NILFS (loop0): broken superblock, retrying with spare superblock (blocksize = 2048) NILFS (loop0): mounting unchecked fs NILFS (loop0): recovery complete NILFS (loop0): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds INFO: task syz-executor115:6497 blocked for more than 140 seconds. Not tainted 4.19.150-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor115 D27792 6497 6491 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x8e5/0x22e0 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 wb_wait_for_completion+0x175/0x1f0 fs/fs-writeback.c:222 sync_inodes_sb+0x19d/0xa20 fs/fs-writeback.c:2483 __sync_filesystem fs/sync.c:34 [inline] sync_filesystem+0x15c/0x250 fs/sync.c:67 generic_shutdown_super+0x70/0x370 fs/super.c:442 kill_block_super+0x97/0xf0 fs/super.c:1185 deactivate_locked_super+0x8c/0x100 fs/super.c:329 deactivate_super+0x174/0x1a0 fs/super.c:360 cleanup_mnt+0x1da/0x300 fs/namespace.c:1098 task_work_run+0x141/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x269/0x2c0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x57c/0x670 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x44e0f7 Code: Bad RIP value. RSP: 002b:00007ffcdcc3ee78 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00000000000ccd22 RCX: 000000000044e0f7 RDX: 0000000000400d27 RSI: 0000000000000002 RDI: 00007ffcdcc3ef20 RBP: 0000000000001962 R08: 0000000000000000 R09: 0000000000000009 R10: 0000000000000005 R11: 0000000000000202 R12: 00007ffcdcc3ffd0 R13: 00000000020ff880 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/1095: #0: 0000000021f2c890 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x291 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6175: #0: 000000009c92d6ec (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:767 2 locks held by syz-executor115/6497: #0: 0000000014b5a469 (&type->s_umount_key#59){+.+.}, at: deactivate_super+0x16c/0x1a0 fs/super.c:359 #1: 000000004ec73461 (&bdi->wb_switch_rwsem){+.+.}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline] #1: 000000004ec73461 (&bdi->wb_switch_rwsem){+.+.}, at: sync_inodes_sb+0x180/0xa20 fs/fs-writeback.c:2481 2 locks held by kworker/u4:0/6504: #0: 0000000078c7b08b ((wq_completion)"writeback"){+.+.}, at: process_one_work+0x692/0x14e0 kernel/workqueue.c:2126 #1: 00000000fc6b733d ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: process_one_work+0x6c8/0x14e0 kernel/workqueue.c:2130 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1095 Comm: khungtaskd Not tainted 4.19.150-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x22c/0x33e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x18/0x3d lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb 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+0xa62/0x1020 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: 3718 Comm: systemd-journal Not tainted 4.19.150-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x22/0x50 kernel/kcov.c:101 Code: 00 00 e9 39 ec ff ff 90 48 8b 34 24 65 48 8b 04 25 40 ee 01 00 65 8b 15 5c 1b 90 7e 81 e2 00 01 1f 00 75 2b 8b 90 e0 12 00 00 <83> fa 02 75 20 48 8b 88 e8 12 00 00 8b 80 e4 12 00 00 48 8b 11 48 RSP: 0018:ffff8880942a7dd8 EFLAGS: 00000246 RAX: ffff888093cd2180 RBX: ffff888094b3c3c0 RCX: ffffffff81bd6094 RDX: 0000000000000000 RSI: ffffffff81bd60a2 RDI: 0000000000000004 RBP: 0000000000000014 R08: 0000000000000001 R09: 0000000000000040 R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000040 R13: ffff888094b3c418 R14: 0000000000000000 R15: 0000000000004000 FS: 00007fd86f11b8c0(0000) GS:ffff8880ae200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd86c4c5000 CR3: 0000000094246000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: find_next_fd fs/file.c:472 [inline] __alloc_fd+0x1e2/0x590 fs/file.c:495 do_sys_open+0x297/0x520 fs/open.c:1083 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fd86e6ab840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffd093268d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffd09326be0 RCX: 00007fd86e6ab840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000560ee3d17ab0 RBP: 000000000000000d R08: 000000000000c0ff R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000560ee3d0c060 R14: 00007ffd09326ba0 R15: 0000560ee3d18f80