INFO: task syz.5.1747:13175 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1747      state:D stack:28112 pid:13175 tgid:13154 ppid:8646   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 sync_bdevs+0x153/0x480 block/bdev.c:1304
 ksys_sync+0xb0/0xf0 fs/sync.c:105
 __do_sys_sync+0xe/0x20 fs/sync.c:111
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8d2099c799
RSP: 002b:00007f8d21770028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f8d20c16090 RCX: 00007f8d2099c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8d20c16090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8d20c16128 R14: 00007f8d20c16090 R15: 00007ffe7a87cdd8
 </TASK>
INFO: task syz.5.1747:13176 blocked for more than 144 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1747      state:D stack:28136 pid:13176 tgid:13154 ppid:8646   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0xfee/0x6120 kernel/sched/core.c:6911
 __schedule_loop kernel/sched/core.c:6993 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7008
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
 sync_bdevs+0x153/0x480 block/bdev.c:1304
 ksys_sync+0xb0/0xf0 fs/sync.c:105
 __do_sys_sync+0xe/0x20 fs/sync.c:111
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8d2099c799
RSP: 002b:00007f8d1ebf6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f8d20c16180 RCX: 00007f8d2099c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8d20c16180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8d20c16218 R14: 00007f8d20c16180 R15: 00007ffe7a87cdd8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e7e76a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #0: ffffffff8e7e76a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #0: ffffffff8e7e76a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:3/49:
3 locks held by kworker/0:2/792:
 #0: ffff88813fe67148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
 #1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2c11/0x6120 kernel/sched/core.c:6905
 #2: ffffffff8e7e76a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 #2: ffffffff8e7e76a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
 #2: ffffffff8e7e76a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
 #2: ffffffff8e7e76a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x1ea0 arch/x86/kernel/unwind_orc.c:495
1 lock held by klogd/5169:
 #0: ffff8880b843b1a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
 #0: ffff8880b843b1a0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639
2 locks held by getty/5567:
 #0: ffff888038e400a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
3 locks held by kworker/u9:6/5820:
 #0: ffff888079cb6948 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
 #1: ffffc90003f17d08 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
 #2: ffff8880332c8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x18a/0x470 net/bluetooth/hci_sync.c:331
1 lock held by udevd/7244:
 #0: ffff888027499358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
1 lock held by udevd/9784:
 #0: ffff888027624358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
1 lock held by syz.5.1747/13175:
 #0: ffff888027624358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304
1 lock held by syz.5.1747/13176:
 #0: ffff888027624358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1304

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x141/0x190 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
 watchdog+0xd25/0x1050 kernel/hung_task.c:515
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
 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: 0 Comm: swapper/0 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:test_states kernel/sched/psi.c:247 [inline]
RIP: 0010:psi_group_change+0x2e7/0xa20 kernel/sched/psi.c:861
Code: 48 89 f9 48 c1 e9 03 0f b6 14 11 84 d2 74 06 0f 8e b5 04 00 00 41 80 7e 08 00 0f 84 54 02 00 00 48 ba 00 00 00 00 00 fc ff df <4c> 89 f9 8b 1c 24 48 c1 e9 03 0f b6 0c 11 4c 89 fa c1 eb 08 83 e2
RSP: 0018:ffffc90000007d58 EFLAGS: 00000002
RAX: 0000000000000003 RBX: 00000000fffffffb RCX: 1ffffffff1cda3f9
RDX: dffffc0000000000 RSI: ffffffff8de50b8b RDI: ffffffff8e6d1fc8
RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000001
R10: dffffc0000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000002 R14: ffffffff8e6d1fc0 R15: ffff8880b8424680
FS:  0000000000000000(0000) GS:ffff888124342000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f81aff8 CR3: 0000000044007000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 psi_task_change+0x339/0x550 kernel/sched/psi.c:922
 psi_enqueue kernel/sched/stats.h:166 [inline]
 enqueue_task+0x1d6/0x4f0 kernel/sched/core.c:2109
 activate_task kernel/sched/core.c:2147 [inline]
 ttwu_do_activate+0x176/0x7c0 kernel/sched/core.c:3667
 sched_ttwu_pending+0x2b3/0x660 kernel/sched/core.c:3754
 csd_do_func kernel/smp.c:136 [inline]
 __flush_smp_call_function_queue+0x4d3/0x960 kernel/smp.c:593
 __sysvec_call_function_single+0x81/0x470 arch/x86/kernel/smp.c:271
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
 sysvec_call_function_single+0x9e/0xc0 arch/x86/kernel/smp.c:266
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:704
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 88 82 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d a3 71 1b 00 fb f4 <e9> fc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e407e00 EFLAGS: 00000242
RAX: 00000000047d2ab5 RBX: ffffffff8e4975c0 RCX: ffffffff8b901c75
RDX: 0000000000000000 RSI: ffffffff8de76c97 RDI: ffffffff8c1b06a0
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1017086795
R10: ffff8880b8433cab R11: 0000000000000000 R12: fffffbfff1c92eb8
R13: 0000000000000000 R14: ffffffff90d99110 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:767
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x43a/0x550 kernel/sched/idle.c:341
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:439
 rest_init+0x251/0x260 init/main.c:760
 start_kernel+0x47f/0x480 init/main.c:1210
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x148
 </TASK>