syzbot

INFO: task syz.4.5466:26023 blocked for more than 144 seconds.
      Not tainted 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.5466      state:D stack:26920 pid:26023 tgid:26023 ppid:25480  task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5401 [inline]
 __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6790
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6883
 request_wait_answer fs/fuse/dev.c:565 [inline]
 __fuse_request_send fs/fuse/dev.c:579 [inline]
 __fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:673
 fuse_simple_request fs/fuse/fuse_i.h:1237 [inline]
 fuse_flush+0x5d4/0x800 fs/fuse/file.c:475
 filp_flush+0xba/0x190 fs/open.c:1549
 filp_close+0x1d/0x40 fs/open.c:1562
 __range_close fs/file.c:752 [inline]
 __do_sys_close_range fs/file.c:811 [inline]
 __se_sys_close_range+0x359/0x650 fs/file.c:775
 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: 0033:0x7f378e78e929
RSP: 002b:00007ffcea7311c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 000000000020cd03 RCX: 00007f378e78e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f378e9b7ba0 R08: 0000000000000001 R09: 0000000cea7314bf
R10: 00007f378e600000 R11: 0000000000000246 R12: 00007f378e9b5fac
R13: 00007f378e9b5fa0 R14: ffffffffffffffff R15: 00007ffcea7312e0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5599:
 #0: ffff88814dba00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
5 locks held by kworker/0:6/5924:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc9000449fbc0 ((work_completion)(&rdev->destroy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000449fbc0 ((work_completion)(&rdev->destroy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffffffff8f50b548 (rtnl_mutex){+.+.}-{4:4}, at: cfg80211_destroy_iface_wk+0x19/0x30 net/wireless/core.c:360
 #3: ffff88804ef40768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline]
 #3: ffff88804ef40768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_destroy_ifaces+0x112/0x1b0 net/wireless/core.c:345
 #4: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
 #4: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
3 locks held by kworker/0:5/17010:
2 locks held by kworker/u8:20/19076:
3 locks held by kworker/u8:22/19079:
 #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc9000d537bc0 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000d537bc0 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffff88804ef40768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6062 [inline]
 #2: ffff88804ef40768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xc4/0x460 net/wireless/core.c:421
1 lock held by syz.7.5835/27451:
 #0: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17010 Comm: kworker/0:5 Not tainted 6.16.0-rc5-syzkaller-00121-gbc9ff192a6c9 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:mark_held_locks kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__trace_hardirqs_on_caller kernel/locking/lockdep.c:4346 [inline]
RIP: 0010:lockdep_hardirqs_on_prepare+0xe7/0x2a0 kernel/locking/lockdep.c:4413
Code: 8d e8 8d 0c ca 09 65 ff 05 96 29 ff 10 83 bb e8 0a 00 00 00 0f 8e d1 00 00 00 49 89 de 49 81 c6 f0 0a 00 00 45 31 ff 4d 89 f4 <eb> 13 49 ff c7 48 63 83 e8 0a 00 00 49 83 c4 28 49 39 c7 7d 44 49
RSP: 0018:ffffc90003c6f820 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888026911e00 RCX: d1da36a3712e8c00
RDX: 0000000000000000 RSI: ffffffff8d998a0b RDI: ffffffff8be1ca40
RBP: ffffc90003c6f910 R08: ffffffff8fa0c9f7 R09: 1ffffffff1f4193e
R10: dffffc0000000000 R11: fffffbfff1f4193f R12: ffff8880269128f0
R13: ffff88802775cd18 R14: ffff8880269128f0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125c4f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fafd5581ab8 CR3: 0000000033f4a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:78
 native_save_fl arch/x86/include/asm/irqflags.h:19 [inline]
 arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
 arch_irqs_disabled arch/x86/include/asm/irqflags.h:151 [inline]
 seqcount_lockdep_reader_access+0x123/0x1c0 include/linux/seqlock.h:74
 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:333 [inline]
 gc_worker+0x308/0x1380 net/netfilter/nf_conntrack_core.c:1537
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/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
 </TASK>