rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P974/1:b..l P5824/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=65897, q=973432 ncpus=2)
task:kworker/0:3 state:R running task stack:23208 pid:5824 tgid:5824 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090
irqentry_exit+0x36/0x90 kernel/entry/common.c:354
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:unwind_next_frame+0x674/0x20a0 arch/x86/kernel/unwind_orc.c:581
Code: 85 a4 15 00 00 83 e0 07 38 c2 40 0f 9e c6 84 d2 0f 95 c0 40 84 c6 0f 85 8d 15 00 00 4c 0f bf 31 4d 01 fe 0f b6 41 05 83 e0 07 <3c> 03 0f 84 bd 08 00 00 3c 04 0f 84 f6 07 00 00 3c 02 0f 84 cd 04
RSP: 0018:ffffc900015e6930 EFLAGS: 00000202
RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff91268dcc
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffc900015e69e8 R08: ffffffff91268dd0 R09: 0000000000000000
R10: 0000000000000006 R11: 000000000001164e R12: ffffc900015e69f0
R13: ffffc900015e69a0 R14: ffffc900015e6dc8 R15: ffffc900015e6db8
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1262 [inline]
__free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2725
discard_slab mm/slub.c:2716 [inline]
__put_partials+0x16d/0x1c0 mm/slub.c:3185
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4147 [inline]
slab_alloc_node mm/slub.c:4196 [inline]
__do_kmalloc_node mm/slub.c:4326 [inline]
__kmalloc_noprof+0x1d4/0x510 mm/slub.c:4339
kmalloc_noprof include/linux/slab.h:909 [inline]
usb_alloc_urb+0x66/0xa0 drivers/usb/core/urb.c:75
usb_internal_control_msg drivers/usb/core/message.c:96 [inline]
usb_control_msg+0x1d3/0x4a0 drivers/usb/core/message.c:154
hid_get_class_descriptor.constprop.0+0x9a/0xf0 drivers/hid/usbhid/hid-core.c:672
usbhid_parse+0x6ab/0xa60 drivers/hid/usbhid/hid-core.c:1040
hid_add_device+0x18a/0xa60 drivers/hid/hid-core.c:2874
usbhid_probe+0xd38/0x13f0 drivers/hid/usbhid/hid-core.c:1432
usb_probe_interface+0x300/0x9c0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:657
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1a70 drivers/base/core.c:3692
usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:579 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:657
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
__device_attach_driver+0x1df/0x310 drivers/base/dd.c:957
bus_for_each_drv+0x156/0x1e0 drivers/base/bus.c:462
__device_attach+0x1e4/0x4b0 drivers/base/dd.c:1029
bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
device_add+0x1148/0x1a70 drivers/base/core.c:3692
usb_new_device+0xd07/0x1a20 drivers/usb/core/hub.c:2663
hub_port_connect drivers/usb/core/hub.c:5531 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
port_event drivers/usb/core/hub.c:5831 [inline]
hub_event+0x2eb7/0x4fa0 drivers/usb/core/hub.c:5913
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:kworker/0:2 state:R running task stack:22824 pid:974 tgid:974 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090
irqentry_exit+0x36/0x90 kernel/entry/common.c:354
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5870
Code: fe 0b 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 42 f2 ec 0e 0f 82 74 02 00 00 8b 35 da 21 ed 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 19 fe 0b 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc9000383efe8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3bf5c0 RCX: 00000000e725ccd1
RDX: 0000000000000000 RSI: ffffffff8dbbbc4f RDI: ffffffff8bf482a0
RBP: 0000000000000002 R08: 5092ae54d075f504 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
save_stack+0x160/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1262 [inline]
__free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2725
discard_slab mm/slub.c:2716 [inline]
__put_partials+0x16d/0x1c0 mm/slub.c:3185
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4147 [inline]
slab_alloc_node mm/slub.c:4196 [inline]
__kmalloc_cache_noprof+0x1f1/0x3e0 mm/slub.c:4353
kmalloc_noprof include/linux/slab.h:905 [inline]
dummy_urb_enqueue+0xa3/0x920 drivers/usb/gadget/udc/dummy_hcd.c:1273
usb_hcd_submit_urb+0x258/0x1c60 drivers/usb/core/hcd.c:1533
usb_submit_urb+0x87c/0x1730 drivers/usb/core/urb.c:581
usb_start_wait_urb+0x104/0x4b0 drivers/usb/core/message.c:59
usb_internal_control_msg drivers/usb/core/message.c:103 [inline]
usb_control_msg+0x326/0x4a0 drivers/usb/core/message.c:154
usb_get_string+0xab/0x1a0 drivers/usb/core/message.c:844
usb_string_sub+0x8e/0x390 drivers/usb/core/message.c:888
