rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29230/1:b..l P31395/1:b..l P25489/1:b..l P5814/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=270157, q=471 ncpus=2)
task:syz-executor state:R running task stack:23704 pid:5814 tgid:5814 ppid:5813 task_flags:0x400100 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5dd0 kernel/sched/core.c:6786
preempt_schedule_notrace+0x62/0xe0 kernel/sched/core.c:7059
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x8e/0xc0 kernel/rcu/tree.c:746
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x201/0x2f0 kernel/locking/lockdep.c:5882
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
__update_page_owner_free_handle.constprop.0+0x31b/0x4a0 mm/page_owner.c:283
__reset_page_owner+0x93/0x1a0 mm/page_owner.c:309
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
__free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
discard_slab mm/slub.c:2717 [inline]
__put_partials+0x16d/0x1c0 mm/slub.c:3186
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
__kasan_kmalloc+0x8a/0xb0 mm/kasan/common.c:385
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4328 [inline]
__kmalloc_noprof+0x223/0x510 mm/slub.c:4340
kmalloc_noprof include/linux/slab.h:909 [inline]
kmalloc_array_noprof include/linux/slab.h:948 [inline]
alloc_pipe_info+0x1ec/0x590 fs/pipe.c:815
get_pipe_inode fs/pipe.c:894 [inline]
create_pipe_files+0x8c/0x9a0 fs/pipe.c:926
__do_pipe_flags fs/pipe.c:988 [inline]
do_pipe2+0xaf/0x1c0 fs/pipe.c:1036
__do_sys_pipe2 fs/pipe.c:1054 [inline]
__se_sys_pipe2 fs/pipe.c:1052 [inline]
__x64_sys_pipe2+0x54/0x80 fs/pipe.c:1052
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f334bb8d6c9
RSP: 002b:00007ffc877bab68 EFLAGS: 00000246 ORIG_RAX: 0000000000000125
RAX: ffffffffffffffda RBX: 000055556fcf1dc0 RCX: 00007f334bb8d6c9
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00007ffc877bab78
RBP: 00007ffc877baf30 R08: 0000000000000007 R09: 000055556fd8f410
R10: 50873d832c84ea76 R11: 0000000000000246 R12: 000055556fceead0
R13: 000055556fcf35a8 R14: 00007ffc877bacb0 R15: 000055556fcf8488
task:kworker/u8:1 state:R running task stack:21752 pid:25489 tgid:25489 ppid:2 task_flags:0x24248060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5dd0 kernel/sched/core.c:6786
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109
irqentry_exit+0x36/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5896
Code: 0f c1 05 48 1d 3a 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 5d db 39 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc9000c2b6d08 EFLAGS: 00000206
RAX: 35f661dea21bad00 RBX: ffffffff8e5c4e00 RCX: ffffc9000c2b6d14
RDX: 0000000000000005 RSI: ffffffff8de10c2d RDI: ffffffff8c15bf60
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000014330 R12: ffffffff816aeac4
R13: 0000000000000206 R14: ffff888029c74880 R15: 0000000000000006
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0x3f9/0x20a0 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:1248 [inline]
__free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
discard_slab mm/slub.c:2717 [inline]
__put_partials+0x16d/0x1c0 mm/slub.c:3186
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x4d/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:4148 [inline]
slab_alloc_node mm/slub.c:4197 [inline]
kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
ext4_init_io_end+0x24/0x170 fs/ext4/page-io.c:307
ext4_do_writepages+0x985/0x3490 fs/ext4/inode.c:2809
ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:2951
do_writepages+0x27a/0x600 mm/page-writeback.c:2636
__writeback_single_inode+0x160/0xfb0 fs/fs-writeback.c:1680
writeback_sb_inodes+0x601/0xf90 fs/fs-writeback.c:1976
__writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2047
wb_writeback+0x7f3/0xb70 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0x8ca/0xbe0 fs/fs-writeback.c:2343
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz.4.6804 state:R running task stack:27128 pid:31395 tgid:31394 ppid:25374 task_flags:0x40044c flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5dd0 kernel/sched/core.c:6786
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109
irqentry_exit+0x36/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875
Code: d6 39 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 32 c7 10 0f 0f 82 74 02 00 00 8b 35 1a f9 10 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 c9 d5 39 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc9000366f368 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c4e00 RCX: 00000000d07dbe9a
RDX: 0000000000000000 RSI: ffffffff8de10c2d RDI: ffffffff8c15bf60
RBP: 0000000000000002 R08: 6eb3b28d7bd48ca4 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 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:1248 [inline]
__free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
discard_slab mm/slub.c:2717 [inline]
__put_partials+0x16d/0x1c0 mm/slub.c:3186
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x4d/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:4148 [inline]
slab_alloc_node mm/slub.c:4197 [inline]
__do_kmalloc_node mm/slub.c:4327 [inline]
__kmalloc_node_track_caller_noprof+0x1d3/0x510 mm/slub.c:4347
kvasprintf+0xbc/0x160 lib/kasprintf.c:25
kasprintf+0xc7/0x100 lib/kasprintf.c:59
make_driver_name drivers/base/module.c:16 [inline]
module_remove_driver+0x136/0x250 drivers/base/module.c:108
bus_remove_driver+0x143/0x2c0 drivers/base/bus.c:748
