INFO: task segctord:11536 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. segctord D30088 11536 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x4f/0x90 kernel/locking/rwsem.c:72 nilfs_transaction_lock+0x1fb/0x8b0 fs/nilfs2/segment.c:362 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2479 [inline] nilfs_segctor_thread+0x3c0/0xf50 fs/nilfs2/segment.c:2563 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 00000000e39f30e5 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7864: #0: 000000000614e4e9 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by agetty/8065: #0: 00000000e74cb4ee (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000c678d68a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1950 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.5/8178: 7 locks held by syz-executor.1/11531: 1 lock held by segctord/11536: #0: 00000000631fbcf6 (&nilfs->ns_segctor_sem){++++}, at: nilfs_transaction_lock+0x1fb/0x8b0 fs/nilfs2/segment.c:362 2 locks held by kworker/u4:10/15882: 2 locks held by syz-executor.3/18644: #0: 0000000081f15290 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #0: 0000000081f15290 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:598 #1: 00000000ac3f12fa (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #1: 00000000ac3f12fa (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x4dc/0x6f0 kernel/rcu/tree_exp.h:667 2 locks held by syz-executor.4/18650: #0: 000000007d5562ec (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000007d5562ec (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 #1: 00000000ac3f12fa (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #1: 00000000ac3f12fa (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x256/0x6f0 kernel/rcu/tree_exp.h:667 1 lock held by syz-executor.2/18663: #0: 00000000024a3640 (&type->s_umount_key#73){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 1 lock held by syz-executor.2/18667: #0: 00000000024a3640 (&type->s_umount_key#73){++++}, at: iterate_supers+0xdb/0x290 fs/super.c:631 2 locks held by syz-executor.2/18673: #0: 0000000045a0dda2 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2779 [inline] #0: 0000000045a0dda2 (sb_writers#3){.+.+}, at: do_sendfile+0x97d/0xc30 fs/read_write.c:1446 #1: 00000000c8835487 (&sb->s_type->i_mutex_key#10){++++}, at: inode_trylock include/linux/fs.h:768 [inline] #1: 00000000c8835487 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_file_write_iter+0x21f/0xf20 fs/ext4/file.c:238 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8162 Comm: syz-executor.0 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:native_apic_mem_write+0x8/0x10 arch/x86/include/asm/apic.h:109 Code: 3d cc 17 3d 0b 01 7f 02 5d c3 89 ef 5d e9 f5 fe c9 06 48 c7 c7 00 97 65 8c e8 84 e2 6f 00 eb df 66 90 89 ff 89 b7 00 c0 5f ff 0f 1f 80 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 53 89 fb 48 RSP: 0018:ffff8880a95afb10 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffff89cfb1a0 RCX: 0000000000000020 RDX: 1ffffffff139f636 RSI: 000000000000ffdd RDI: 0000000000000380 RBP: ffff8880ba01e2c0 R08: ffffffff8c665018 R09: 0000000000000000 R10: 0000000000000007 R11: ffffffff8c66501b R12: 000000000000ffdd R13: 0000000000000000 R14: ffff8880ba024cc0 R15: 0000000000024cc0 FS: 000055555749e400(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3f68aff000 CR3: 00000000b05f2000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:389 [inline] lapic_next_event+0x4d/0x80 arch/x86/kernel/apic/apic.c:460 clockevents_program_event+0x234/0x350 kernel/time/clockevents.c:344 tick_program_event+0xac/0x140 kernel/time/tick-oneshot.c:48 hrtimer_reprogram+0x386/0x430 kernel/time/hrtimer.c:861 hrtimer_start_range_ns+0x72f/0xd60 kernel/time/hrtimer.c:1183 hrtimer_start_expires include/linux/hrtimer.h:412 [inline] do_nanosleep+0x1fe/0x6c0 kernel/time/hrtimer.c:1752 hrtimer_nanosleep+0x24d/0x570 kernel/time/hrtimer.c:1809 common_nsleep+0x23/0x30 kernel/time/posix-timers.c:1204 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1231 [inline] __se_sys_clock_nanosleep+0x261/0x360 kernel/time/posix-timers.c:1209 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f11c6b8c361 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 aa e7 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 e3 e7 ff ff 48 8b 04 24 eb 97 66 2e 0f 1f RSP: 002b:00007ffd9af57270 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000309 RCX: 00007f11c6b8c361 RDX: 00007ffd9af572b0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffd9af5733c R08: 0000000000000000 R09: 00000081769f7548 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000007a9ae R14: 0000000000000003 R15: 00007ffd9af573a0