INFO: task syz-executor:6893 blocked for more than 143 seconds.
Not tainted 6.14.0-syzkaller-00826-g327ecdbc0fda #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21480 pid:6893 tgid:6893 ppid:1 task_flags:0x40014c flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5367 [inline]
__schedule+0x1b13/0x50e0 kernel/sched/core.c:6748
__schedule_loop kernel/sched/core.c:6825 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6840
wb_wait_for_completion+0x164/0x270 fs/fs-writeback.c:216
sync_inodes_sb+0x28d/0xb50 fs/fs-writeback.c:2821
sync_filesystem+0x176/0x230 fs/sync.c:64
generic_shutdown_super+0x72/0x2d0 fs/super.c:621
kill_block_super+0x44/0x90 fs/super.c:1710
ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7368
deactivate_locked_super+0xc6/0x130 fs/super.c:473
cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1435
task_work_run+0x251/0x310 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2a/0x2940 kernel/exit.c:954
do_group_exit+0x207/0x2c0 kernel/exit.c:1103
__do_sys_exit_group kernel/exit.c:1114 [inline]
__se_sys_exit_group kernel/exit.c:1112 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1112
x64_sys_call+0x26c3/0x26d0 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7f6453b8d169
RSP: 002b:00007ffcd7f74848 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f6453c0e0fe RCX: 00007f6453b8d169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000010 R08: 00007ffcd7f725e6 R09: 00007ffcd7f75b00
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcd7f75b00
R13: 00007f6453c0e08c R14: 00005555681e84a8 R15: 00007ffcd7f76bd0
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0: ffff88814cff8948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814cff8948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc90000127c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000127c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline]
#2: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x10e/0x16a0 net/ipv6/addrconf.c:4190
1 lock held by khungtaskd/31:
#0: ffffffff8eb3a4a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8eb3a4a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8eb3a4a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6761
4 locks held by kworker/u8:2/36:
2 locks held by dhcpcd/5496:
#0: ffffffff8febaa28 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x661/0x8e0 net/socket.c:1280
#1: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0x112/0x9d0 net/8021q/vlan.c:554
4 locks held by kworker/u8:11/6656:
#0: ffff88801baee148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801baee148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc900041d7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900041d7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffffffff8fec92d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17a/0xd60 net/core/net_namespace.c:606
#3: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: mpls_net_exit+0x7d/0x2a0 net/mpls/af_mpls.c:2706
2 locks held by syz-executor/6893:
#0: ffff888051f480e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff888051f480e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff888051f480e0 (&type->s_umount_key#32){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505
#1: ffff8880253847d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880253847d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
2 locks held by getty/7647:
#0: ffff8880311960a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003a552f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/8706:
#0: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline]
#0: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021
1 lock held by syz-executor/8820:
#0: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline]
#0: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021
8 locks held by syz-executor/8843:
#0: ffff888030e4c420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3033 [inline]
#0: ffff888030e4c420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x225/0xd10 fs/read_write.c:680
#1: ffff88807d724888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ef/0x510 fs/kernfs/file.c:325
#2: ffff88814132a008 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x213/0x510 fs/kernfs/file.c:326
#3: ffffffff8f77c508 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
#4: ffff888051b800e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline]
#4: ffff888051b800e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
#4: ffff888051b800e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293
#5: ffff888027c23250 (&devlink->lock_key#12){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675
#6: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xa4/0x620 drivers/net/netdevsim/netdev.c:1016
#7: ffffffff8eb3f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#7: ffffffff8eb3f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:998
2 locks held by syz-executor/9076:
#0: ffffffff8f676fa0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f676fa0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8f676fa0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:564
#1: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline]
#1: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021
2 locks held by syz-executor/9142:
#0: ffffffff903d3800 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff903d3800 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff903d3800 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:564
#1: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline]
#1: ffffffff8fed5b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021
1 lock held by syz.0.633/9191:
#0: ffff888051f480e0 (&type->s_umount_key#32){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888051f480e0 (&type->s_umount_key#32){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-syzkaller-00826-g327ecdbc0fda #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7ab/0x920 kernel/kthread.c:464
ret_from_fork+0x4d/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: 36 Comm: kworker/u8:2 Not tainted 6.14.0-syzkaller-00826-g327ecdbc0fda #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: writeback wb_workfn (flush-7:9)
RIP: 0010:in_lock_functions+0x4/0x30 kernel/locking/spinlock.c:412
Code: ff ff ff 48 c7 c7 a8 00 47 96 e8 57 39 8b 00 e9 62 ff ff ff 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <48> c7 c0 c0 c6 0c 8c 48 39 c7 0f 93 c0 48 c7 c1 aa 00 0d 8c 48 39
RSP: 0018:ffffc90000ac6668 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff9a4a8b03
RDX: dffffc0000000000 RSI: ffffc90000ac8000 RDI: ffffffff816d6530
RBP: ffffc90000ac67f8 R08: ffffc90000ac6801 R09: ffffc90000ac67c0
R10: dffffc0000000000 R11: fffff52000158d04 R12: dffffc0000000000
R13: ffffc90000ac67c0 R14: ffffffff816d6530 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2c820220 CR3: 0000000033e68000 CR4: 0000000000350ef0
Call Trace:
get_lock_parent_ip include/linux/ftrace.h:1089 [inline]
preempt_latency_start kernel/sched/core.c:5823 [inline]
preempt_count_add+0x93/0x190 kernel/sched/core.c:5848
unwind_next_frame+0xb0/0x22d0 arch/x86/kernel/unwind_orc.c:479
__unwind_start+0x59a/0x740 arch/x86/kernel/unwind_orc.c:760
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe5/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:319 [inline]
__kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4138 [inline]
slab_alloc_node mm/slub.c:4187 [inline]
kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4194
ext4_init_io_end+0x29/0x130 fs/ext4/page-io.c:277
ext4_do_writepages+0xbe6/0x3df0 fs/ext4/inode.c:2683
ext4_writepages+0x213/0x3c0 fs/ext4/inode.c:2824
do_writepages+0x361/0x880 mm/page-writeback.c:2687
__writeback_single_inode+0x14f/0x10d0 fs/fs-writeback.c:1680
writeback_sb_inodes+0x820/0x1360 fs/fs-writeback.c:1976
wb_writeback+0x413/0xb80 fs/fs-writeback.c:2156
wb_do_writeback fs/fs-writeback.c:2303 [inline]
wb_workfn+0x410/0x1080 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac0/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd30 kernel/workqueue.c:3400
kthread+0x7ab/0x920 kernel/kthread.c:464
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244