syzbot


INFO: task hung in add_early_randomness

Status: closed as invalid on 2022/02/08 09:50
Subsystems: crypto
[Documentation on labels]
First crash: 848d, last: 848d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in add_early_randomness (2) usb crypto C done 182 471d 690d 22/26 fixed on 2023/02/24 13:50
linux-5.15 INFO: task hung in add_early_randomness 20 277d 402d 0/3 auto-obsoleted due to no activity on 2023/10/20 14:04
upstream INFO: task hung in add_early_randomness (3) crypto 7 334d 392d 0/26 auto-obsoleted due to no activity on 2023/08/22 21:25

Sample crash report:
INFO: task kworker/0:1:8233 blocked for more than 143 seconds.
      Not tainted 5.16.0-rc6-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:1     state:D stack:23456 pid: 8233 ppid:     2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6385
 __mutex_lock_common kernel/locking/mutex.c:680 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740
 add_early_randomness+0x1a/0x170 drivers/char/hw_random/core.c:69
 hwrng_register+0x44e/0x600 drivers/char/hw_random/core.c:517
 chaoskey_probe+0x7b5/0xc40 drivers/usb/misc/chaoskey.c:205
 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:517 [inline]
 really_probe+0x245/0xcc0 drivers/base/dd.c:596
 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
 __device_attach+0x228/0x4a0 drivers/base/dd.c:969
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
 device_add+0xc17/0x1ee0 drivers/base/core.c:3394
 usb_set_configuration+0x101e/0x1900 drivers/usb/core/message.c:2170
 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238
 usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:517 [inline]
 really_probe+0x245/0xcc0 drivers/base/dd.c:596
 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
 __device_attach+0x228/0x4a0 drivers/base/dd.c:969
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
 device_add+0xc17/0x1ee0 drivers/base/core.c:3394
 usb_new_device.cold+0x63f/0x108e drivers/usb/core/hub.c:2563
 hub_port_connect drivers/usb/core/hub.c:5353 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5497 [inline]
 port_event drivers/usb/core/hub.c:5643 [inline]
 hub_event+0x23e5/0x4460 drivers/usb/core/hub.c:5725
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb83e20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
1 lock held by hwrng/755:
 #0: ffffffff8c5ea588 (reading_mutex){+.+.}-{3:3}, at: hwrng_fillfn+0x132/0x2d0 drivers/char/hw_random/core.c:435
3 locks held by kworker/u4:4/976:
2 locks held by getty/3281:
 #0: ffff88814aed4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002b962e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113
1 lock held by syz-executor.3/3630:
 #0: ffff88801a6f5918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xc70 block/bdev.c:817
2 locks held by kworker/u4:10/9633:
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
 #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2269
 #1: ffffc9000d487db0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2273
3 locks held by syz-executor.5/12640:
6 locks held by kworker/0:1/8233:
 #0: ffff888141fe8938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888141fe8938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888141fe8938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888141fe8938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #0: ffff888141fe8938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
 #0: ffff888141fe8938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2269
 #1: ffffc9000f07fdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2273
 #2: ffff88801d4d6220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff88801d4d6220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4460 drivers/usb/core/hub.c:5671
 #3: ffff88807d900220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #3: ffff88807d900220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
 #4: ffff88802baed1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #4: ffff88802baed1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
 #5: ffffffff8c5ea588 (reading_mutex){+.+.}-{3:3}, at: add_early_randomness+0x1a/0x170 drivers/char/hw_random/core.c:69
3 locks held by udevd/27381:
 #0: ffff88802297c888 (&of->mutex){+.+.}-{3:3}, at: kernfs_file_read_iter fs/kernfs/file.c:203 [inline]
 #0: ffff88802297c888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_read_iter+0x185/0x5f0 fs/kernfs/file.c:242
 #1: ffff88802ac42da0 (kn->active#56){++++}-{0:0}, at: kernfs_file_read_iter fs/kernfs/file.c:204 [inline]
 #1: ffff88802ac42da0 (kn->active#56){++++}-{0:0}, at: kernfs_fop_read_iter+0x1a8/0x5f0 fs/kernfs/file.c:242
 #2: ffff88807d900220 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:765 [inline]
 #2: ffff88807d900220 (&dev->mutex){....}-{3:3}, at: read_descriptors+0x3c/0x2c0 drivers/usb/core/sysfs.c:873
2 locks held by udevd/748:
 #0: ffff88801a6f5918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x99/0x980 block/bdev.c:915
 #1: ffff88801a6f1360 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x7a/0x1070 drivers/block/loop.c:1106
1 lock held by syz-executor.0/32618:
5 locks held by syz-executor.1/32620:

