trying to acquire lock:
000000006d943db4 ((console_sem).lock){-...}, at: down_trylock+0x13/0x70 kernel/locking/semaphore.c:136

but task is already holding lock:
00000000cec200d8 (&p->pi_lock){-.-.}, at: try_to_wake_up+0xca/0x1190 kernel/sched/core.c:1963

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #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/0x1190 kernel/sched/core.c:1963
       wake_up_process+0x10/0x20 kernel/sched/core.c:2126
       __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+0x7d6/0x1100 kernel/printk/printk.c:2417
       vprintk_emit+0x6ad/0xdd0 kernel/printk/printk.c:1907
       vprintk_default+0x28/0x30 kernel/printk/printk.c:1947
       vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:379
       printk+0x9e/0xba kernel/printk/printk.c:1980
       regdb_fw_cb.cold.35+0x18/0x89 net/wireless/reg.c:1074
       request_firmware_work_func+0x154/0x2c0 drivers/base/firmware_loader/main.c:749
       process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
       worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
       kthread+0x345/0x410 kernel/kthread.c:238
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:411

-> #0 ((console_sem).lock){-...}:
       lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920
       __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:2229
       console_trylock_spinning kernel/printk/printk.c:1643 [inline]
       vprintk_emit+0x694/0xdd0 kernel/printk/printk.c:1906
       vprintk_default+0x28/0x30 kernel/printk/printk.c:1947
       vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:379
       printk+0x9e/0xba kernel/printk/printk.c:1980
       kasan_die_handler.cold.22+0x11/0x30 arch/x86/mm/kasan_init_64.c:253
       notifier_call_chain+0x178/0x380 kernel/notifier.c:93
       __atomic_notifier_call_chain kernel/notifier.c:183 [inline]
       atomic_notifier_call_chain+0x98/0x190 kernel/notifier.c:193
       notify_die+0x1a3/0x2b0 kernel/notifier.c:549
       do_general_protection+0x248/0x2f0 arch/x86/kernel/traps.c:558
       general_protection+0x25/0x50 arch/x86/entry/entry_64.S:1158
       __delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:82
       delayacct_blkio_end include/linux/delayacct.h:128 [inline]
       try_to_wake_up+0xa89/0x1190 kernel/sched/core.c:2034
       default_wake_function+0x30/0x50 kernel/sched/core.c:3743
       autoremove_wake_function+0x7a/0x350 kernel/sched/wait.c:373
       wake_page_function+0x15f/0x1c0 mm/filemap.c:1010
       __wake_up_common+0x189/0x730 kernel/sched/wait.c:90
       __wake_up_locked_key_bookmark+0x16/0x20 kernel/sched/wait.c:165
       wake_up_page_bit+0x297/0x580 mm/filemap.c:1030
       wake_up_page mm/filemap.c:1071 [inline]
       end_page_writeback+0x24c/0x320 mm/filemap.c:1233
       ext4_finish_bio+0x593/0x940 fs/ext4/page-io.c:118
       ext4_end_bio+0x18f/0x6d0 fs/ext4/page-io.c:342
       bio_endio+0x4b8/0x920 block/bio.c:1775
       req_bio_endio block/blk-core.c:280 [inline]
       blk_update_request+0x3a3/0xcb0 block/blk-core.c:3076
       scsi_end_request+0xd3/0x870 drivers/scsi/scsi_lib.c:672
       scsi_io_completion+0xca9/0x1d10 drivers/scsi/scsi_lib.c:891
       scsi_finish_command+0x542/0x8d0 drivers/scsi/scsi.c:248
       scsi_softirq_done+0x3d9/0x4b0 drivers/scsi/scsi_lib.c:1676
       __blk_mq_complete_request+0x4c8/0x9f0 block/blk-mq.c:551
       blk_mq_complete_request+0x2a5/0x370 block/blk-mq.c:636
       scsi_mq_done+0xe2/0x430 drivers/scsi/scsi_lib.c:1987
       virtscsi_complete_cmd+0x573/0x740 drivers/scsi/virtio_scsi.c:207
       virtscsi_vq_done+0xc3/0x170 drivers/scsi/virtio_scsi.c:223
       virtscsi_req_done+0xa7/0xd0 drivers/scsi/virtio_scsi.c:238
       vring_interrupt+0x128/0x170 drivers/virtio/virtio_ring.c:950
       __handle_irq_event_percpu+0x1c0/0xad0 kernel/irq/handle.c:149
       handle_irq_event_percpu+0x98/0x1c0 kernel/irq/handle.c:189
       handle_irq_event+0xa7/0x135 kernel/irq/handle.c:206
       handle_edge_irq+0x20f/0x870 kernel/irq/chip.c:791
       generic_handle_irq_desc include/linux/irqdesc.h:159 [inline]
       handle_irq+0x18c/0x2e7 arch/x86/kernel/irq_64.c:77
       do_IRQ+0x78/0x190 arch/x86/kernel/irq.c:245
       ret_from_intr+0x0/0x1e
       __read_once_size include/linux/compiler.h:188 [inline]
       compound_head include/linux/page-flags.h:142 [inline]
       PageAnon include/linux/page-flags.h:413 [inline]
       zap_pte_range mm/memory.c:1327 [inline]
       zap_pmd_range mm/memory.c:1441 [inline]
       zap_pud_range mm/memory.c:1470 [inline]
       zap_p4d_range mm/memory.c:1491 [inline]
       unmap_page_range+0xb9c/0x2200 mm/memory.c:1512
       unmap_single_vma+0x1a0/0x310 mm/memory.c:1557
       unmap_vmas+0x120/0x1f0 mm/memory.c:1587
       exit_mmap+0x265/0x570 mm/mmap.c:3038
       __mmput kernel/fork.c:962 [inline]
       mmput+0x251/0x610 kernel/fork.c:983
       exec_mmap fs/exec.c:1044 [inline]
       flush_old_exec+0xb94/0x20e0 fs/exec.c:1276
       load_elf_binary+0xa33/0x5610 fs/binfmt_elf.c:869
       search_binary_handler+0x17d/0x570 fs/exec.c:1653
       exec_binprm fs/exec.c:1695 [inline]
       do_execveat_common.isra.34+0x16ce/0x2590 fs/exec.c:1817
       do_execve fs/exec.c:1862 [inline]
       SYSC_execve fs/exec.c:1943 [inline]
       SyS_execve+0x39/0x50 fs/exec.c:1938
       do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&p->pi_lock);
                               lock((console_sem).lock);
                               lock(&p->pi_lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

