rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6694/1:b..l P7073/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=13901, q=434 ncpus=2)
task:dhcpcd-run-hook state:R running task stack:27496 pid:7073 tgid:7073 ppid:7042 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_notrace+0x62/0xe0 kernel/sched/core.c:7140
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:752
rcu_read_unlock include/linux/rcupdate.h:895 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xa3b/0x20b0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
slab_free_hook mm/slub.c:2501 [inline]
slab_free mm/slub.c:6670 [inline]
kmem_cache_free+0x15e/0x770 mm/slub.c:6781
exit_mmap+0x507/0xb60 mm/mmap.c:1302
__mmput+0x12a/0x410 kernel/fork.c:1173
mmput+0x62/0x70 kernel/fork.c:1196
exec_mmap fs/exec.c:901 [inline]
begin_new_exec+0x1280/0x3770 fs/exec.c:1156
load_elf_binary+0x8e7/0x4fe0 fs/binfmt_elf.c:1010
search_binary_handler fs/exec.c:1669 [inline]
exec_binprm fs/exec.c:1701 [inline]
bprm_execve fs/exec.c:1753 [inline]
bprm_execve+0x8c2/0x1620 fs/exec.c:1729
do_execveat_common.isra.0+0x4a5/0x610 fs/exec.c:1859
do_execve fs/exec.c:1933 [inline]
__do_sys_execve fs/exec.c:2009 [inline]
__se_sys_execve fs/exec.c:2004 [inline]
__x64_sys_execve+0x8e/0xb0 fs/exec.c:2004
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0e5ef49107
RSP: 002b:00007ffe5bdac598 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 0000561814d50e88 RCX: 00007f0e5ef49107
RDX: 0000561814d50ea8 RSI: 0000561814d50e88 RDI: 0000561814d50f30
RBP: 0000561814d50f30 R08: 00007ffe5bdb0eb0 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000561814d50ea8
R13: 00007f0e5f10ee8b R14: 0000561814d50ea8 R15: 0000000000000000
task:kworker/0:12 state:R running task stack:20568 pid:6694 tgid:6694 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x62/0x330 kernel/locking/lockdep.c:5872
Code: b4 18 12 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 72 b9 ee 0e 0f 82 74 02 00 00 8b 35 0a ea ee 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 89 b4 18 12 0f 85 ad 02 00 00 48 83 c4
RSP: 0018:ffffc9000487e190 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c96a0 RCX: 000000007e0a2e13
RDX: 0000000000000000 RSI: ffffffff8daa7ea1 RDI: ffffffff8bf2b400
RBP: 0000000000000002 R08: 000000003ab82069 R09: 0000000093ab8206
R10: 0000000000000002 R11: ffff88803490d4b0 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd1/0x20b0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
kasan_save_track+0x14/0x30 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:414
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
snd_seq_create_port+0xf7/0xae0 sound/core/seq/seq_ports.c:132
snd_seq_ioctl_create_port+0x253/0x950 sound/core/seq/seq_clientmgr.c:1289
call_seq_client_ctl+0xa3/0x130 sound/core/seq/seq_clientmgr.c:2418
snd_seq_kernel_client_ctl+0x7a/0xc0 sound/core/seq/seq_clientmgr.c:2446
snd_seq_midisynth_probe+0x638/0x15f0 sound/core/seq/seq_midi.c:388
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x241/0xb20 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x470 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x350 drivers/base/dd.c:959
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031
device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086
bus_probe_device+0x64/0x150 drivers/base/bus.c:574
device_add+0x116e/0x1980 drivers/base/core.c:3689
snd_seq_device_dev_register+0x3d/0xf0 sound/core/seq_device.c:170
__snd_device_register sound/core/device.c:149 [inline]
snd_device_register+0x156/0x1f0 sound/core/device.c:179
snd_rawmidi_dev_register+0x972/0x1280 sound/core/rawmidi.c:2036
__snd_device_register sound/core/device.c:149 [inline]
snd_device_register_all+0x10f/0x1b0 sound/core/device.c:197
snd_card_register+0x106/0x7c0 sound/core/init.c:893
try_to_register_card+0x1d6/0x3a0 sound/usb/card.c:902
usb_audio_probe+0xb6b/0x3ea0 sound/usb/card.c:1045
usb_probe_interface+0x303/0xa80 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x241/0xb20 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x470 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x350 drivers/base/dd.c:959
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031
device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086
bus_probe_device+0x64/0x150 drivers/base/bus.c:574
device_add+0x116e/0x1980 drivers/base/core.c:3689
usb_set_configuration+0x1187/0x1e50 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:581 [inline]
really_probe+0x241/0xb20 drivers/base/dd.c:659
__driver_probe_device+0x1de/0x470 drivers/base/dd.c:801
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
__device_attach_driver+0x1df/0x350 drivers/base/dd.c:959
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031
device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086
bus_probe_device+0x64/0x150 drivers/base/bus.c:574
device_add+0x116e/0x1980 drivers/base/core.c:3689
usb_new_device+0xd07/0x1a90 drivers/usb/core/hub.c:2695
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x313a/0x52f0 drivers/usb/core/hub.c:5953
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 10638 jiffies! g13901 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:28584 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
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 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: c6 5f 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 13 49 12 00 fb f4 cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007df8 EFLAGS: 000002c6
RAX: 00000000004d9881 RBX: 0000000000000000 RCX: ffffffff8b7816d9
RDX: 0000000000000000 RSI: ffffffff8dacdf23 RDI: ffffffff8bf2b400
RBP: fffffbfff1c12f68 R08: 0000000000000001 R09: ffffed101708673d
R10: ffff8880b84339eb R11: ffffffff8e098670 R12: 0000000000000000
R13: ffffffff8e097b40 R14: ffffffff9088b4d0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881248f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555871b74a8 CR3: 000000004f718000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 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+0x38d/0x510 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
rest_init+0x16b/0x2b0 init/main.c:757
start_kernel+0x3ef/0x4d0 init/main.c:1206
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x148