syzbot


riscv/fixes boot error: INFO: task hung in add_early_randomness

Status: fixed on 2023/02/24 13:50
Subsystems: crypto
[Documentation on labels]
Fix commit: 228432551bd8 virtio-rng: make device ready before making request
First crash: 666d, last: 616d

Sample crash report:
INFO: task swapper/0:1 blocked for more than 450 seconds.
      Not tainted 5.19.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:swapper/0       state:D stack:    0 pid:    1 ppid:     0 flags:0x00000000
Call Trace:
[<ffffffff83284868>] schedule+0x74/0x120 kernel/sched/core.c:6500
[<ffffffff83284fda>] schedule_preempt_disabled+0x16/0x28 kernel/sched/core.c:6559
[<ffffffff83287304>] __mutex_lock_common kernel/locking/mutex.c:679 [inline]
[<ffffffff83287304>] __mutex_lock+0x520/0xb3c kernel/locking/mutex.c:747
[<ffffffff83287934>] mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:799
[<ffffffff80e4f890>] add_early_randomness+0x2c/0x162 drivers/char/hw_random/core.c:69
[<ffffffff80e4fea2>] hwrng_register+0x2d0/0x380 drivers/char/hw_random/core.c:599
[<ffffffff80e5036e>] virtrng_scan+0x2c/0x6c drivers/char/hw_random/virtio-rng.c:205
[<ffffffff80d84cc2>] virtio_dev_probe+0x48e/0x742 drivers/virtio/virtio.c:313
[<ffffffff8144a9a8>] call_driver_probe drivers/base/dd.c:555 [inline]
[<ffffffff8144a9a8>] really_probe+0x194/0x7c0 drivers/base/dd.c:634
[<ffffffff8144b21e>] __driver_probe_device+0x24a/0x2d4 drivers/base/dd.c:764
[<ffffffff8144b308>] driver_probe_device+0x60/0x1a4 drivers/base/dd.c:794
[<ffffffff8144c2f6>] __driver_attach+0x178/0x368 drivers/base/dd.c:1163
[<ffffffff81445e0e>] bus_for_each_dev+0x122/0x194 drivers/base/bus.c:301
[<ffffffff81449bfa>] driver_attach+0x32/0x3c drivers/base/dd.c:1180
[<ffffffff814490c6>] bus_add_driver+0x2cc/0x432 drivers/base/bus.c:618
[<ffffffff8144d566>] driver_register+0x144/0x28a drivers/base/driver.c:240
[<ffffffff80d83ff8>] register_virtio_driver+0x5e/0x8c drivers/virtio/virtio.c:356
[<ffffffff83456128>] virtio_rng_driver_init+0x20/0x28 drivers/char/hw_random/virtio-rng.c:260
[<ffffffff80003274>] do_one_initcall+0x13c/0x7f0 init/main.c:1295
[<ffffffff83402062>] do_initcall_level init/main.c:1368 [inline]
[<ffffffff83402062>] do_initcalls init/main.c:1384 [inline]
[<ffffffff83402062>] do_basic_setup init/main.c:1403 [inline]
[<ffffffff83402062>] kernel_init_freeable+0x510/0x5b4 init/main.c:1610
[<ffffffff8328069e>] kernel_init+0x28/0x21c init/main.c:1499
[<ffffffff80005c08>] ret_from_exception+0x0/0x10

Showing all locks held in the system:
2 locks held by swapper/0/1:
 #0: ff6000000e6c7170 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:835 [inline]
 #0: ff6000000e6c7170 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1054 [inline]
 #0: ff6000000e6c7170 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x170/0x368 drivers/base/dd.c:1162
 #1: ffffffff85071828 (reading_mutex){+.+.}-{3:3}, at: add_early_randomness+0x2c/0x162 drivers/char/hw_random/core.c:69
1 lock held by khungtaskd/27:
 #0: ffffffff84d7a080 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x40/0x1e2 kernel/locking/lockdep.c:6493
2 locks held by kworker/u4:4/49:
 #0: ff60000007e29138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #0: ff60000007e29138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ff60000007e29138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x512/0xfc8 kernel/workqueue.c:2260
 #1: ff20000000577cf0 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #1: ff20000000577cf0 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #1: ff20000000577cf0 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0x512/0xfc8 kernel/workqueue.c:2260
1 lock held by hwrng/670:
 #0: ffffffff85071828 (reading_mutex){+.+.}-{3:3}, at: hwrng_fillfn+0xda/0x2a2 drivers/char/hw_random/core.c:503

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


Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/08/06 13:00 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes 88bd24d73d5b 88e3a122 .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
2022/07/26 09:23 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes 88bd24d73d5b 279b89c2 .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
2022/07/21 07:43 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes 89551fdd44a2 6e67af9d .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
2022/07/14 15:46 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes 7fccd7239127 5d921b08 .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
2022/07/13 07:34 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes dc5cb7a833e8 5d921b08 .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
2022/07/08 09:00 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes dc5cb7a833e8 8442e655 .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
2022/06/24 07:59 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes e83031564137 a5dbd430 .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
2022/06/16 23:22 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git fixes a7c1c97fb1e6 1719ee24 .config console log report ci-qemu2-riscv64 riscv/fixes boot error: INFO: task hung in add_early_randomness
* Struck through repros no longer work on HEAD.