driver_unregister+0x76/0xb0 drivers/base/driver.c:277
usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1732
raw_release+0x1ae/0x2b0 drivers/usb/gadget/legacy/raw_gadget.c:462
__fput+0x402/0xb70 fs/file_table.c:468
task_work_run+0x14d/0x240 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x86c/0x2bd0 kernel/exit.c:964
do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa0b938e5ab
RSP: 002b:00007fa0ba1b1f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007fa0b938e5ab
RDX: 00007fa0ba1b2fe0 RSI: 0000000041015500 RDI: 0000000000000005
RBP: 00007fa0ba1b2fe0 R08: 0000000000000000 R09: 00342e6364755f79
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007fa0ba1b1fb0 R14: 0000200000000140 R15: 00007fa0b96e13f0
task:kworker/1:4 state:R running task stack:22344 pid:29230 tgid:29230 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5dd0 kernel/sched/core.c:6786
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109
irqentry_exit+0x36/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5896
Code: 0f c1 05 48 1d 3a 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 5d db 39 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41
RSP: 0018:ffffc900053ef208 EFLAGS: 00000206
RAX: d62aac8302521f00 RBX: ffffffff8e5c4e00 RCX: ffffc900053ef214
RDX: 0000000000000005 RSI: ffffffff8de10c2d RDI: ffffffff8c15bf60
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff822b6406
R13: 0000000000000206 R14: ffff88802db28000 R15: 0000000000000006
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
__update_page_owner_free_handle.constprop.0+0x31b/0x4a0 mm/page_owner.c:283
__reset_page_owner+0x93/0x1a0 mm/page_owner.c:309
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
__free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
discard_slab mm/slub.c:2717 [inline]
__put_partials+0x16d/0x1c0 mm/slub.c:3186
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
__kasan_kmalloc+0x8a/0xb0 mm/kasan/common.c:385
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4328 [inline]
__kmalloc_noprof+0x223/0x510 mm/slub.c:4340
kmalloc_noprof include/linux/slab.h:909 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
kobject_get_path+0xd2/0x2a0 lib/kobject.c:161
kobject_uevent_env+0x289/0x1870 lib/kobject_uevent.c:545
driver_bound+0x164/0x230 drivers/base/dd.c:421
really_probe+0x62b/0xa90 drivers/base/dd.c:707
__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+0x159/0x1e0 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:2694
hub_port_connect drivers/usb/core/hub.c:5566 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x2f34/0x4fe0 drivers/usb/core/hub.c:5952
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 9610 jiffies! g270157 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:26584 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x116a/0x5dd0 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6879
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6941 Comm: kworker/u8:40 Not tainted 6.16.0-syzkaller-00857-gced1b9e0392d #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker
RIP: 0010:nf_nat_ipv6_in+0x163/0x340 net/netfilter/nf_nat_proto.c:1007
Code: fe 48 89 54 24 38 4c 89 ea 48 89 44 24 30 e8 04 d3 ff ff 31 ff 41 89 c5 41 89 c4 41 81 e5 fd 00 00 00 44 89 ee e8 cd 8a 01 f8 <45> 85 ed 0f 84 ae 00 00 00 e8 7f 8f 01 f8 48 8b 54 24 08 48 b8 00
RSP: 0018:ffffc90000a089a0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff92000141136 RCX: ffffffff89ba6993
RDX: ffff888025e88000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffffc90000a08a40 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff8882313f70b8 R12: 0000000000000001
R13: 0000000000000001 R14: ffff8882313f70b8 R15: ffff8882313f7000
FS: 0000000000000000(0000) GS:ffff8881247f9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3347bde640 CR3: 0000000074b26000 CR4: 00000000003526f0
Call Trace:
nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline]
nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
nf_hook.constprop.0+0x422/0x750 include/linux/netfilter.h:272
NF_HOOK include/linux/netfilter.h:315 [inline]
ipv6_rcv+0xa4/0x680 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:5977
__netif_receive_skb+0x1d/0x160 net/core/dev.c:6090
process_backlog+0x442/0x15e0 net/core/dev.c:6442
__napi_poll.constprop.0+0xba/0x550 net/core/dev.c:7414
napi_poll net/core/dev.c:7478 [inline]
net_rx_action+0xa9f/0xfe0 net/core/dev.c:7605
handle_softirqs+0x219/0x8e0 kernel/softirq.c:579
do_softirq kernel/softirq.c:480 [inline]
do_softirq+0xb2/0xf0 kernel/softirq.c:467
__local_bh_enable_ip+0x100/0x120 kernel/softirq.c:407
local_bh_enable include/linux/bottom_half.h:33 [inline]
fpregs_unlock arch/x86/include/asm/fpu/api.h:77 [inline]
kernel_fpu_end+0x5e/0x70 arch/x86/kernel/fpu/core.c:476
blake2s_compress+0x7f/0xe0 arch/x86/lib/crypto/blake2s-glue.c:46
blake2s_update+0xef/0x360 lib/crypto/blake2s.c:32
hmac.constprop.0+0x32a/0x420 drivers/net/wireguard/noise.c:332
kdf.constprop.0+0x122/0x280 drivers/net/wireguard/noise.c:360
mix_dh+0xe8/0x150 drivers/net/wireguard/noise.c:413
wg_noise_handshake_create_initiation+0x2e1/0x650 drivers/net/wireguard/noise.c:550
wg_packet_send_handshake_initiation+0x19a/0x360 drivers/net/wireguard/send.c:34
wg_packet_handshake_send_worker+0x1c/0x30 drivers/net/wireguard/send.c:51
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3321 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
kthread+0x3c5/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245