INFO: task syz.5.642:6296 blocked for more than 430 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.642 state:D stack:0 pid:6296 tgid:6296 ppid:4570 task_flags:0x400040 flags:0x00000019 Call trace: __switch_to+0x584/0xb20 arch/arm64/kernel/process.c:741 (T) context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1eec/0x33a4 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xac/0x27c kernel/sched/core.c:7026 schedule_timeout+0x5c/0x1e4 kernel/time/sleep_timeout.c:75 do_wait_for_common+0x28c/0x444 kernel/sched/completion.c:100 __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x44/0x5c kernel/sched/completion.c:153 __synchronize_srcu+0x2a4/0x320 kernel/rcu/srcutree.c:1454 synchronize_srcu+0x3cc/0x4f0 kernel/rcu/srcutree.c:-1 mmu_notifier_unregister+0x320/0x42c mm/mmu_notifier.c:831 kvm_destroy_vm virt/kvm/kvm_main.c:1295 [inline] kvm_put_kvm+0x698/0xbe8 virt/kvm/kvm_main.c:1353 kvm_vm_release+0x58/0x78 virt/kvm/kvm_main.c:1376 __fput+0x4ac/0x980 fs/file_table.c:468 ____fput+0x20/0x58 fs/file_table.c:496 task_work_run+0x1bc/0x254 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xfc/0x178 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:103 [inline] el0_svc+0x170/0x234 arch/arm64/kernel/entry-common.c:747 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffff800087957348 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330 1 lock held by udevd/3141: 2 locks held by getty/3195: #0: 2df00000120368a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ceff80008c6db2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x310/0x12b8 drivers/tty/n_tty.c:2222 1 lock held by sshd-session/3319: 2 locks held by syz-executor/3320: 3 locks held by kworker/u4:1/3369: 3 locks held by kworker/u4:2/5554: 3 locks held by kworker/u4:10/5761: 3 locks held by kworker/u4:9/6285: 2 locks held by syz.4.640/6290: 1 lock held by syz-executor/6300: 3 locks held by syz-executor/6308: 3 locks held by kworker/u4:12/6373: 3 locks held by kworker/u4:13/6393: 2 locks held by kworker/u4:14/6462: 2 locks held by syz.6.643/6470: 4 locks held by dhcpcd-run-hook/6474: ============================================= INFO: task syz.5.642:6296 blocked for more than 451 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.642 state:D stack:0 pid:6296 tgid:6296 ppid:4570 task_flags:0x400040 flags:0x00000019 Call trace: __switch_to+0x584/0xb20 arch/arm64/kernel/process.c:741 (T) context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1eec/0x33a4 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xac/0x27c kernel/sched/core.c:7026 schedule_timeout+0x5c/0x1e4 kernel/time/sleep_timeout.c:75 do_wait_for_common+0x28c/0x444 kernel/sched/completion.c:100 __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x44/0x5c kernel/sched/completion.c:153 __synchronize_srcu+0x2a4/0x320 kernel/rcu/srcutree.c:1454 synchronize_srcu+0x3cc/0x4f0 kernel/rcu/srcutree.c:-1 mmu_notifier_unregister+0x320/0x42c mm/mmu_notifier.c:831 kvm_destroy_vm virt/kvm/kvm_main.c:1295 [inline] kvm_put_kvm+0x698/0xbe8 virt/kvm/kvm_main.c:1353 kvm_vm_release+0x58/0x78 virt/kvm/kvm_main.c:1376 __fput+0x4ac/0x980 fs/file_table.c:468 ____fput+0x20/0x58 fs/file_table.c:496 task_work_run+0x1bc/0x254 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xfc/0x178 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:103 [inline] el0_svc+0x170/0x234 arch/arm64/kernel/entry-common.c:747 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffff800087957348 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330 1 lock held by klogd/3130: 2 locks held by getty/3195: #0: 2df00000120368a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ceff80008c6db2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x310/0x12b8 drivers/tty/n_tty.c:2222 3 locks held by kworker/u4:1/3369: 2 locks held by kworker/u4:3/3377: 3 locks held by kworker/u4:7/4268: 2 locks held by syz.4.640/6290: 3 locks held by kworker/u4:14/6462: 2 locks held by kworker/0:7/6464: 2 locks held by syz.6.643/6470: =============================================