INFO: task kworker/u8:6:1319 blocked for more than 143 seconds. Not tainted 6.13.0-rc6-next-20250107-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:6 state:D stack:21368 pid:1319 tgid:1319 ppid:2 flags:0x00004000 Workqueue: events_unbound netfs_write_collection_worker Call Trace: context_switch kernel/sched/core.c:5371 [inline] __schedule+0x18f6/0x4cd0 kernel/sched/core.c:6758 __schedule_loop kernel/sched/core.c:6835 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6850 bit_wait+0x12/0xd0 kernel/sched/wait_bit.c:237 __wait_on_bit+0xb0/0x2f0 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0x1d5/0x260 kernel/sched/wait_bit.c:64 wait_on_bit include/linux/wait_bit.h:77 [inline] netfs_retry_writes+0x16e/0x19b0 fs/netfs/write_retry.c:215 netfs_collect_write_results fs/netfs/write_collect.c:352 [inline] netfs_write_collection_worker+0x2f90/0x3bb0 fs/netfs/write_collect.c:374 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task syz.0.18:5990 blocked for more than 144 seconds. Not tainted 6.13.0-rc6-next-20250107-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.18 state:D stack:23632 pid:5990 tgid:5986 ppid:5832 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5371 [inline] __schedule+0x18f6/0x4cd0 kernel/sched/core.c:6758 __schedule_loop kernel/sched/core.c:6835 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6850 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6907 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 netfs_writepages+0x12b/0x9e0 fs/netfs/write_issue.c:564 do_writepages+0x35f/0x880 mm/page-writeback.c:2683 filemap_fdatawrite_wbc mm/filemap.c:389 [inline] __filemap_fdatawrite_range mm/filemap.c:422 [inline] __filemap_fdatawrite mm/filemap.c:428 [inline] filemap_fdatawrite+0x1f3/0x2a0 mm/filemap.c:433 v9fs_dir_release+0x151/0x560 fs/9p/vfs_dir.c:219 __fput+0x3e9/0x9f0 fs/file_table.c:450 task_work_run+0x24f/0x310 kernel/task_work.c:227 get_signal+0x15f7/0x1750 kernel/signal.c:2790 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc066185d29 RSP: 002b:00007fc0670a6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: 00000000002f0000 RBX: 00007fc066375fa0 RCX: 00007fc066185d29 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000008 RBP: 00007fc066201b08 R08: 0000000000000000 R09: 0000000000000000 R10: 000000007ffff000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc066375fa0 R15: 00007fff46d582f8 INFO: task syz.0.18:5993 blocked for more than 145 seconds. Not tainted 6.13.0-rc6-next-20250107-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.18 state:D stack:26712 pid:5993 tgid:5986 ppid:5832 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5371 [inline] __schedule+0x18f6/0x4cd0 kernel/sched/core.c:6758 __schedule_loop kernel/sched/core.c:6835 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6850 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6907 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 netfs_writepages+0x12b/0x9e0 fs/netfs/write_issue.c:564 do_writepages+0x35f/0x880 mm/page-writeback.c:2683 filemap_fdatawrite_wbc mm/filemap.c:389 [inline] __filemap_fdatawrite_range mm/filemap.c:422 [inline] __filemap_fdatawrite mm/filemap.c:428 [inline] filemap_fdatawrite+0x1f3/0x2a0 mm/filemap.c:433 v9fs_vfs_setattr+0x7e5/0xe20 fs/9p/vfs_inode.c:1072 notify_change+0xbca/0xe90 fs/attr.c:552 vfs_utimes+0x4b5/0x770 fs/utimes.c:66 do_utimes_path fs/utimes.c:99 [inline] do_utimes fs/utimes.c:140 [inline] do_futimesat fs/utimes.c:194 [inline] __do_sys_utimes fs/utimes.c:207 [inline] __se_sys_utimes+0x194/0x380 fs/utimes.c:204 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc066185d29 RSP: 002b:00007fc067064038 EFLAGS: 00000246 ORIG_RAX: 00000000000000eb RAX: ffffffffffffffda RBX: 00007fc066376160 RCX: 00007fc066185d29 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000180 RBP: 00007fc066201b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fc066376160 R15: 00007fff46d582f8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 2 locks held by kworker/u8:6/1319: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000469fc60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000469fc60 ((work_completion)(&rreq->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 2 locks held by dhcpcd/5497: #0: ffffffff8fca0b88 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x661/0x8e0 net/socket.c:1301 #1: ffffffff8fcbb6c8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0x112/0x9d0 net/8021q/vlan.c:553 2 locks held by getty/5592: #0: ffff88803544a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:5/5881: #0: ffff88801ac80d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000473fc60 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000473fc60 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcbb6c8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/u8:8/5967: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90004defc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90004defc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcbb6c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281 1 lock held by syz.0.18/5990: #0: ffff88805d3c8500 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0x12b/0x9e0 fs/netfs/write_issue.c:564 1 lock held by syz.0.18/5991: #0: ffff88805d3c8500 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0xcf/0x9e0 fs/netfs/write_issue.c:558 3 locks held by syz.0.18/5993: #0: ffff888034946420 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:547 #1: ffff88805d3c8148 (&sb->s_type->i_mutex_key#23){++++}-{4:4}, at: inode_lock include/linux/fs.h:865 [inline] #1: ffff88805d3c8148 (&sb->s_type->i_mutex_key#23){++++}-{4:4}, at: vfs_utimes+0x44d/0x770 fs/utimes.c:65 #2: ffff88805d3c8500 (&ctx->wb_lock){+.+.}-{4:4}, at: netfs_writepages+0x12b/0x9e0 fs/netfs/write_issue.c:564 4 locks held by kworker/u8:27/6861: 3 locks held by kworker/u8:34/6934: 2 locks held by syz-executor/7819: #0: ffffffff901b04e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff901b04e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff901b04e0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555 #1: ffffffff8fcbb6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fcbb6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #1: ffffffff8fcbb6c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xce2/0x2210 net/core/rtnetlink.c:4011 1 lock held by syz.1.410/7852: 2 locks held by syz.4.411/7854: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc6-next-20250107-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7854 Comm: syz.4.411 Not tainted 6.13.0-rc6-next-20250107-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:416 Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 6c 86 af fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7 RSP: 0018:ffffc9000bae6b10 EFLAGS: 00000002 RAX: 000000000000005b RBX: ffffffff9a728080 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 000000000007ffff RDI: 0000000000080000 RBP: 0000000000000000 R08: ffffffff8576029b R09: 1ffff11004a43046 R10: dffffc0000000000 R11: ffffffff85760250 R12: dffffc0000000000 R13: ffffffff9a422f21 R14: 000000000000005b R15: 00000000000003f8 FS: 00007f7f292356c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7f1ebff000 CR3: 0000000057974000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial8250_console_write+0x14ed/0x1ed0 drivers/tty/serial/8250/8250_port.c:3418 console_emit_next_record kernel/printk/printk.c:3122 [inline] console_flush_all+0x869/0xeb0 kernel/printk/printk.c:3210 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432 _printk+0xd5/0x120 kernel/printk/printk.c:2457 set_capacity_and_notify+0x1ae/0x240 block/genhd.c:86 loop_set_size+0x44/0xb0 drivers/block/loop.c:232 loop_configure+0x9ec/0xeb0 drivers/block/loop.c:1101 lo_ioctl+0x846/0x1f50 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7f2838592b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007f7f29234dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f7f2838592b RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000005598 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f7f29234ef0 R14: 00007f7f29234eb0 R15: 00007f7f1dc00000