usb_get_langid drivers/usb/core/message.c:920 [inline]
usb_string+0x1d6/0x670 drivers/usb/core/message.c:984
usb_cache_string+0x80/0x150 drivers/usb/core/message.c:1030
usb_enumerate_device drivers/usb/core/hub.c:2505 [inline]
usb_new_device+0x169/0x1a20 drivers/usb/core/hub.c:2633
hub_port_connect drivers/usb/core/hub.c:5531 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5671 [inline]
port_event drivers/usb/core/hub.c:5831 [inline]
hub_event+0x2eb7/0x4fa0 drivers/usb/core/hub.c:5913
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 4632 jiffies! g65897 f0x2 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:27704 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.15.0-rc5-syzkaller-00032-g0d8d44db295c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x4b/0xc0 kernel/rcu/tree.c:736
Code: 00 00 00 48 8d 3c ed 00 cd ce 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 5c 48 03 1c ed 00 cd ce 8d <48> b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 0f b6 14 02 48
RSP: 0018:ffffc90000006d48 EFLAGS: 00000287
RAX: dffffc0000000000 RBX: ffff8880b8432de8 RCX: ffffffff8a1caf6a
RDX: 1ffffffff1b9d9a0 RSI: ffffffff8bf48220 RDI: ffffffff8dcecd00
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88805fb738cf
R13: ffff88805fb738b8 R14: 1ffff92000000dbc R15: ffff888054a0a000
FS: 0000000000000000(0000) GS:ffff8881249df000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f25ec000000 CR3: 0000000073bfd000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_lock_held_common kernel/rcu/update.c:109 [inline]
rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349
__in6_dev_get include/net/addrconf.h:347 [inline]
ip6_ignore_linkdown include/net/addrconf.h:443 [inline]
find_match+0x373/0x15d0 net/ipv6/route.c:781
__find_rr_leaf+0x140/0xe00 net/ipv6/route.c:869
find_rr_leaf net/ipv6/route.c:890 [inline]
rt6_select net/ipv6/route.c:934 [inline]
fib6_table_lookup+0x57c/0xa30 net/ipv6/route.c:2230
ip6_pol_route+0x1cc/0x1230 net/ipv6/route.c:2266
pol_lookup_func include/net/ip6_fib.h:616 [inline]
fib6_rule_lookup+0x24c/0x720 net/ipv6/fib6_rules.c:120
ip6_route_output_flags_noref net/ipv6/route.c:2674 [inline]
ip6_route_output_flags+0x1d0/0x640 net/ipv6/route.c:2686
ip6_route_output include/net/ip6_route.h:93 [inline]
__nf_ip6_route+0x4c/0xe0 net/ipv6/netfilter.c:113
nf_ip6_route include/linux/netfilter_ipv6.h:111 [inline]
synproxy_send_tcp_ipv6+0x365/0x680 net/netfilter/nf_synproxy_core.c:835
synproxy_send_client_synack_ipv6+0x635/0x7e0 net/netfilter/nf_synproxy_core.c:897
nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:90 [inline]
nft_synproxy_do_eval+0x93b/0xd80 net/netfilter/nft_synproxy.c:145
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e6/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x18a/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626
nf_hook.constprop.0+0x422/0x750 include/linux/netfilter.h:269
NF_HOOK include/linux/netfilter.h:312 [inline]
ip6_input+0xe0/0x2f0 net/ipv6/ip6_input.c:491
dst_input include/net/dst.h:469 [inline]
ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
NF_HOOK include/linux/netfilter.h:314 [inline]
NF_HOOK include/linux/netfilter.h:308 [inline]
ipv6_rcv+0x265/0x680 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5887
__netif_receive_skb+0x1d/0x160 net/core/dev.c:6000
process_backlog+0x442/0x15e0 net/core/dev.c:6352
__napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7324
napi_poll net/core/dev.c:7388 [inline]
net_rx_action+0xa97/0x1010 net/core/dev.c:7510
handle_softirqs+0x216/0x8e0 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:81
Code: 15 62 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 73 1a 1d 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e007e10 EFLAGS: 000002c6
RAX: 0000000003a467e5 RBX: 0000000000000000 RCX: ffffffff8b6cd419
RDX: 0000000000000000 RSI: ffffffff8dbe123f RDI: ffffffff8bf482a0
RBP: fffffbfff1c12ee8 R08: 0000000000000001 R09: ffffed10170865bd
R10: ffff8880b8432deb R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff8e097740 R14: ffffffff90850410 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:748
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423
rest_init+0x16b/0x2b0 init/main.c:743
start_kernel+0x3e9/0x4d0 init/main.c:1099
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:513
x86_64_start_kernel+0xb0/0xc0 arch/x86/kernel/head64.c:494
common_startup_64+0x13e/0x148