INFO: task segctord:8891 blocked for more than 143 seconds. Not tainted 6.3.0-rc7-syzkaller-00189-g2caeeb9d4a1b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:segctord state:D stack:28696 pid:8891 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5307 [inline] __schedule+0x173b/0x4630 kernel/sched/core.c:6625 schedule+0xc3/0x180 kernel/sched/core.c:6701 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6760 rwsem_down_write_slowpath+0xedd/0x13a0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2508 [inline] nilfs_segctor_thread+0x52f/0x1140 fs/nilfs2/segment.c:2592 kthread+0x270/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cf25570 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cf25d70 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 1 lock held by khungtaskd/28: #0: ffffffff8cf253a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/4740: #0: ffff88814a456098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900015b02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ab/0x1db0 drivers/tty/n_tty.c:2177 1 lock held by syz-executor.2/5097: #0: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline] #0: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a3/0x890 kernel/rcu/tree_exp.h:989 2 locks held by kworker/1:22/8623: #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363 #1: ffffc90005267d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365 5 locks held by syz-executor.0/8877: 1 lock held by segctord/8891: #0: ffff888017bfe2a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357 2 locks held by syz-executor.3/20493: #0: ffff8880375a20e0 (&type->s_umount_key#66/1){+.+.}-{3:3}, at: alloc_super+0x217/0x930 fs/super.c:228 #1: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #1: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:989 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.3.0-rc7-syzkaller-00189-g2caeeb9d4a1b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x187/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xec2/0xf00 kernel/hung_task.c:379 kthread+0x270/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 20507 Comm: syz-executor.0 Not tainted 6.3.0-rc7-syzkaller-00189-g2caeeb9d4a1b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:check_preemption_disabled+0x2/0x110 lib/smp_processor_id.c:13 Code: ff ff ff 0f 1f 44 00 00 f3 0f 1e fa 48 c7 c7 a0 fe 37 8b 48 c7 c6 e0 fe 37 8b eb 0c 66 2e 0f 1f 84 00 00 00 00 00 66 90 41 57 <41> 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 RSP: 0000:ffffc9000600fe90 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8880284c9d40 RCX: 0000000000010000 RDX: 0000000000000001 RSI: ffffffff8b37fee0 RDI: ffffffff8b37fea0 RBP: ffffc9000600ff28 R08: dffffc0000000000 R09: fffffbfff1ca6956 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000c01fd4 R14: ffffc9000600fec0 R15: 0000000000000000 FS: 00007f8a94c2a700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8a8a7ea000 CR3: 0000000022854000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tick_irq_exit kernel/softirq.c:630 [inline] __irq_exit_rcu+0x15e/0x240 kernel/softirq.c:652 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x47/0xb0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0033:0x7f8a93e29231 Code: 45 10 48 39 c1 77 78 48 63 d5 48 01 c2 49 3b 55 08 77 56 8d 55 ff 85 ed 74 35 0f 1f 80 00 00 00 00 48 39 c1 77 1c 49 8b 75 00 <49> 89 c1 49 29 c9 46 0f b6 0c 0e 45 84 c9 74 08 44 88 0c 06 49 8b RSP: 002b:00007f8a94c29600 EFLAGS: 00000293 RAX: 00000000001eb087 RBX: 00007f8a94c29660 RCX: 0000000000000001 RDX: 00000000000000ba RSI: 00007f8a8a5ff000 RDI: 00007f8a94c29700 RBP: 0000000000000102 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 00007f8a94c29670 R12: 00007f8a94c29670 R13: 00007f8a94c29700 R14: 0000000000000001 R15: 0000000000000000