rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4687/1:b..l P81/2:b..l rcu: (detected by 1, t=10503 jiffies, g=5249, q=1863769 ncpus=2) task:kworker/u8:4 state:R running task stack:21488 pid:81 tgid:81 ppid:2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6854 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6878 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x179/0x200 kernel/softirq.c:389 local_bh_enable include/linux/bottom_half.h:33 [inline] ip6t_do_table+0x1687/0x18a0 net/ipv6/netfilter/ip6_tables.c:375 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ndisc_send_skb+0x122f/0x1380 net/ipv6/ndisc.c:511 ndisc_send_ns+0xcc/0x160 net/ipv6/ndisc.c:669 addrconf_dad_work+0xb45/0x16f0 net/ipv6/addrconf.c:4284 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:udevd state:R running task stack:24960 pid:4687 tgid:4687 ppid:1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6997 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5829 Code: 2b 00 74 08 4c 89 f7 e8 aa 46 8e 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900034af4a0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000695ea0 RCX: 5983e4fefdb4e900 RDX: dffffc0000000000 RSI: ffffffff8c0adc40 RDI: ffffffff8c60f860 RBP: ffffc900034af5f0 R08: ffffffff942c5807 R09: 1ffffffff2858b00 R10: dffffc0000000000 R11: fffffbfff2858b01 R12: 1ffff92000695e9c R13: dffffc0000000000 R14: ffffc900034af500 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 __reset_page_owner+0x30/0x430 mm/page_owner.c:290 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 __slab_free+0x31b/0x3d0 mm/slub.c:4491 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4277 kmalloc_noprof include/linux/slab.h:882 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822 security_inode_getattr+0x130/0x330 security/security.c:2371 vfs_getattr+0x45/0x430 fs/stat.c:204 vfs_statx_path fs/stat.c:251 [inline] vfs_statx+0x199/0x490 fs/stat.c:315 vfs_fstatat+0x145/0x190 fs/stat.c:341 __do_sys_newfstatat fs/stat.c:505 [inline] __se_sys_newfstatat fs/stat.c:499 [inline] __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:499 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f78d97165f4 RSP: 002b:00007ffe1615eec8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 000055a713b806d0 RCX: 00007f78d97165f4 RDX: 00007ffe1615eed8 RSI: 000055a713b6e7ff RDI: 00000000ffffff9c RBP: 000055a740deefb8 R08: 00062305ed946d00 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00062305ed946d00 R15: 000055a713b74dca rcu: rcu_preempt kthread starved for 10544 jiffies! g5249 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:24024 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 2542 Comm: kworker/u8:7 Not tainted 6.12.0-rc1-syzkaller-00242-g1405981bbba0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x84/0x2050 kernel/locking/lockdep.c:5065 Code: 89 54 24 54 89 5c 24 68 4c 89 f8 48 c1 e8 03 80 3c 30 00 74 12 4c 89 ff e8 c9 41 8e 00 48 be 00 00 00 00 00 fc ff df 49 8b 07 <48> c7 c1 d0 56 e3 93 48 39 c8 0f 84 7c 13 00 00 8b 0d 96 f6 0f 0d RSP: 0018:ffffc90000006690 EFLAGS: 00000046 RAX: ffffffff8e958608 RBX: 0000000000000002 RCX: 0000000000000002 RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffffffff8e958608 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: dffffc0000000000 R11: fffffbfff2039cee R12: ffff88802db39e00 R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff8e958608 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff832fdd4c CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 seqcount_lockdep_reader_access+0x13f/0x220 include/linux/seqlock.h:73 ktime_get_with_offset+0x83/0x150 kernel/time/timekeeping.c:891 ktime_get_real include/linux/timekeeping.h:82 [inline] netif_rx_internal+0x459/0x630 net/core/dev.c:5172 __netif_rx+0x78/0xc0 net/core/dev.c:5215 loopback_xmit+0x454/0x6b0 drivers/net/loopback.c:89 __netdev_start_xmit include/linux/netdevice.h:4920 [inline] netdev_start_xmit include/linux/netdevice.h:4929 [inline] xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3604 __dev_queue_xmit+0x1b11/0x3ed0 net/core/dev.c:4428 dev_queue_xmit include/linux/netdevice.h:3098 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:236 synproxy_send_client_synack+0x8b8/0xf30 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcb/0x490 net/core/dev.c:6775 napi_poll net/core/dev.c:6844 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6966 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x312/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x365/0x610 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.710 msecs