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INFO: task hung in scsi_host_dev_release (2)

Status: premoderation: reported on 2026/01/31 15:39
Reported-by: syzbot+275d44ad149cce9dd0dc@syzkaller.appspotmail.com
First crash: 1d01h, last: 1d01h
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in scsi_host_dev_release (3) kernel 1 3 129d 154d 0/29 auto-obsoleted due to no activity on 2025/12/24 11:04
upstream INFO: task hung in scsi_host_dev_release scsi 1 1 449d 449d 0/29 auto-obsoleted due to no activity on 2025/02/06 21:36
upstream INFO: task hung in scsi_host_dev_release (2) kernel 1 1 324d 324d 0/29 auto-obsoleted due to no activity on 2025/06/11 22:31
android-6-12 INFO: task hung in scsi_host_dev_release 1 2 150d 209d 0/1 auto-obsoleted due to no activity on 2025/12/02 22:05

Sample crash report:
INFO: task kworker/1:0:31 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:0     state:D stack:0     pid:31    tgid:31    ppid:2      flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5996 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
 __schedule_loop kernel/sched/core.c:7924 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7939
 schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common+0x369/0x650 kernel/sched/completion.c:127
 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
 rcu_barrier+0x415/0x540 kernel/rcu/tree.c:4657
 scsi_host_dev_release+0xae/0x2f0 drivers/scsi/hosts.c:344
 device_release+0xae/0x1e0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1aa/0x2a0 lib/kobject.c:737
 put_device+0x23/0x40 drivers/base/core.c:3800
 scsi_host_put+0x20/0x30 drivers/scsi/hosts.c:626
 release_everything+0x1f8/0x210 drivers/usb/storage/usb.c:971
 usb_stor_disconnect+0x1b9/0x1f0 drivers/usb/storage/usb.c:1179
 usb_unbind_interface+0x2aa/0xa30 drivers/usb/core/driver.c:462
 device_remove drivers/base/dd.c:569 [inline]
 __device_release_driver drivers/base/dd.c:1272 [inline]
 device_release_driver_internal+0x4c5/0x790 drivers/base/dd.c:1295
 device_release_driver+0x1d/0x30 drivers/base/dd.c:1318
 bus_remove_device+0x359/0x380 drivers/base/bus.c:576
 device_del+0x581/0xd00 drivers/base/core.c:3881
 usb_disable_device+0x3af/0x770 drivers/usb/core/message.c:1418
 usb_disconnect+0x322/0x930 drivers/usb/core/hub.c:2353
 hub_port_connect drivers/usb/core/hub.c:5414 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5714 [inline]
 port_event drivers/usb/core/hub.c:5878 [inline]
 hub_event+0x1c7a/0x4700 drivers/usb/core/hub.c:5960
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
 kthread+0x2c9/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task syz.3.149:818 blocked for more than 123 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.149       state:D stack:0     pid:818   tgid:818   ppid:291    flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5996 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
 __schedule_loop kernel/sched/core.c:7924 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7939
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589
 kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572
 kvm_arch_destroy_vm+0x398/0x420 arch/x86/kvm/x86.c:12961
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
 __fput+0x1fe/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e5/0x260 kernel/task_work.c:246
 resume_user_mode_work+0x35/0x50 include/linux/resume_user_mode.h:50
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x63/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f47dcd9aeb9
RSP: 002b:00007ffd9446b3a8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffd9446b490 RCX: 00007f47dcd9aeb9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 000000000000a779 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2e020000 R11: 0000000000000246 R12: 00007ffd9446b4d0
R13: 00007f47dd01618c R14: 000000000000a8df R15: 00007f47dd016180
 </TASK>
INFO: task syz.1.150:821 blocked for more than 124 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.150       state:D stack:0     pid:821   tgid:821   ppid:289    flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5996 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
 __schedule_loop kernel/sched/core.c:7924 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7939
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589
 kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572
 kvm_arch_destroy_vm+0x398/0x420 arch/x86/kvm/x86.c:12961
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
 __fput+0x1fe/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e5/0x260 kernel/task_work.c:246
 resume_user_mode_work+0x35/0x50 include/linux/resume_user_mode.h:50
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x63/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f264af9aeb9
RSP: 002b:00007ffed98679c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f264b217da0 RCX: 00007f264af9aeb9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f264b217da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007f264b217cb0 R11: 0000000000000246 R12: 000000000000aafe
R13: 00007f264b21609c R14: 000000000000a92f R15: 00007f264b216090
 </TASK>
