rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5832/1:b..l P5504/1:b..l P4167/1:b..l rcu: (detected by 0, t=10502 jiffies, g=137445, q=80 ncpus=1) task:dhcpcd state:R running task stack:28480 pid:4167 tgid:4167 ppid:5505 task_flags:0x400140 flags:0x00000002 Call Trace: <TASK> context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087 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:write_comp_data+0x3/0x90 kernel/kcov.c:240 Code: 13 02 4a 7e 48 8b 80 20 16 00 00 c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 <49> 89 f8 49 89 f1 65 48 8b 15 df 01 4a 7e 65 8b 05 e0 01 4a 7e a9 RSP: 0018:ffffc9000435f6f8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8225a235 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000004 RBP: ffff88801e43bf10 R08: 0000000000000003 R09: 000000000000001f R10: 0000000000000001 R11: 0000000000000002 R12: 0000000002960487 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000004 __update_page_owner_free_handle mm/page_owner.c:268 [inline] __reset_page_owner+0x275/0x400 mm/page_owner.c:298 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 __put_partials+0x14c/0x170 mm/slub.c:3153 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/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:4294 [inline] __kmalloc_node_track_caller_noprof+0x222/0x510 mm/slub.c:4313 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:537 __alloc_skb+0x164/0x380 net/core/skbuff.c:606 alloc_skb include/linux/skbuff.h:1331 [inline] alloc_skb_with_frags+0xe4/0x850 net/core/skbuff.c:6522 sock_alloc_send_pskb+0x7f1/0x980 net/core/sock.c:2897 unix_dgram_sendmsg+0x45e/0x18c0 net/unix/af_unix.c:2017 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] __sys_sendto+0x488/0x4f0 net/socket.c:2187 __do_sys_sendto net/socket.c:2194 [inline] __se_sys_sendto net/socket.c:2190 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2190 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: 0033:0x7fdc3b1289b5 RSP: 002b:00007ffed294dbb8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000000006b RCX: 00007fdc3b1289b5 RDX: 000000000000004e RSI: 00005617ee45f2b0 RDI: 0000000000000004 RBP: 00005617ee454cb0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000014 R13: 00005617cce9a6ea R14: 00007ffed294e0f0 R15: 0000000000000000 </TASK> task:dhcpcd state:R running task stack:24240 pid:5504 tgid:5504 ppid:1 task_flags:0x400140 flags:0x00004002 Call Trace: <TASK> context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6944 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194 sock_def_readable+0x15f/0x610 net/core/sock.c:3476 unix_dgram_sendmsg+0xd79/0x18c0 net/unix/af_unix.c:2163 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] sock_write_iter+0x4fe/0x5b0 net/socket.c:1137 do_iter_readv_writev+0x655/0x950 fs/read_write.c:820 vfs_writev+0x363/0xdd0 fs/read_write.c:1050 do_writev+0x297/0x340 fs/read_write.c:1096 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: 0033:0x7fdc3b11ee03 RSP: 002b:00007ffed296e828 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007ffed296eb88 RCX: 00007fdc3b11ee03 RDX: 0000000000000005 RSI: 00007ffed296e840 RDI: 000000000000000a RBP: 000000000000012c R08: 000000000000000a R09: 00007ffed296e880 R10: 00007ffed296e888 R11: 0000000000000246 R12: 00005617ee44d240 R13: 00005617cce7ff88 R14: 00000000ffffffff R15: 0000000000000001 </TASK> task:syz-executor state:R running task stack:23360 pid:5832 tgid:5832 ppid:5829 task_flags:0x400140 flags:0x00004002 Call Trace: <TASK> context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7087 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:lock_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5816 Code: b8 ff ff ff ff 65 0f c1 05 e0 da 6b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc90003cf77c0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff9200079eef9 RCX: 00000000d9425282 RDX: 0000000000000001 RSI: ffffffff8b6cf020 RDI: ffffffff8bd34640 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dd7d98 R10: ffffffff96ebecc7 R11: 0000000000000004 R12: 0000000000000000 R13: ffffffff8e1bcc80 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3a/0x310 mm/page_ext.c:525 __reset_page_owner+0x32/0x400 mm/page_owner.c:290 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/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:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_noprof+0x1cd/0x510 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] tomoyo_realpath_from_path+0xb9/0x720 