rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6911/1:b..l P6927/1:b..l P6921/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=27029, q=1001 ncpus=2)
task:syz.3.363       state:R  running task     stack:25592 pid:6921  tgid:6921  ppid:5631   task_flags:0x40004c flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7189
 preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7463
 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
 rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:753
 rcu_read_unlock include/linux/rcupdate.h:867 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
 unwind_next_frame+0x1b76/0x2550 arch/x86/kernel/unwind_orc.c:709
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5419
 kmalloc_noprof include/linux/slab.h:950 [inline]
 slab_free_hook mm/slub.c:2641 [inline]
 slab_free mm/slub.c:6250 [inline]
 kmem_cache_free+0x156/0x650 mm/slub.c:6377
 tear_down_vmas+0x312/0x520 mm/mmap.c:1262
 exit_mmap+0x4b6/0x9e0 mm/mmap.c:1320
 __mmput+0x118/0x430 kernel/fork.c:1178
 exit_mm+0x18e/0x250 kernel/exit.c:581
 do_exit+0x6a2/0x22c0 kernel/exit.c:963
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1117
 __do_sys_exit_group kernel/exit.c:1128 [inline]
 __se_sys_exit_group kernel/exit.c:1126 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1126
 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f206b59cdd9
RSP: 002b:00007fff668f1218 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f206b59cdd9
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff668f127c R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000049
R13: 00000000000927c0 R14: 0000000000029589 R15: 00007fff668f12d0
 </TASK>
task:syz.4.365       state:R  running task     stack:28760 pid:6927  tgid:6925  ppid:5629   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7189
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
 irqentry_exit+0x14f/0x730 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 51 f4 07 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 3b df 97 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d c8 89 92
RSP: 0018:ffffc900033df8d8 EFLAGS: 00000286
RAX: 90a6ede7d8c67b00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000005a44979c RSI: ffffffff8e21f27f RDI: ffffffff8c28ade0
RBP: ffffffff8176f256 R08: ffffffff8176f256 R09: ffffffff8e95cd60
R10: ffffc900033dfa38 R11: ffffffff81b0e910 R12: 0000000000000002
R13: ffffffff8e95cd60 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
 unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
 slab_free_hook mm/slub.c:2650 [inline]
 slab_free mm/slub.c:6250 [inline]
 kmem_cache_free+0x44f/0x650 mm/slub.c:6377
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
 exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3f1b99cdd9
RSP: 002b:00007f3f19bd5028 EFLAGS: 00000246 ORIG_RAX: 000000000000002b
RAX: ffffffffffffffea RBX: 00007f3f1bc16090 RCX: 00007f3f1b99cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f3f1ba32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3f1bc16128 R14: 00007f3f1bc16090 R15: 00007fff34edc518
 </TASK>
task:syz.2.360       state:R  running task     stack:23496 pid:6911  tgid:6910  ppid:5625   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7189
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
 irqentry_exit+0x14f/0x730 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 51 f4 07 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 3b df 97 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d c8 89 92
RSP: 0018:ffffc9000342e438 EFLAGS: 00000282
RAX: 2449126cf1c12f00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 00000000e01f7040 RSI: ffffffff8e21f27f RDI: ffffffff8c28ade0
RBP: ffffffff8176f256 R08: ffffffff8176f256 R09: ffffffff8e95cd60
R10: ffffc9000342e598 R11: ffffffff81b0e910 R12: 0000000000000002
R13: ffffffff8e95cd60 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
 unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5295 [inline]
 __kmalloc_node_track_caller_noprof+0x4db/0x7b0 mm/slub.c:5407
 kmalloc_reserve net/core/skbuff.c:635 [inline]
 pskb_expand_head+0x230/0x1390 net/core/skbuff.c:2302
 netlink_trim+0x1b3/0x2c0 net/netlink/af_netlink.c:1300
 netlink_broadcast_filtered+0x80/0xeb0 net/netlink/af_netlink.c:1513
 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
