INFO: task syz.0.4233:23540 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller-11061-g7f9039c524a3 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4233 state:D stack:24488 pid:23540 tgid:23532 ppid:21984 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6874
super_lock+0x1c8/0x3b0 fs/super.c:115
__iterate_supers+0x126/0x250 fs/super.c:923
drop_caches_sysctl_handler+0x97/0x170 fs/drop_caches.c:64
proc_sys_call_handler+0x50c/0x7c0 fs/proc/proc_sysctl.c:601
iter_file_splice_write+0x93a/0x1000 fs/splice.c:738
do_splice_from fs/splice.c:935 [inline]
direct_splice_actor+0x101/0x160 fs/splice.c:1158
splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1102
do_splice_direct_actor fs/splice.c:1201 [inline]
do_splice_direct+0x181/0x270 fs/splice.c:1227
do_sendfile+0x4da/0x7e0 fs/read_write.c:1370
__do_sys_sendfile64 fs/read_write.c:1425 [inline]
__se_sys_sendfile64+0xd9/0x190 fs/read_write.c:1417
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f76e898e969
RSP: 002b:00007f76e9761038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f76e8bb6240 RCX: 00007f76e898e969
RDX: 0000200000002080 RSI: 000000000000000d RDI: 000000000000000e
RBP: 00007f76e8a10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 100000000000023b R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f76e8bb6240 R15: 00007ffc02f664f8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f080 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f080 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f080 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5587:
#0: ffff8880351920a0 (&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+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/0:6/5901:
#0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000214fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000214fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88805fdc2538 (&idev->mc_lock){+.+.}-{4:4}, at: mld_ifc_work+0x2d/0xde0 net/ipv6/mcast.c:2701
2 locks held by kworker/u8:14/17021:
8 locks held by kworker/u8:15/20678:
#0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900038cfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900038cfbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f500a90 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662
#3: ffff888144ad60e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff888144ad60e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff888144ad60e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506
#4: ffff88805fbac250 (&devlink->lock_key#37){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
#4: ffff88805fbac250 (&devlink->lock_key#37){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff88805fbac250 (&devlink->lock_key#37){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506
#5: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xdb/0x670 drivers/net/netdevsim/netdev.c:1063
#6: ffff8880330d4d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2756 [inline]
#6: ffff8880330d4d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x5a1/0x2320 net/core/dev.c:12035
#7: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#7: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz-executor/21071:
#0: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144bb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.4.3910/22415:
1 lock held by syz.0.4233/23540:
#0: ffff888070322428 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1157
3 locks held by syz-executor/24379:
#0: ffffffff8f5737f0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8f573608 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff8f573608 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff8f573608 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209
#2: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: ieee80211_register_hw+0x3416/0x4120 net/mac80211/main.c:1598
2 locks held by syz-executor/24787:
#0: ffffffff8f500a90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:570
#1: ffffffff8f50d688 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1c/0x1d0 drivers/net/wireguard/device.c:416
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-11061-g7f9039c524a3 #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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:464
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: 10262 Comm: kworker/1:4 Not tainted 6.15.0-syzkaller-11061-g7f9039c524a3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events free_obj_work
RIP: 0010:unwind_get_return_address+0x63/0x90 arch/x86/kernel/unwind_orc.c:369
Code: 37 00 74 08 48 89 df e8 4b 48 b1 00 48 8b 3b e8 43 a4 1a 00 85 c0 74 14 43 80 3c 37 00 74 08 48 89 df e8 30 48 b1 00 48 8b 03 02 31 c0 5b 41 5e 41 5f e9 7a a4 9d ff cc 89 d9 80 e1 07 80 c1
RSP: 0018:ffffc9000fc07588 EFLAGS: 00000246
RAX: ffffffff81333f4a RBX: ffffc9000fc075f0 RCX: 52f9289b16d6e300
RDX: 0000000000000001 RSI: ffffffff8db5d4ed RDI: ffffffff81333f4a
RBP: ffffc9000fc07630 R08: ffffc9000fc07f48 R09: ffffc9000fc075f8
R10: dffffc0000000000 R11: fffff52001f80ec1 R12: ffff888030969e00
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001f80ebe
FS: 0000000000000000(0000) GS:ffff888125d5e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000588 CR3: 000000004dfad000 CR4: 0000000000350ef0
Call Trace:
arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2380 [inline]
slab_free mm/slub.c:4642 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4744
free_object_list lib/debugobjects.c:326 [inline]
free_obj_work+0x342/0x480 lib/debugobjects.c:513
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245