INFO: task syz-executor.1:5086 blocked for more than 143 seconds. Not tainted 6.8.0-rc3-syzkaller-00005-g99bd3cb0d12e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:19704 pid:5086 tgid:5086 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x177f/0x49a0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 wb_wait_for_completion+0x166/0x290 fs/fs-writeback.c:192 sync_inodes_sb+0x293/0xb20 fs/fs-writeback.c:2758 sync_filesystem+0x176/0x230 fs/sync.c:64 generic_shutdown_super+0x72/0x2d0 fs/super.c:625 kill_block_super+0x44/0x90 fs/super.c:1680 xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2026 deactivate_locked_super+0xc4/0x130 fs/super.c:477 cleanup_mnt+0x426/0x4c0 fs/namespace.c:1267 task_work_run+0x24e/0x310 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:108 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0x167/0x370 kernel/entry/common.c:212 do_syscall_64+0x108/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7fa829e7f0d7 RSP: 002b:00007ffc0695c728 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa829e7f0d7 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffc0695c7e0 RBP: 00007ffc0695c7e0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc0695d8a0 R13: 00007fa829ec93b9 R14: 000000000017db39 R15: 0000000000000002 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 2 locks held by kworker/u4:5/956: #0: ffff8880b943c918 ( &rq->__lock ){-.-.}-{2:2} , at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 #1: ffff8880b9428988 ( &per_cpu_ptr(group->pcpu, cpu)->seq ){-.-.}-{0:0} , at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:988 4 locks held by kworker/u4:7/2416: #0: ffff888019299d38 ( (wq_completion)writeback ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:2608 [inline] , at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc9000980fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffff888022588610 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x267/0x1320 fs/xfs/libxfs/xfs_bmap.c:4542 #3: ffff8880741d6d98 (&xfs_nondir_ilock_class#3){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x295/0x1320 fs/xfs/libxfs/xfs_bmap.c:4547 2 locks held by getty/4808: #0: ffff88802b6430a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002efe2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 2 locks held by syz-executor.1/5086: #0: ffff8880225880e0 (&type->s_umount_key#57){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880225880e0 (&type->s_umount_key#57){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880225880e0 (&type->s_umount_key#57){++++}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:509 #1: ffff8880201327d0 (&bdi->wb_switch_rwsem ){+.+.}-{3:3} , at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline] , at: sync_inodes_sb+0x274/0xb20 fs/fs-writeback.c:2756 6 locks held by kworker/0:3/5129: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc3-syzkaller-00005-g99bd3cb0d12e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4491 Comm: syslogd Not tainted 6.8.0-rc3-syzkaller-00005-g99bd3cb0d12e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 RIP: 0010:check_kcov_mode kernel/kcov.c:175 [inline] RIP: 0010:write_comp_data kernel/kcov.c:236 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x2e/0x90 kernel/kcov.c:304 Code: 4c 8b 04 24 65 48 8b 15 40 54 70 7e 65 8b 05 41 54 70 7e a9 00 01 ff 00 74 10 a9 00 01 00 00 74 5b 83 ba fc 15 00 00 00 74 52 <8b> 82 d8 15 00 00 83 f8 03 75 47 48 8b 8a e0 15 00 00 44 8b 8a dc RSP: 0018:ffffc90002ea7e18 EFLAGS: 00000246 RAX: 0000000080000000 RBX: 0000000000200000 RCX: ffff88807d5fbb80 RDX: ffff88807d5fbb80 RSI: 0000000000200000 RDI: 0000000000000000 RBP: ffffc90002ea7f00 R08: ffffffff82029eb1 R09: 1ffff11005deef08 R10: dffffc0000000000 R11: ffffed1005deef09 R12: ffff88802f131680 R13: 00000000082e0003 R14: ffff88802f131680 R15: ffff88802f131680 FS: 00007f91ea8b0380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555ee68d1010 CR3: 000000002e84a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: file_ppos fs/read_write.c:605 [inline] ksys_read+0x101/0x2c0 fs/read_write.c:614 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f91eaa04b6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffca885ee58 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f91eaa04b6a RDX: 00000000000000ff RSI: 0000560fb5795950 RDI: 0000000000000000 RBP: 0000560fb5795910 R08: 0000000000000001 R09: 0000000000000000 R10: 00007f91eaba33a3 R11: 0000000000000246 R12: 0000560fb579599a R13: 0000560fb5795950 R14: 0000000000000000 R15: 00007f91eabe1a80