INFO: task syz.4.753:7367 blocked for more than 148 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.753 state:D stack:27904 pid:7367 ppid:4273 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 io_schedule+0x7c/0xd0 kernel/sched/core.c:8797 folio_wait_bit_common+0x6e1/0xf60 mm/filemap.c:1324 folio_put_wait_locked mm/filemap.c:1493 [inline] do_read_cache_folio+0x1a9/0x760 mm/filemap.c:3609 erofs_bread+0x18e/0x670 fs/erofs/data.c:50 erofs_readdir+0x2a3/0xb20 fs/erofs/dir.c:65 iterate_dir+0x218/0x560 fs/readdir.c:-1 __do_sys_getdents fs/readdir.c:286 [inline] __se_sys_getdents+0xe5/0x250 fs/readdir.c:271 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f97a838f6c9 RSP: 002b:00007f97a65f6038 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f97a85e6090 RCX: 00007f97a838f6c9 RDX: cad9286a271020d7 RSI: 0000200000000400 RDI: 0000000000000006 RBP: 00007f97a8411f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f97a85e6128 R14: 00007f97a85e6090 R15: 00007ffcdafe12a8 Showing all locks held in the system: 3 locks held by kworker/u4:1/11: #0: ffff8880b8f3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffff8880b8f27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x398/0x6d0 kernel/sched/psi.c:999 #2: ffff8880b8f28418 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2b630 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4028: #0: ffff88802f4a7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 2 locks held by syz.4.753/7365: 2 locks held by syz.4.753/7367: #0: ffff88807dde7268 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x2ae/0x360 fs/file.c:1038 #1: ffff8880700d8198 (&type->i_mutex_dir_key#12){.+.+}-{3:3}, at: iterate_dir+0x10d/0x560 fs/readdir.c:55 2 locks held by syz.8.1044/8865: 1 lock held by sed/8899: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7365 Comm: syz.4.753 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:account_entity_enqueue kernel/sched/fair.c:3205 [inline] RIP: 0010:enqueue_entity+0x2eb/0x14f0 kernel/sched/fair.c:4775 Code: 48 8d 7d 78 48 89 f8 48 c1 e8 03 42 80 3c 38 00 74 05 e8 38 71 76 00 48 8b 7d 78 48 89 ee 4c 89 f2 e8 29 dd ff ff 4c 8b 24 24 <48> 89 e8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 ef e8 0f 71 76 00 RSP: 0018:ffffc900001e0b18 EFLAGS: 00000046 RAX: 1ffff1100f37b020 RBX: ffff888079bd8100 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef760 RBP: ffff888079bd8080 R08: dffffc0000000000 R09: fffffbfff1c3ed56 R10: fffffbfff1c3ed56 R11: 1ffffffff1c3ed55 R12: ffff8880b8f3ab80 R13: 0000000000000000 R14: ffff8880b8f3abd0 R15: dffffc0000000000 FS: 00007f97a91446c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0cba86de50 CR3: 0000000049a86000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: enqueue_task_fair+0x54b/0xaa0 kernel/sched/fair.c:6120 enqueue_task+0x182/0x2b0 kernel/sched/core.c:2059 activate_task kernel/sched/core.c:2087 [inline] ttwu_do_activate+0x1b7/0x320 kernel/sched/core.c:3699 ttwu_queue kernel/sched/core.c:3904 [inline] try_to_wake_up+0x5de/0x1080 kernel/sched/core.c:4227 hrtimer_wakeup+0x4a/0x60 kernel/time/hrtimer.c:1983 __run_hrtimer kernel/time/hrtimer.c:1747 [inline] __hrtimer_run_queues+0x554/0xd60 kernel/time/hrtimer.c:1811 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1948 [inline] RIP: 0010:vprintk_emit+0x461/0x680 kernel/printk/printk.c:2302 Code: 85 8f 01 00 00 e8 2f ba 1a 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 1e ba 1a 00 eb 06 e8 17 ba 1a 00 fb 48 c7 c7 40 ef b1 8c <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 37 db RSP: 0018:ffffc9000d937560 EFLAGS: 00000246 RAX: ffffffff81661c49 RBX: ffffffff81661af5 RCX: 0000000000080000 RDX: ffffc9000ceaa000 RSI: 000000000007ffff RDI: ffffffff8cb1ef40 RBP: ffffc9000d937650 R08: dffffc0000000000 R09: fffffbfff215c46e R10: fffffbfff215c46e R11: 1ffffffff215c46d R12: dffffc0000000000 R13: 1ffff92001b26eb0 R14: 0000000000000200 R15: 0000000000000056 _printk+0xcc/0x110 kernel/printk/printk.c:2328 _erofs_err+0x11f/0x170 fs/erofs/super.c:35 z_erofs_pcluster_readmore+0x367/0x4f0 fs/erofs/zdata.c:1658 z_erofs_read_folio+0x23b/0x5b0 fs/erofs/zdata.c:1681 filemap_read_folio+0x160/0x760 mm/filemap.c:2490 do_read_cache_folio+0x2a0/0x760 mm/filemap.c:3627 erofs_bread+0x18e/0x670 fs/erofs/data.c:50 erofs_readdir+0x2a3/0xb20 fs/erofs/dir.c:65 iterate_dir+0x218/0x560 fs/readdir.c:-1 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0xe5/0x260 fs/readdir.c:354 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f97a838f6c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f97a9144038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f97a85e5fa0 RCX: 00007f97a838f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007f97a8411f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f97a85e6038 R14: 00007f97a85e5fa0 R15: 00007ffcdafe12a8