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:295
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 32611 Comm: syz-executor.2 Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rcu_read_lock_held_common kernel/rcu/update.c:108 [inline]
RIP: 0010:rcu_read_lock_sched_held+0x1c/0x70 kernel/rcu/update.c:123
Code: c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 54 41 bc 01 00 00 00 e8 e3 ec e2 07 85 c0 75 06 44 89 e0 41 5c c3 e8 44 7c 00 00 <84> c0 74 41 e8 1b 9d 00 00 84 c0 74 38 be ff ff ff ff 48 c7 c7 60
RSP: 0018:ffffc90005ed7600 EFLAGS: 00000282
RAX: 0000000000000001 RBX: 1ffff92000bdaec4 RCX: ffffffff815cbad8
RDX: 0000000000000000 RSI: 0000000000000003 RDI: ffffffff8b5648a8
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8d915557
R10: fffffbfff1b22aaa R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: ffffffff8bb83e20 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb284e62058 CR3: 000000000b88e000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5608
 rcu_lock_acquire include/linux/rcupdate.h:268 [inline]
 rcu_read_lock include/linux/rcupdate.h:688 [inline]
 folio_memcg_lock+0x3a/0x3e0 mm/memcontrol.c:2010
 page_remove_rmap+0x25/0x1480 mm/rmap.c:1348
 zap_pte_range mm/memory.c:1357 [inline]
 zap_pmd_range mm/memory.c:1467 [inline]
 zap_pud_range mm/memory.c:1496 [inline]
 zap_p4d_range mm/memory.c:1517 [inline]
 unmap_page_range+0xf0e/0x29f0 mm/memory.c:1538
 unmap_single_vma+0x198/0x310 mm/memory.c:1583
 unmap_vmas+0x16b/0x2f0 mm/memory.c:1615
 exit_mmap+0x1d0/0x630 mm/mmap.c:3170
 __mmput+0x122/0x4b0 kernel/fork.c:1113
 mmput+0x56/0x60 kernel/fork.c:1134
 exit_mm kernel/exit.c:507 [inline]
 do_exit+0xb27/0x2b40 kernel/exit.c:819
 do_group_exit+0x125/0x310 kernel/exit.c:929
 get_signal+0x47d/0x2220 kernel/signal.c:2852
 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9124fe9e99
Code: Unable to access opcode bytes at RIP 0x7f9124fe9e6f.
RSP: 002b:00007f91238db218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f91250fd2a8 RCX: 00007f9124fe9e99
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f91250fd2a8
RBP: 00007f91250fd2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f91250fd2ac
R13: 00007ffd8bf087df R14: 00007f91238db300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess):
   0:	c3                   	retq
   1:	66 66 2e 0f 1f 84 00 	data16 nopw %cs:0x0(%rax,%rax,1)
   8:	00 00 00 00
   c:	66 90                	xchg   %ax,%ax
   e:	41 54                	push   %r12
  10:	41 bc 01 00 00 00    	mov    $0x1,%r12d
  16:	e8 e3 ec e2 07       	callq  0x7e2ecfe
  1b:	85 c0                	test   %eax,%eax
  1d:	75 06                	jne    0x25
  1f:	44 89 e0             	mov    %r12d,%eax
  22:	41 5c                	pop    %r12
  24:	c3                   	retq
  25:	e8 44 7c 00 00       	callq  0x7c6e
* 2a:	84 c0                	test   %al,%al <-- trapping instruction
  2c:	74 41                	je     0x6f
  2e:	e8 1b 9d 00 00       	callq  0x9d4e
  33:	84 c0                	test   %al,%al
  35:	74 38                	je     0x6f
  37:	be ff ff ff ff       	mov    $0xffffffff,%esi
  3c:	48                   	rex.W
  3d:	c7                   	.byte 0xc7
  3e:	c7                   	(bad)
  3f:	60                   	(bad)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/26 23:15 upstream 438645193e59 e4f103c4 .config console log report info ci-upstream-kasan-gce-root INFO: task hung in add_early_randomness
* Struck through repros no longer work on HEAD.