7 locks held by udevd/8580:
 #0: 0000000091d409f7 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x53/0x120 fs/exec.c:1404
 #1: 00000000f4acfcde (&(ptlock_ptr(page))->rlock#2){+.+.}, at: spin_lock include/linux/spinlock.h:310 [inline]
 #1: 00000000f4acfcde (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_pte_range mm/memory.c:1298 [inline]
 #1: 00000000f4acfcde (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_pmd_range mm/memory.c:1441 [inline]
 #1: 00000000f4acfcde (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_pud_range mm/memory.c:1470 [inline]
 #1: 00000000f4acfcde (&(ptlock_ptr(page))->rlock#2){+.+.}, at: zap_p4d_range mm/memory.c:1491 [inline]
 #1: 00000000f4acfcde (&(ptlock_ptr(page))->rlock#2){+.+.}, at: unmap_page_range+0x99b/0x2200 mm/memory.c:1512
 #2: 000000001f6ebf80 (&(&virtscsi_vq->vq_lock)->rlock){-.-.}, at: virtscsi_vq_done+0x9d/0x170 drivers/scsi/virtio_scsi.c:219
 #3: 000000003f9ab6df (rcu_read_lock){....}, at: hctx_lock+0x7a/0x1d0 block/blk-mq.c:570
 #4: 00000000ee62e23b (&page_wait_table[i]){-.-.}, at: wake_up_page_bit+0x27d/0x580 mm/filemap.c:1029
 #5: 00000000cec200d8 (&p->pi_lock){-.-.}, at: try_to_wake_up+0xca/0x1190 kernel/sched/core.c:1963
 #6: 000000003f9ab6df (rcu_read_lock){....}, at: atomic_notifier_call_chain+0x0/0x190 include/linux/compiler.h:188

stack backtrace:
CPU: 0 PID: 8580 Comm: udevd Not tainted 4.16.0+ #4
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.54+0x1bd/0x27d kernel/locking/lockdep.c:1223
 check_prev_add kernel/locking/lockdep.c:1863 [inline]
 check_prevs_add kernel/locking/lockdep.c:1976 [inline]
 validate_chain kernel/locking/lockdep.c:2417 [inline]
 __lock_acquire+0x343e/0x5140 kernel/locking/lockdep.c:3431
 lock_acquire+0x1dc/0x520 kernel/locking/lockdep.c:3920
 __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:2229
 console_trylock_spinning kernel/printk/printk.c:1643 [inline]
 vprintk_emit+0x694/0xdd0 kernel/printk/printk.c:1906
 vprintk_default+0x28/0x30 kernel/printk/printk.c:1947
 vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:379
 printk+0x9e/0xba kernel/printk/printk.c:1980
 kasan_die_handler.cold.22+0x11/0x30 arch/x86/mm/kasan_init_64.c:253
 notifier_call_chain+0x178/0x380 kernel/notifier.c:93
 __atomic_notifier_call_chain kernel/notifier.c:183 [inline]
 atomic_notifier_call_chain+0x98/0x190 kernel/notifier.c:193
 notify_die+0x1a3/0x2b0 kernel/notifier.c:549
 do_general_protection+0x248/0x2f0 arch/x86/kernel/traps.c:558
 general_protection+0x25/0x50 arch/x86/entry/entry_64.S:1158
RIP: 0010:__delayacct_blkio_end+0x4f/0xc0 kernel/delayacct.c:82
RSP: 0018:ffff8801db006888 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8801d2cbe278
RDX: 0000000000000007 RSI: ffffffff81783391 RDI: 0000000000000038
RBP: ffff8801db0068a0 R08: ffffed003b6046c3 R09: 0000000000000000
R10: ffff8801db006930 R11: ffff8801db023613 R12: ffff8801ae5ae1c0
R13: ffff8801d2cbe240 R14: ffff8801d2cbe27c R15: 0000000000000002
 delayacct_blkio_end include/linux/delayacct.h:128 [inline]
 try_to_wake_up+0xa89/0x1190 kernel/sched/core.c:2034
 default_wake_function+0x30/0x50 kernel/sched/core.c:3743
 autoremove_wake_function+0x7a/0x350 kernel/sched/wait.c:373
 wake_page_function+0x15f/0x1c0 mm/filemap.c:1010
 __wake_up_common+0x189/0x730 kernel/sched/wait.c:90
 __wake_up_locked_key_bookmark+0x16/0x20 kernel/sched/wait.c:165
 wake_up_page_bit+0x297/0x580 mm/filemap.c:1030
 wake_up_page mm/filemap.c:1071 [inline]
 end_page_writeback+0x24c/0x320 mm/filemap.c:1233
 ? ext4_release_
Lost 180 message(s)!
---[ end trace bcaa80360a7c740d ]---