INFO: task kworker/u8:8:3503 blocked for more than 143 seconds.
Not tainted 6.16.0-rc5-next-20250709-syzkaller-08296-g835244aba90d #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:8 state:D stack:23320 pid:3503 tgid:3503 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
context_switch kernel/sched/core.c:5314 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6697
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6847
rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088
__down_read_common kernel/locking/rwsem.c:1263 [inline]
__down_read kernel/locking/rwsem.c:1276 [inline]
down_read_nested+0x9a/0x2f0 kernel/locking/rwsem.c:1665
xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
iomap_writepage_map_blocks fs/iomap/buffered-io.c:1772 [inline]
iomap_writepage_map fs/iomap/buffered-io.c:1922 [inline]
iomap_writepages+0x10df/0x3240 fs/iomap/buffered-io.c:1976
xfs_vm_writepages+0x235/0x2b0 fs/xfs/xfs_aops.c:650
do_writepages+0x32e/0x550 mm/page-writeback.c:2634
__writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1680
writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:1976
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0:
ffffffff8e13c420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
ffffffff8e13c420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
ffffffff8e13c420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
4 locks held by kworker/u8:2/36:
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc90000ac7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc90000ac7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff8880766400e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888053d9b758 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
4 locks held by kworker/u8:3/48:
4 locks held by kworker/u8:4/68:
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc9000214fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc9000214fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff888057c7c0e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888053dace98 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
4 locks held by kworker/u8:7/1148:
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc90003e2fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc90003e2fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff8880582c00e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88807297a018 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
4 locks held by kworker/u8:8/3503:
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc9000cbf7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc9000cbf7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff88807b5340e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88805add3f18 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
2 locks held by getty/5607:
#0: ffff88814d58d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by syz.4.26/6965:
#0: ffff88807b534428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88805add4130 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff88805add4130 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff88807b534618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1098
#3: ffff88805add3f18 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1104
4 locks held by syz.2.59/7473:
4 locks held by syz.0.112/8271:
#0: ffff8880582c0428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88807297a230 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff88807297a230 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff8880582c0618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1098
#3: ffff88807297a018 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1104
4 locks held by syz.7.176/9105:
#0: ffff88807c9fa428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88805af312b0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff88805af312b0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff88807c9fa618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1098
#3: ffff88805af31098 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1104
4 locks held by syz.5.178/9113:
#0: ffff888057c7c428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888053dad0b0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff888053dad0b0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff888057c7c618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1098
#3: ffff888053dace98 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1104
4 locks held by kworker/u8:10/9622:
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc9000c8d7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc9000c8d7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff88807c9fa0e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88805af31098 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
4 locks held by syz.1.227/9657:
#0: ffff888023dce428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888072978af0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff888072978af0 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff888023dce618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1098
#3: ffff8880729788d8 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1104
4 locks held by kworker/u8:11/9859:
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801faa6148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc90003f4fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc90003f4fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff888023dce0e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff8880729788d8 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
4 locks held by syz.6.264/10051:
#0: ffff888076640428 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888053d9b970 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff888053d9b970 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff888076640618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1098
#3: ffff888053d9b758 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1104
1 lock held by syz.9.385/10931:
2 locks held by syz.3.383/10930:
3 locks held by syz.8.382/10933:
2 locks held by syz.4.387/10935:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-next-20250709-syzkaller-08296-g835244aba90d #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: kauditd Not tainted 6.16.0-rc5-next-20250709-syzkaller-08296-g835244aba90d #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rb_first+0x2f/0x70 lib/rbtree.c:471
Code: 57 41 56 53 48 89 fb 49 bf 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 e4 31 b0 f6 48 8b 03 <48> 85 c0 75 18 31 db 48 89 d8 5b 41 5e 41 5f e9 cd 49 07 00 cc 49
RSP: 0018:ffffc90000a08b50 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88807437a950 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff88807437a950
RBP: ffffc90000a08c90 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014115c R12: 1ffff92000141178
R13: ffff88807437a810 R14: ffff88807437a810 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125cd4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3215ffff CR3: 00000000719c2000 CR4: 00000000003526f0
Call Trace:
mrp_mad_event net/802/mrp.c:584 [inline]
mrp_join_timer+0x34/0x170 net/802/mrp.c:605
call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_flush_all+0x7f7/0xc40 kernel/printk/printk.c:3227
Code: 48 21 c3 0f 85 e9 01 00 00 e8 75 0b 1f 00 48 8b 5c 24 20 4d 85 f6 75 07 e8 66 0b 1f 00 eb 06 e8 5f 0b 1f 00 fb 48 8b 44 24 28 <42> 80 3c 20 00 74 08 48 89 df e8 0a a1 83 00 48 8b 1b 48 8b 44 24
RSP: 0018:ffffc90000a67760 EFLAGS: 00000293
RAX: 1ffffffff1d36c8f RBX: ffffffff8e9b6478 RCX: ffff88801d6a9e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000a678b0 R08: ffffffff8fa35a37 R09: 1ffffffff1f46b46
R10: dffffc0000000000 R11: fffffbfff1f46b47 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000200 R15: ffffffff8e9b6420
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
kauditd_printk_skb kernel/audit.c:546 [inline]
kauditd_hold_skb+0x1c8/0x210 kernel/audit.c:581
kauditd_send_queue+0x2a4/0x2f0 kernel/audit.c:766
kauditd_thread+0x74e/0x9a0 kernel/audit.c:890
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245