INFO: task syz.0.151:836 blocked for more than 127 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.151       state:D stack:0     pid:836   tgid:835   ppid:290    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5996 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
 __schedule_loop kernel/sched/core.c:7924 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7939
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589
 kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572
 kvm_arch_destroy_vm+0x398/0x420 arch/x86/kvm/x86.c:12961
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
 __fput+0x1fe/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e5/0x260 kernel/task_work.c:246
 get_signal+0x1302/0x14e0 kernel/signal.c:2706
 arch_do_signal_or_restart+0xbc/0x760 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f7aa979ab4b
RSP: 002b:00007f7aaa573450 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000200000fe8000 RCX: 00007f7aa979ab4b
RDX: 00007f7aaa573bd0 RSI: 000000004020ae46 RDI: 0000000000000005
RBP: 0000000000000005 R08: 0000000000000001 R09: 0000000000000017
R10: 0000000000000005 R11: 0000000000000246 R12: 00000000fec00000
R13: 00007f7aaa573bd0 R14: 0000200000fe9000 R15: 0000000000000001
 </TASK>
INFO: task syz.0.151:840 blocked for more than 129 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.151       state:D stack:0     pid:840   tgid:835   ppid:290    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5996 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7843
 __schedule_loop kernel/sched/core.c:7924 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7939
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7996
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rcu_barrier+0x4d/0x540 kernel/rcu/tree.c:4589
 kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572
 kvm_arch_destroy_vm+0x398/0x420 arch/x86/kvm/x86.c:12961
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
 __fput+0x1fe/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e5/0x260 kernel/task_work.c:246
 get_signal+0x1302/0x14e0 kernel/signal.c:2706
 arch_do_signal_or_restart+0xbc/0x760 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f7aa979ab4b
RSP: 002b:00007f7aa7db1450 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffea RBX: 0000200000fe8000 RCX: 00007f7aa979ab4b
RDX: 00007f7aa7db1bd0 RSI: 000000004020ae46 RDI: 000000000000000a
RBP: 000000000000000a R08: 0000000000000001 R09: 0000000000000048
R10: 000000000000000a R11: 0000000000000246 R12: 00000000fec00000
R13: 00007f7aa7db1bd0 R14: 0000200000fe9000 R15: 0000000000000001
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 001c7e68fa735976e9f6b7ad125989e1d2b10b0e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xdad/0xf00 kernel/hung_task.c:423
 kthread+0x2c9/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 20 Comm: rcuop/0 Not tainted syzkaller #0 001c7e68fa735976e9f6b7ad125989e1d2b10b0e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__sanitizer_cov_trace_const_cmp2+0x8/0x90 kernel/kcov.c:308
Code: 74 11 18 48 89 44 11 20 5d e9 84 6f 19 04 cc 0f 1f 00 b8 9e 1c 13 e1 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 <48> 8b 45 08 65 48 8b 15 7c 4a 7d 7e 65 8b 0d 7d 4a 7d 7e 81 e1 00
RSP: 0018:ffffc90000230390 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8881512c9d36 RCX: ffff888103663900
RDX: 0000000000000100 RSI: 0000000000000038 RDI: 000000000000ffff
RBP: ffffc90000230390 R08: 0000000000000001 R09: 1ffff1102087165a
R10: dffffc0000000000 R11: ffffed102087165b R12: 1ffff1102a2593a6
R13: dffffc0000000000 R14: ffff8881512c9c80 R15: 0000000000000038
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe34074bdc CR3: 000000010c354000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 skb_transport_header_was_set include/linux/skbuff.h:2989 [inline]
 __netif_receive_skb_core+0x1e8/0x3ab0 net/core/dev.c:5564
 __netif_receive_skb_one_core net/core/dev.c:5761 [inline]
 __netif_receive_skb net/core/dev.c:5876 [inline]
 netif_receive_skb_internal net/core/dev.c:5962 [inline]
 netif_receive_skb+0xe0/0x7b0 net/core/dev.c:6021
 br_netif_receive_skb net/bridge/br_input.c:30 [inline]
 NF_HOOK include/linux/netfilter.h:317 [inline]
 br_pass_frame_up+0x126/0x1b0 net/bridge/br_input.c:70
 br_handle_frame_finish+0x1317/0x1760 net/bridge/br_input.c:221
 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
 br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424
 __netif_receive_skb_core+0xfae/0x3ab0 net/core/dev.c:5657
 __netif_receive_skb_one_core net/core/dev.c:5761 [inline]
 __netif_receive_skb net/core/dev.c:5876 [inline]
 process_backlog+0x3e5/0xad0 net/core/dev.c:6212
 __napi_poll+0xd3/0x610 net/core/dev.c:6863
 napi_poll net/core/dev.c:6932 [inline]
 net_rx_action+0x5ea/0xd80 net/core/dev.c:7054
 handle_softirqs+0x1aa/0x630 kernel/softirq.c:621
 __do_softirq+0xf/0x16 kernel/softirq.c:659
 do_softirq+0xb8/0x110 kernel/softirq.c:503
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594
 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
 rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957
 kthread+0x2c9/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/31 15:38 android16-6.12 c13babfee861 afc0c4d4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in scsi_host_dev_release
* Struck through repros no longer work on HEAD.