GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P10643/1:b..l..
rcu: (detected by 0, t=10503 jiffies, g=36737, q=959 ncpus=2)
task:syz.2.1253 state:R running task stack:25576 pid:10643 tgid:10643 ppid:5635 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7382
preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7662
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:543 [inline]
irqentry_exit+0x14f/0x9b0 kernel/entry/common.c:154
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x232/0x350 kernel/locking/lockdep.c:5947
Code: ff ff ff e8 e0 ea 50 0a f7 44 24 10 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 e2 d4 f7 12 48 3b 44 24 50 75 33 fb 48 83 c4 58 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 7f f2 53 0a cc 48 8d 3d c7 d4 db
RSP: 0018:ffffc900097af3e0 EFLAGS: 00000292
RAX: 818028b051ba9c00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000003b9a16c3 RSI: ffffffff8e7103d6 RDI: ffffffff8c6e1780
RBP: ffff888024745dc0 R08: ffffffff8178699f R09: 0000000000000000
R10: ffffc900097af518 R11: ffffffff81b301f0 R12: ffffffff8fd59ca0
R13: 0000000000000002 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
unwind_next_frame+0xac/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
save_stack+0x122/0x230 mm/page_owner.c:183
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:338
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962
tlb_batch_list_free mm/mmu_gather.c:161 [inline]
tlb_finish_mmu+0x13e/0x220 mm/mmu_gather.c:552
exit_mmap+0x4b2/0x9f0 mm/mmap.c:1328
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x18e/0x240 kernel/exit.c:586
do_exit+0x6a8/0x2360 kernel/exit.c:967
do_group_exit+0x22d/0x2f0 kernel/exit.c:1123
get_signal+0x1216/0x12c0 kernel/signal.c:3112
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__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:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fded419f559
RSP: 002b:00007fff409c45e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000000 RBX: 00000000000308a2 RCX: 00007fded419f559
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fded4425fac
RBP: 0000000000000032 R08: 3fffffffffffffff R09: 0000000000000000
R10: 00007fff409c46f0 R11: 0000000000000246 R12: 00007fff409c4710
R13: 00007fded4425fac R14: 00000000000308d4 R15: 00007fff409c46f0
rcu: rcu_preempt kthread starved for 904 jiffies! g36737 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27496 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x1230 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9c/0x340 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 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
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: 8230 Comm: kworker/u8:13 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Workqueue: wg-kex-wg2 wg_packet_handshake_send_worker
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:409 [inline]
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline]
RIP: 0010:unwind_next_frame+0xba7/0x2550 arch/x86/kernel/unwind_orc.c:614
Code: 00 fc ff df 48 8b 4c 24 10 0f b6 04 01 84 c0 0f 85 3b 14 00 00 41 83 3e 00 0f 95 c0 49 39 d7 0f 96 c1 20 c1 49 39 d5 0f 97 c0 <20> c8 3c 01 75 18 48 8d 42 08 4c 39 f8 0f 97 c1 4c 39 e8 0f 96 c0
RSP: 0018:ffffc90000a07b20 EFLAGS: 00000212
RAX: 0000000000000001 RBX: 1ffff92000140f7a RCX: 1ffff92000140f01
RDX: ffffc90000a08358 RSI: 0000000000000002 RDI: ffffc90000a07bd8
RBP: 1ffffffff253f8ce R08: ffffc90000a08360 R09: 0000000000000000
R10: ffffc90000a07c18 R11: ffffffff81b301f0 R12: 1ffff92000140f7b
R13: ffffc90000a09000 R14: ffffc90000a07bc8 R15: ffffc90000a01000
FS: 0000000000000000(0000) GS:ffff888123b6b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5e65df84b8 CR3: 0000000060c2a000 CR4: 00000000003526f0
Call Trace:
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
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:264 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6509 [inline]
kmem_cache_free+0x182/0x650 mm/slub.c:6636
kfree_skb_reason include/linux/skbuff.h:1329 [inline]
kfree_skb include/linux/skbuff.h:1338 [inline]
ip6_mc_input+0x878/0xc80 net/ipv6/ip6_input.c:639
ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:989
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:633
nf_hook include/linux/netfilter.h:280 [inline]
NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:323
__netif_receive_skb_one_core net/core/dev.c:6425 [inline]
__netif_receive_skb net/core/dev.c:6538 [inline]
netif_receive_skb_internal net/core/dev.c:6624 [inline]
netif_receive_skb+0x278/0xbf0 net/core/dev.c:6683
NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:325
br_handle_frame_finish+0x1219/0x1ae0 net/bridge/br_input.c:237
br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1
br_nf_pre_routing_finish_ipv6+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:325 [inline]
br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:293 [inline]
br_handle_frame+0x1329/0x1600 net/bridge/br_input.c:453
__netif_receive_skb_core+0x989/0x30f0 net/core/dev.c:6304
__netif_receive_skb_one_core net/core/dev.c:6423 [inline]
__netif_receive_skb net/core/dev.c:6538 [inline]
process_backlog+0x727/0x18b0 net/core/dev.c:6889
__napi_poll+0xaa/0x330 net/core/dev.c:7958
napi_poll net/core/dev.c:8021 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:8178
handle_softirqs+0x265/0x8d0 kernel/softirq.c:669
do_softirq+0x77/0xd0 kernel/softirq.c:569
__local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473
wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:36 [inline]
wg_packet_handshake_send_worker+0x1b2/0x370 drivers/net/wireguard/send.c:51
process_one_work kernel/workqueue.c:3495 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
kthread+0x38b/0x480 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