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): P25273/1:b..l..
rcu: (detected by 0, t=10506 jiffies, g=123789, q=1125437 ncpus=2)
task:syz.2.5337 state:R running task stack:24368 pid:25273 tgid:25273 ppid:5642 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 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+0xd/0x350 kernel/locking/lockdep.c:5902
Code: c0 c3 cc cc cc cc cc 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 <53> 48 83 ec 58 4c 89 cb 45 89 c7 41 89 cd 89 54 24 04 41 89 f6 49
RSP: 0018:ffffc90004f37128 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff8240ac89 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9015a2a0
RBP: 1ffff920009e6e48 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90004f37258 R11: ffffffff81b3a390 R12: dffffc0000000000
R13: ffffffff817879cf R14: ffffc90004f37208 R15: 1ffff920009e6e41
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+0x73/0x2a0 mm/page_owner.c:338
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1403 [inline]
__free_frozen_pages+0xc97/0xd90 mm/page_alloc.c:2957
__slab_free+0x269/0x2c0 mm/slub.c:5926
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:361
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4720 [inline]
slab_alloc_node mm/slub.c:5033 [inline]
kmem_cache_alloc_noprof+0x2b4/0x600 mm/slub.c:5047
vm_area_dup+0x32/0x8e0 mm/vma_init.c:128
__split_vma+0x2db/0x8a0 mm/vma.c:549
split_vma mm/vma.c:633 [inline]
vma_modify+0xacf/0x25c0 mm/vma.c:1796
vma_modify_flags+0x2a4/0x3c0 mm/vma.c:1816
mprotect_fixup+0x54f/0xf20 mm/mprotect.c:823
do_mprotect_pkey+0x8e7/0xd40 mm/mprotect.c:1001
__do_sys_mprotect mm/mprotect.c:1022 [inline]
__se_sys_mprotect mm/mprotect.c:1019 [inline]
__x64_sys_mprotect+0x80/0x90 mm/mprotect.c:1019
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe225ba8d17
RSP: 002b:00007ffd7fb0ed18 EFLAGS: 00000206 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 00007fe223d936c0 RCX: 00007fe225ba8d17
RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007fe223d74000
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000021000 R11: 0000000000000206 R12: 00007ffd7fb0ee70
R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 1593 jiffies! g123789 f0x2 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/0x5830 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: 5377 Comm: crond Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
RIP: 0010:calc_global_load+0x0/0x3f0 kernel/sched/loadavg.c:352
Code: 86 d2 67 0a cc 48 c7 c7 a0 c7 01 90 48 89 de e8 56 8f 8c 03 e9 1c ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <0f> 1f 40 d6 41 57 41 56 41 54 53 49 be 00 00 00 00 00 fc ff df 4c
RSP: 0018:ffffc90000a07008 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 8000000001000703
RDX: 8000000001000701 RSI: ffffffff8e934b8c RDI: ffffffff8c8ea180
RBP: 0000000000000001 R08: 0000000001000101 R09: 0000000000000001
R10: dffffc0000000000 R11: fffff52000140df0 R12: 000000c17fa1d380
R13: ffff8880b8328ff8 R14: ffffffff81b9be8e R15: dffffc0000000000
FS: 00007f79505afc80(0000) GS:ffff888123509000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0e7bd11fe8 CR3: 0000000076076000 CR4: 00000000003526f0
Call Trace:
tick_do_update_jiffies64+0x25d/0x310 kernel/time/tick-sched.c:146
tick_sched_do_timer kernel/time/tick-sched.c:253 [inline]
tick_nohz_handler+0xee/0x6b0 kernel/time/tick-sched.c:310
__run_hrtimer kernel/time/hrtimer.c:2079 [inline]
__hrtimer_run_queues+0x371/0xa10 kernel/time/hrtimer.c:2136
hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2255
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:221
Code: f7 e8 3d 61 9c f5 f7 c3 00 02 00 00 74 05 e8 f0 02 c9 f5 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 74 55 8d f5 65 48 8b 05 ac 11 d9 08 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc90000a07418 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000282 RCX: 8000000000000702
RDX: 0000000000000003 RSI: ffffffff8e6a8733 RDI: 0000000000000001
RBP: ffff888050a49b50 R08: ffffffff91bdfcbf R09: 1ffffffff237bf97
R10: dffffc0000000000 R11: fffffbfff237bf98 R12: 0000000000000000
R13: ffff888152ba4000 R14: ffffffff9c09aea8 R15: 0000000000000000
__debug_check_no_obj_freed lib/debugobjects.c:1180 [inline]
debug_check_no_obj_freed+0x39e/0x450 lib/debugobjects.c:1201
slab_free_hook mm/slub.c:2711 [inline]
slab_free mm/slub.c:6630 [inline]
kfree+0x13e/0x650 mm/slub.c:6923
skb_release_all net/core/skbuff.c:1188 [inline]
