INFO: task syz.5.2230:13830 blocked for more than 144 seconds. Not tainted 6.13.0-rc6-syzkaller-00046-g0b7958fa05d5 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.2230 state:D stack:23544 pid:13830 tgid:13829 ppid:6325 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 rwsem_down_read_slowpath kernel/locking/rwsem.c:1084 [inline] __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x705/0xa40 kernel/locking/rwsem.c:1526 __super_lock fs/super.c:58 [inline] super_lock+0x27c/0x400 fs/super.c:120 super_lock_shared fs/super.c:139 [inline] iterate_supers+0x8c/0x190 fs/super.c:931 ksys_sync+0xbd/0x1c0 fs/sync.c:102 __do_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc64ad85d29 RSP: 002b:00007fc64bba3038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fc64af75fa0 RCX: 00007fc64ad85d29 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fc64af75fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc64af75fa0 R15: 00007ffc21cee498 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 2 locks held by getty/5583: #0: ffff8880319bc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5817: #0: ffff88807e8180e0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807e8180e0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807e8180e0 (&type->s_umount_key#83){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 7 locks held by kworker/u8:29/9746: 1 lock held by syz.5.2230/13830: #0: ffff88807e8180e0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807e8180e0 (&type->s_umount_key#83){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.7.2456/14723: #0: ffff88807e8180e0 (&type->s_umount_key#83){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807e8180e0 (&type->s_umount_key#83){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120 1 lock held by syz.6.2732/15654: #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #0: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 2 locks held by dhcpcd/15687: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc6-syzkaller-00046-g0b7958fa05d5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111