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x276/0x460 security/tomoyo/file.c:822 tomoyo_path_unlink+0x92/0xe0 security/tomoyo/tomoyo.c:162 security_path_unlink+0x145/0x2b0 security/security.c:1965 do_unlinkat+0x50b/0x760 fs/namei.c:4586 __do_sys_unlink fs/namei.c:4637 [inline] __se_sys_unlink fs/namei.c:4635 [inline] __x64_sys_unlink+0xc5/0x110 fs/namei.c:4635 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: 0033:0x7f7a4138c717 RSP: 002b:00007ffea27367c8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7a4138c717 RDX: 00007ffea27367f0 RSI: 00007ffea2736880 RDI: 00007ffea2736880 RBP: 00007ffea2736880 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffea2737910 R13: 00007f7a4140e08c R14: 00000000000dd76f R15: 00007ffea2737950 </TASK> rcu: rcu_preempt kthread starved for 9094 jiffies! g137445 f0x0 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:27552 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 3401 Comm: kworker/R-bat_e Tainted: G U 6.14.0-rc3-syzkaller-00293-g5cf80612d3f7 #0 Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_dat_purge RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 7e 60 e8 a3 ff ff ff 31 c0 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 65 48 8b 15 24 fb 49 7e 65 8b 05 25 fb 49 7e a9 00 01 RSP: 0018:ffffc900000069e8 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff8881a7879c80 RCX: ffffffff893233df RDX: ffff888031cf1e00 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff88807e105000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000005 R12: ffff888027d00000 R13: 0000000000000001 R14: ffff8881a7879d01 R15: ffff88807ea72000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdc3b101580 CR3: 000000007d418000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> __dev_queue_xmit+0x60c/0x43e0 net/core/dev.c:4620 dev_queue_xmit include/linux/netdevice.h:3313 [inline] br_dev_queue_push_xmit+0x274/0x8a0 net/bridge/br_forward.c:53 br_nf_dev_queue_xmit+0x6db/0x2c50 net/bridge/br_netfilter_hooks.c:923 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] br_nf_post_routing+0x8ee/0x11b0 net/bridge/br_netfilter_hooks.c:969 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626 nf_hook+0x474/0x7d0 include/linux/netfilter.h:269 NF_HOOK include/linux/netfilter.h:312 [inline] br_forward_finish+0xcd/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh+0x303/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_forward_finish+0x66a/0xba0 net/bridge/br_netfilter_hooks.c:665 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] br_nf_forward_ip.part.0+0x610/0x820 net/bridge/br_netfilter_hooks.c:719 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:679 [inline] br_nf_forward+0xf11/0x1bd0 net/bridge/br_netfilter_hooks.c:776 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626 nf_hook+0x474/0x7d0 include/linux/netfilter.h:269 NF_HOOK include/linux/netfilter.h:312 [inline] __br_forward+0x1be/0x5b0 net/bridge/br_forward.c:115 deliver_clone+0x5b/0xa0 net/bridge/br_forward.c:131 br_flood+0x491/0x5e0 net/bridge/br_forward.c:249 br_handle_frame_finish+0xea2/0x1c90 net/bridge/br_input.c:220 br_nf_hook_thresh+0x303/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_pre_routing_finish_ipv6+0x76a/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x3ce/0x8c0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:282 [inline] br_handle_frame+0xad7/0x14a0 net/bridge/br_input.c:433 __netif_receive_skb_core.constprop.0+0xa20/0x4330 net/core/dev.c:5793 __netif_receive_skb_one_core+0xb1/0x1e0 net/core/dev.c:5897 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6012 process_backlog+0x443/0x15f0 net/core/dev.c:6360 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7194 napi_poll net/core/dev.c:7263 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7385 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 do_softirq kernel/softirq.c:462 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:449 </IRQ> <TASK> __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:389 spin_unlock_bh include/linux/spinlock.h:396 [inline] __batadv_dat_purge.part.0+0x279/0x3a0 net/batman-adv/distributed-arp-table.c:185 __batadv_dat_purge net/batman-adv/distributed-arp-table.c:166 [inline] batadv_dat_purge+0x4b/0xa0 net/batman-adv/distributed-arp-table.c:204 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] rescuer_thread+0x616/0xe80 kernel/workqueue.c:3494 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK>