INFO: task syz.4.2360:15449 blocked for more than 143 seconds. Not tainted 6.11.0-rc4-syzkaller-00008-g6e4436539ae1 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.2360 state:D stack:27168 pid:15449 tgid:15449 ppid:13349 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 coredump_task_exit kernel/exit.c:434 [inline] do_exit+0x3fe/0x2bb0 kernel/exit.c:834 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fd/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f74fe179e79 RSP: 002b:00007ffcf3ff2948 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffdfc RBX: 0000000000198878 RCX: 00007f74fe179e79 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f74fe316064 RBP: 00007f74fe316064 R08: 00007f74fe315f80 R09: 00007ffcf3ff2c2f R10: 00007ffcf3ff2a40 R11: 0000000000000246 R12: 0000000000000032 R13: 00007ffcf3ff2a40 R14: 00007ffcf3ff2a60 R15: 0000000000198846 INFO: task syz.4.2360:15450 blocked for more than 144 seconds. Not tainted 6.11.0-rc4-syzkaller-00008-g6e4436539ae1 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.2360 state:D stack:29040 pid:15450 tgid:15449 ppid:13349 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 coredump_task_exit kernel/exit.c:434 [inline] do_exit+0x3fe/0x2bb0 kernel/exit.c:834 do_group_exit+0xd3/0x2a0 kernel/exit.c:1031 get_signal+0x25fd/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:310 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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f74fe179e79 RSP: 002b:00007f74fef2e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000007 RAX: fffffffffffffdfc RBX: 00007f74fe315f80 RCX: 00007f74fe179e79 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f74fe1e7916 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f74fe315f80 R15: 00007ffcf3ff27e8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8ddb5be0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8ddb5be0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8ddb5be0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 2 locks held by getty/4979: #0: ffff88802a2000a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900031232f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:6/5304: 2 locks held by kworker/0:6/5309: #0: ffff8880b923edd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:568 [inline] #0: ffff8880b923edd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:553 #1: ffff8880b9228a48 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2d9/0x900 kernel/sched/psi.c:989 2 locks held by syz-executor/13152: 2 locks held by syz-executor/13349: 2 locks held by syz-executor/13533: 1 lock held by syz-executor/13541: #0: ffffffff8ddc1378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:296 2 locks held by syz-executor/14769: 3 locks held by syz.4.2360/15452: 2 locks held by syz.0.2371/15470: 2 locks held by syz.3.2373/15471: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc4-syzkaller-00008-g6e4436539ae1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111