__kfree_skb+0x5d/0x210 net/core/skbuff.c:1202
kfree_skb_reason include/linux/skbuff.h:1329 [inline]
enqueue_to_backlog+0x68c/0xef0 net/core/dev.c:5642
netif_rx_internal+0x120/0x550 net/core/dev.c:5944
__netif_rx+0x7e/0xd0 net/core/dev.c:5964
loopback_xmit+0x48f/0x760 drivers/net/loopback.c:96
__netdev_start_xmit include/linux/netdevice.h:5457 [inline]
netdev_start_xmit include/linux/netdevice.h:5466 [inline]
xmit_one net/core/dev.c:4068 [inline]
dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:4084
sch_direct_xmit+0x257/0x4c0 net/sched/sch_generic.c:411
qdisc_restart net/sched/sch_generic.c:476 [inline]
__qdisc_run+0xe33/0x1b30 net/sched/sch_generic.c:484
qdisc_run include/net/pkt_sched.h:121 [inline]
__dev_xmit_skb net/core/dev.c:4490 [inline]
__dev_queue_xmit+0x1c2c/0x3920 net/core/dev.c:5046
dev_queue_xmit include/linux/netdevice.h:3485 [inline]
neigh_hh_output include/net/neighbour.h:538 [inline]
neigh_output include/net/neighbour.h:552 [inline]
ip_finish_output2+0xcd0/0x1150 net/ipv4/ip_output.c:236
NF_HOOK_COND include/linux/netfilter.h:314 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:437
nf_dup_ipv4+0x6ab/0x900 net/ipv4/netfilter/nf_dup_ipv4.c:90
tee_tg4+0xe7/0x140 net/netfilter/xt_TEE.c:42
ipt_do_table+0xce5/0x15d0 net/ipv4/netfilter/ip_tables.c:345
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:633
nf_hook+0x22a/0x3a0 include/linux/netfilter.h:280
__ip_local_out+0x558/0x6a0 net/ipv4/ip_output.c:120
ip_local_out+0x2a/0x190 net/ipv4/ip_output.c:129
synproxy_send_client_synack+0x89b/0xde0 net/netfilter/nf_synproxy_core.c:487
nft_synproxy_eval_v4+0x362/0x4e0 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x389/0x5d0 net/netfilter/nft_synproxy.c:142
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x48d/0x1b10 net/netfilter/nf_tables_core.c:285
nft_do_chain_ipv4+0x195/0x290 net/netfilter/nft_chain_filter.c:24
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
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325
__netif_receive_skb_one_core net/core/dev.c:6435 [inline]
__netif_receive_skb net/core/dev.c:6548 [inline]
process_backlog+0xa6b/0x18b0 net/core/dev.c:6899
__napi_poll+0xaa/0x330 net/core/dev.c:7985
napi_poll net/core/dev.c:8048 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:8205
handle_softirqs+0x265/0x8d0 kernel/softirq.c:669
__do_softirq kernel/softirq.c:703 [inline]
invoke_softirq kernel/softirq.c:542 [inline]
__irq_exit_rcu+0xc6/0x220 kernel/softirq.c:786
irq_exit_rcu+0x9/0x30 kernel/softirq.c:809
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:221
Code: f7 e8 3d 61 9c f5 f7 c3 00 02 00 00 74 05 e8 f0 02 c9 f5 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 74 55 8d f5 65 48 8b 05 ac 11 d9 08 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc900036e7748 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000296 RCX: 8000000000000001
RDX: 0000000000000007 RSI: ffffffff8e6a8733 RDI: 0000000000000001
RBP: ffff888027f992b0 R08: ffffffff91bdfcbf R09: 1ffffffff237bf97
R10: dffffc0000000000 R11: fffffbfff237bf98 R12: 000000000000012c
R13: ffff88804848c000 R14: ffffffff9c150450 R15: 0000000000000000
__debug_check_no_obj_freed lib/debugobjects.c:1180 [inline]
debug_check_no_obj_freed+0x39e/0x450 lib/debugobjects.c:1201
__free_pages_prepare mm/page_alloc.c:1410 [inline]
__free_frozen_pages+0x5cc/0xd90 mm/page_alloc.c:2957
__slab_free+0x269/0x2c0 mm/slub.c:5926
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:361
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4720 [inline]
slab_alloc_node mm/slub.c:5033 [inline]
kmem_cache_alloc_noprof+0x2b4/0x600 mm/slub.c:5047
lsm_file_alloc security/security.c:172 [inline]
security_file_alloc+0x34/0x310 security/security.c:2428
init_file+0x90/0x2b0 fs/file_table.c:184
alloc_empty_file+0x74/0x1d0 fs/file_table.c:266
path_openat+0x96/0x20f0 fs/namei.c:5002
do_file_open+0x23e/0x4a0 fs/namei.c:5045
do_sys_openat2+0x115/0x200 fs/open.c:1442
do_sys_open fs/open.c:1448 [inline]
__do_sys_openat fs/open.c:1464 [inline]
__se_sys_openat fs/open.c:1459 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1459
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f79506ff407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffe18376f20 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f79505afc80 RCX: 00007f79506ff407
RDX: 0000000000000000 RSI: 00007f79508f2764 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007f79508fe492
R13: 00007f79508fe492 R14: 0000000000000001 R15: 0000000000000032