INFO: task syz-executor.0:4440 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:22016 pid: 4440 ppid: 1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x1b3/0x920 fs/fs-writeback.c:2781 sync_filesystem+0x16d/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x300 fs/super.c:448 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f796893ac07 RSP: 002b:00007ffd6830b0a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f7968994aa2 RCX: 00007f796893ac07 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffd6830b160 RBP: 00007ffd6830b160 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd6830c220 R13: 00007f7968994aa2 R14: 0000000000011d6f R15: 0000000000000003 Showing all locks held in the system: 5 locks held by kworker/0:0/7: 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 ( rcu_read_lock ){....}-{1:2} , at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:4/1396: #0: ffff888018b90938 ( (wq_completion)writeback ){+.+.}-{0:0} , at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90005507d00 ( (work_completion)(&(&wb->dwork)->work) ){+.+.}-{0:0} , at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff88807a5f6650 ( sb_internal #2 ){.+.+}-{0:0} , at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffffffff8c1111c0 (console_owner){....}-{0:0}, at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 2 locks held by getty/3953: #0: ffff88814c7e1098 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025e62e8 ( &ldata->atomic_read_lock ){+.+.}-{3:3} , at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 2 locks held by syz-executor.0/4440: #0: ffff88807a5f60e0 ( &type->s_umount_key #51 ){+.+.}-{3:3} , at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff8880207227d8 ( &bdi->wb_switch_rwsem ){+.+.}-{3:3} , at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] , at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2779 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 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+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7 Comm: kworker/0:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: xfs-buf/loop0 xfs_buf_ioend_work RIP: 0010:format_decode+0x272/0x1330 lib/vsprintf.c:2567 Code: 00 00 40 00 00 00 eb 2a e8 3b e4 79 fd 49 bf 00 00 00 00 02 00 00 00 eb 19 e8 2a e4 79 fd 49 bf 00 00 00 00 04 00 00 00 eb 08 19 e4 79 fd 49 89 ef 48 8b 44 24 10 0f b6 04 18 84 c0 75 3a 48 RSP: 0018:ffffc90000cc7330 EFLAGS: 00000246 RAX: 0000000000000005 RBX: dffffc0000000000 RCX: 0000000000000001 RDX: ffffffff83fde798 RSI: ffffffff8c73b860 RDI: 0000000000000030 RBP: 0000001000000000 R08: ffff888016a93b80 R09: 0000000000000005 R10: 0000000000000030 R11: 0000000000000000 R12: ffffffff8a0bd2e7 R13: 1ffffffff1417a5c R14: ffffffff8a0bd2e7 R15: 0000000000000010 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e374fe0168 CR3: 0000000023597000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vsnprintf+0xef/0x1a00 lib/vsprintf.c:2763 sprintf+0xd6/0x120 lib/vsprintf.c:3013 print_time kernel/printk/printk.c:1274 [inline] info_print_prefix+0x152/0x300 kernel/printk/printk.c:1300 record_print_text kernel/printk/printk.c:1349 [inline] console_unlock+0x7f5/0x1200 kernel/printk/printk.c:2725 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274 _printk+0xcc/0x110 kernel/printk/printk.c:2299 print_hex_dump+0x1a5/0x260 lib/hexdump.c:285 xfs_hex_dump+0x39/0x50 fs/xfs/xfs_message.c:118 xfs_buf_verifier_error+0x1ba/0x290 fs/xfs/xfs_error.c:418 xfs_allocbt_read_verify+0x53/0xd0 fs/xfs/libxfs/xfs_alloc_btree.c:-1 xfs_buf_ioend+0x25c/0x6e0 fs/xfs/xfs_buf.c:1263 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287