INFO: task syz-executor:14674 blocked for more than 143 seconds.
Not tainted 6.1.131-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21192 pid:14674 ppid:1 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5243 [inline]
__schedule+0x143f/0x4570 kernel/sched/core.c:6560
schedule+0xbf/0x180 kernel/sched/core.c:6636
wb_wait_for_completion+0x162/0x290 fs/fs-writeback.c:191
sync_inodes_sb+0x28f/0xb10 fs/fs-writeback.c:2739
sync_filesystem+0x16b/0x220 fs/sync.c:64
generic_shutdown_super+0x6b/0x340 fs/super.c:474
kill_block_super+0x7a/0xe0 fs/super.c:1470
deactivate_locked_super+0xa0/0x110 fs/super.c:332
cleanup_mnt+0x490/0x520 fs/namespace.c:1186
task_work_run+0x246/0x300 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0xa6e/0x26a0 kernel/exit.c:871
do_group_exit+0x202/0x2b0 kernel/exit.c:1021
__do_sys_exit_group kernel/exit.c:1032 [inline]
__se_sys_exit_group kernel/exit.c:1030 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1030
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4f6778d169
RSP: 002b:00007ffd4b7d97c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f4f6780e0fe RCX: 00007f4f6778d169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000010 R08: 00007ffd4b7d7566 R09: 00007ffd4b7daa80
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd4b7daa80
R13: 00007f4f6780e08c R14: 00005555953d44a8 R15: 00007ffd4b7dbb50
</TASK>
Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
#0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc900000e7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffffffff8e543a50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xd20 net/core/net_namespace.c:594
#3: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe5/0xa20 net/core/dev.c:11477
3 locks held by kworker/u4:1/11:
#0: ffff888017c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc90000107d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8d32e890 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8d32f090 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
3 locks held by kworker/u4:5/2967:
2 locks held by getty/4016:
#0: ffff888030c3a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198
3 locks held by kworker/1:6/4297:
#0: ffff88814cf62d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc90003f57d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16e0 net/ipv6/addrconf.c:4134
3 locks held by kworker/u4:6/4310:
4 locks held by kworker/u4:7/4323:
2 locks held by kworker/0:11/4455:
#0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc90004cafd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
3 locks held by kworker/0:15/4463:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc900049f7d20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/0:16/4465:
#0: ffff88814cf62d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#1: ffffc90004d3fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267
#2: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16e0 net/ipv6/addrconf.c:4134
2 locks held by syz-executor/13350:
#0: ffff8880550ec0e0 (&type->s_umount_key#31){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362
#1: ffff888143fc27d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff888143fc27d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x270/0xb10 fs/fs-writeback.c:2737
2 locks held by syz-executor/14674:
#0: ffff8880792220e0 (&type->s_umount_key#31){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362
#1: ffff888024d007d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
#1: ffff888024d007d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x270/0xb10 fs/fs-writeback.c:2737
3 locks held by kworker/u4:18/15336:
1 lock held by syz-executor/16499:
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147
7 locks held by syz-executor/16626:
#0: ffff88807f09c460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580
#1: ffff8880757ffc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325
#2: ffff88814577b660 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:326
#3: ffffffff8de618a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xf8/0x480 drivers/net/netdevsim/bus.c:209
#4: ffff88807ce800e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline]
#4: ffff88807ce800e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline]
#4: ffff88807ce800e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb6/0x880 drivers/base/dd.c:1283
#5: ffff88807ce852f8 (&devlink->lock_key#37){+.+.}-{3:3}, at: nsim_drv_remove+0x54/0x160 drivers/net/netdevsim/dev.c:1677
#6: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3a/0x140 drivers/net/netdevsim/netdev.c:381
4 locks held by syz-executor/16630:
#0: ffff88807f09c460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x269/0xbc0 fs/read_write.c:580
#1: ffff88805cd6f488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e7/0x4f0 fs/kernfs/file.c:325
#2: ffff88814577b578 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20b/0x4f0 fs/kernfs/file.c:326
#3: ffffffff8de618a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1ad/0x800 drivers/net/netdevsim/bus.c:160
1 lock held by syz-executor/16632:
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147
1 lock held by syz.6.3662/16746:
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147
1 lock held by syz.6.3662/16747:
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147
1 lock held by syz.6.3662/16748:
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7cb/0x1000 net/core/rtnetlink.c:6147
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.131-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1ca/0x430 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf88/0xfd0 kernel/hung_task.c:377
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4323 Comm: kworker/u4:7 Not tainted 6.1.131-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: writeback wb_workfn (flush-7:2)
RIP: 0010:unwind_next_frame+0x551/0x2220 arch/x86/kernel/unwind_orc.c:461
Code: 0f b6 04 38 84 c0 0f 85 1d 17 00 00 c6 03 01 48 c7 c5 60 91 09 8b 4c 8d 6d 04 48 8d 5d 05 4d 89 ef 49 c1 ef 03 41 0f b6 04 3f <84> c0 0f 85 92 16 00 00 48 89 d8 48 c1 e8 03 0f b6 04 38 84 c0 0f
RSP: 0018:ffffc90003fb6a00 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffffff8f2a4e4d RCX: ffffffff8eb902ac
RDX: ffffffff8f2a4e48 RSI: ffffffff81fda8c7 RDI: dffffc0000000000
RBP: ffffffff8f2a4e48 R08: 0000000000000001 R09: ffffc90003fb6bd0
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffffffff8f2a4e4c R14: ffffffff8eb902a8 R15: 1ffffffff1e549c9
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcc5a22318d CR3: 000000000d08e000 CR4: 00000000003506e0
Call Trace:
<NMI>
</NMI>
<TASK>
arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1724 [inline]
slab_free_freelist_hook mm/slub.c:1750 [inline]
slab_free mm/slub.c:3661 [inline]
kmem_cache_free+0x292/0x510 mm/slub.c:3683
ext4_writepages+0xd0f/0x3de0 fs/ext4/inode.c:2813
do_writepages+0x3a2/0x670 mm/page-writeback.c:2491
__writeback_single_inode+0x15d/0x11e0 fs/fs-writeback.c:1612
writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903
wb_writeback+0x49d/0xe10 fs/fs-writeback.c:2077
wb_do_writeback fs/fs-writeback.c:2220 [inline]
wb_workfn+0x427/0x1020 fs/fs-writeback.c:2260
process_one_work+0x917/0x1260 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>