syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4674/1:b..l P4887/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=16585, q=3569101 ncpus=2)
task:dhcpcd          state:R  running task     stack:25840 pid:4887  tgid:4887  ppid:1      flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5322 [inline]
 __schedule+0xef5/0x5750 kernel/sched/core.c:6682
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6861
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 unwind_next_frame+0x1776/0x20c0 arch/x86/kernel/unwind_orc.c:672
 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 save_stack+0x162/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x8d/0x400 mm/page_owner.c:297
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0x5f4/0xdc0 mm/page_alloc.c:2638
 __put_partials+0x14c/0x170 mm/slub.c:3145
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_node_noprof+0x153/0x310 mm/slub.c:4186
 __alloc_skb+0x2b1/0x380 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1322 [inline]
 alloc_skb_with_frags+0xe4/0x850 net/core/skbuff.c:6612
 sock_alloc_send_pskb+0x7f1/0x980 net/core/sock.c:2883
 unix_dgram_sendmsg+0x4b8/0x19e0 net/unix/af_unix.c:2027
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg net/socket.c:744 [inline]
 sock_write_iter+0x4fe/0x5b0 net/socket.c:1165
 do_iter_readv_writev+0x532/0x7f0 fs/read_write.c:834
 vfs_writev+0x363/0xdd0 fs/read_write.c:1064
 do_writev+0x289/0x370 fs/read_write.c:1111
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55c3f61e03
RSP: 002b:00007ffd1bdf70a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007ffd1bdf73e8 RCX: 00007f55c3f61e03
RDX: 0000000000000005 RSI: 00007ffd1bdf70c0 RDI: 000000000000000a
RBP: 0000000000004801 R08: 000000000000000a R09: 00007ffd1bdf7100
R10: 00007ffd1bdf7108 R11: 0000000000000246 R12: 000055c9f8018140
R13: 000055c9cdce0f88 R14: 00000000ffffffff R15: 000055c9f8025b20
 </TASK>
task:udevd           state:R  running task     stack:24224 pid:4674  tgid:4674  ppid:1      flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5322 [inline]
 __schedule+0xef5/0x5750 kernel/sched/core.c:6682
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7004
 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:__update_page_owner_free_handle mm/page_owner.c:273 [inline]
RIP: 0010:__reset_page_owner+0x100/0x400 mm/page_owner.c:298
Code: 31 ff 44 89 e6 e8 20 be 94 ff 49 01 ef 45 85 e4 74 4a e8 d3 bb 94 ff be 08 00 00 00 48 89 ef e8 e6 42 f6 ff 48 0f ba 75 00 01 <49> 8d 7f 0c 48 b8 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f
RSP: 0018:ffffc9000322fb18 EFLAGS: 00000247
RAX: 0000000000000001 RBX: 0000000000000007 RCX: ffffffff81f8c79a
RDX: ffffed1003c87347 RSI: 0000000000000008 RDI: ffff88801e439a30
RBP: ffff88801e439a30 R08: 0000000000000001 R09: ffffed1003c87346
R10: ffff88801e439a37 R11: 0000000000000000 R12: 00000000039401c0
R13: 0000000000000008 R14: 0000000000000003 R15: ffff88801e439a38
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0x5f4/0xdc0 mm/page_alloc.c:2638
 __put_partials+0x14c/0x170 mm/slub.c:3145
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 __kmalloc_cache_noprof+0x11e/0x300 mm/slub.c:4290
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 kernfs_iop_get_link fs/kernfs/symlink.c:135 [inline]
 kernfs_iop_get_link+0x65/0x860 fs/kernfs/symlink.c:126
 vfs_readlink+0x1e5/0x380 fs/namei.c:5267
 do_readlinkat+0x24c/0x390 fs/stat.c:551
 __do_sys_readlink fs/stat.c:574 [inline]
 __se_sys_readlink fs/stat.c:571 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:571
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efee0d17d47
RSP: 002b:00007ffd313bff28 EFLAGS: 00000246 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007ffd313bff38 RCX: 00007efee0d17d47
RDX: 0000000000000400 RSI: 00007ffd313bff38 RDI: 00007ffd313c0418
RBP: 0000000000000400 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd313c0418
R13: 00007ffd313c0388 R14: 00005593b70d82c0 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10562 jiffies! g16585 f0x2 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:27408 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5322 [inline]
 __schedule+0xef5/0x5750 kernel/sched/core.c:6682
 __schedule_loop kernel/sched/core.c:6759 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6774
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2615
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
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: 5305 Comm: kworker/1:5 Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:stack_trace_consume_entry+0x4e/0x170 kernel/stacktrace.c:86
Code: 04 02 84 c0 74 08 3c 03 0f 8e e7 00 00 00 48 8d 7b 08 8b 6b 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e ad 00 00 00 31 c0 3b 6b 08 0f 83 81 00 00
RSP: 0018:ffffc90000a18398 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffffc90000a18478 RCX: 0000000000000000
RDX: 1ffff92000143090 RSI: ffffffff8942afeb RDI: ffffc90000a18480
RBP: 0000000000000006 R08: ffffc90000a183ec R09: ffffffff9184d860
R10: ffffc90000a183b8 R11: 0000000000084242 R12: ffffffff81794f30
R13: ffffc90000a18478 R14: 0000000000000000 R15: ffff88807b5cbc00
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020025000 CR3: 000000005dee4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 arch_stack_walk+0x86/0x100 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4141
 __nf_conntrack_alloc+0xd1/0x5e0 net/netfilter/nf_conntrack_core.c:1677
 init_conntrack.constprop.0+0xd3e/0x1080 net/netfilter/nf_conntrack_core.c:1768
 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1888 [inline]
 nf_conntrack_in+0xafb/0x1850 net/netfilter/nf_conntrack_core.c:2040
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626
 nf_hook.constprop.0+0x42e/0x750 include/linux/netfilter.h:269
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_rcv+0x7d/0x5d0 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core+0x199/0x1e0 net/core/dev.c:5666
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5779
 process_backlog+0x443/0x15f0 net/core/dev.c:6111
 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6775
 napi_poll net/core/dev.c:6844 [inline]
 net_rx_action+0xa92/0x1010 net/core/dev.c:6966
 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554
 do_softirq kernel/softirq.c:455 [inline]
 do_softirq+0xb2/0xf0 kernel/softirq.c:442
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:382
 neigh_periodic_work+0x739/0xcf0 net/core/neighbour.c:1019
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>