 nlmsg_multicast include/net/netlink.h:1184 [inline]
 nlmsg_notify+0xf0/0x1a0 net/netlink/af_netlink.c:2594
 netif_state_change+0x297/0x3a0 net/core/dev.c:1605
 do_setlink+0xc02/0x45a0 net/core/rtnetlink.c:3428
 rtnl_group_changelink net/core/rtnetlink.c:3814 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3982 [inline]
 rtnl_newlink+0x14ca/0x1bb0 net/core/rtnetlink.c:4110
 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6996
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2551
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1895
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
 __sys_sendmsg net/socket.c:2784 [inline]
 __do_sys_sendmsg net/socket.c:2789 [inline]
 __se_sys_sendmsg net/socket.c:2787 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb40959cdd9
RSP: 002b:00007fb40a53a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb409815fa0 RCX: 00007fb40959cdd9
RDX: 0000000000000000 RSI: 0000200000000140 RDI: 0000000000000009
RBP: 00007fb409632d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb409816038 R14: 00007fb409815fa0 R15: 00007ffd8a8c8f18
 </TASK>
rcu: rcu_preempt kthread starved for 5571 jiffies! g27029 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:26880 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7283
 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 50 Comm: kworker/u9:0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: hci2 hci_cmd_sync_work
RIP: 0010:__lock_acquire+0x2c5/0x2cf0 kernel/locking/lockdep.c:5171
Code: 00 48 89 6c 24 28 48 8d 04 ad 00 00 00 00 48 01 e8 89 f1 81 e1 ff 1f 00 00 ba 00 e0 ff ff 41 23 54 c7 20 09 ca 41 89 54 c7 20 <4d> 89 44 c7 08 4d 89 4c c7 10 48 8b 94 24 20 01 00 00 49 89 54 c7
RSP: 0018:ffffc90000007b80 EFLAGS: 00000006
RAX: 000000000000001e RBX: 0000000000000000 RCX: 0000000000000000
RDX: 00000000000c4000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000006 R08: ffffffff84bc95dc R09: ffffffff9a734f98
R10: ffff888011ea8308 R11: ffffed10023d5063 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88801bb9dc40 R15: ffff88801bb9e7d0
FS:  0000000000000000(0000) GS:ffff888125287000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3f19bd4ff8 CR3: 00000000630c0000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
 _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
 debug_object_deactivate+0x6c/0x3a0 lib/debugobjects.c:890
 debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1898 [inline]
 __hrtimer_run_queues+0x23a/0xa20 kernel/time/hrtimer.c:1994
 hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch+0x427/0xbe0 kernel/sched/core.c:5245
Code: 41 c7 84 24 e0 0d 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 d6 59 17 0a e8 11 f6 38 00 fb 49 8d bd a8 16 00 00 <48> 89 f8 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 7b 03 00 00 41 80
RSP: 0018:ffffc90000ba72b0 EFLAGS: 00000206
RAX: 00000000003dc3c9 RBX: 1ffff110170c7784 RCX: 0000000080000001
RDX: 0000000000000007 RSI: ffffffff8dfaab66 RDI: ffff88801bb9f2e8
RBP: ffffc90000ba7310 R08: ffffffff9030dcf7 R09: 1ffffffff2061b9e
R10: dffffc0000000000 R11: fffffbfff2061b9f R12: ffff8880b863ae88
R13: ffff88801bb9dc40 R14: ffff88803400dc40 R15: dffffc0000000000
 context_switch kernel/sched/core.c:5391 [inline]
 __schedule+0x17bc/0x5680 kernel/sched/core.c:7189
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7370
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
 _raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:198
 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline]
 __slab_free+0x222/0x2c0 mm/slub.c:-1
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4569 [inline]
 slab_alloc_node mm/slub.c:4898 [inline]
 kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4950
 __alloc_skb+0x1d0/0x7d0 net/core/skbuff.c:702
 alloc_skb include/linux/skbuff.h:1383 [inline]
 mgmt_alloc_skb net/bluetooth/mgmt_util.c:64 [inline]
 mgmt_send_event+0x46/0x190 net/bluetooth/mgmt_util.c:116
 mgmt_event net/bluetooth/mgmt.c:340 [inline]
 mgmt_connect_failed+0x322/0x4c0 net/bluetooth/mgmt.c:9911
 hci_conn_failed+0xda/0x340 net/bluetooth/hci_conn.c:1398
 hci_abort_conn_sync+0xdd0/0x1190 net/bluetooth/hci_sync.c:5763
 hci_cmd_sync_work+0x213/0x400 net/bluetooth/hci_sync.c:332
 process_one_work kernel/workqueue.c:3302 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>