rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2967/1:b..l (detected by 1, t=10503 jiffies, g=511749, q=75) task:systemd-udevd state:R running task stack:22672 pid: 2967 ppid: 1 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6687 irqentry_exit+0x31/0x80 kernel/entry/common.c:425 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:197 Code: 01 f0 4d 89 03 e9 63 fd ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 00 <65> 8b 05 89 e4 8b 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc900014df888 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000000 RDX: ffff88807b733900 RSI: ffffffff81d75ce1 RDI: 0000000000000003 RBP: ffffc900014df998 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff81d75cd7 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc900014dfd80 R14: dffffc0000000000 R15: dffffc0000000000 __seqprop_spinlock_sequence include/linux/seqlock.h:277 [inline] read_seqbegin include/linux/seqlock.h:840 [inline] read_seqbegin_or_lock include/linux/seqlock.h:1144 [inline] prepend_path+0x1d7/0xea0 fs/d_path.c:167 d_absolute_path+0xef/0x1a0 fs/d_path.c:235 tomoyo_get_absolute_path security/tomoyo/realpath.c:101 [inline] tomoyo_realpath_from_path+0x288/0x620 security/tomoyo/realpath.c:276 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x140 security/security.c:1333 vfs_getattr fs/stat.c:157 [inline] vfs_statx+0x164/0x390 fs/stat.c:225 vfs_fstatat fs/stat.c:243 [inline] vfs_lstat include/linux/fs.h:3356 [inline] __do_sys_newlstat+0x91/0x110 fs/stat.c:398 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f4fd6774335 RSP: 002b:00007ffdec4ecc28 EFLAGS: 00000246 ORIG_RAX: 0000000000000006 RAX: ffffffffffffffda RBX: 000055a5f4349b40 RCX: 00007f4fd6774335 RDX: 00007ffdec4ecc60 RSI: 00007ffdec4ecc60 RDI: 000055a5f4348b40 RBP: 00007ffdec4ecd20 R08: 00007f4fd6a33178 R09: 0000000000001010 R10: 00007f4fd6a32b58 R11: 0000000000000246 R12: 000055a5f4348b40 R13: 000055a5f4348b54 R14: 000055a5f4349b8d R15: 000055a5f4349b94 rcu: rcu_preempt kthread starved for 10530 jiffies! g511749 f0x0 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:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1957 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2130 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 23214 Comm: syz-executor.3 Not tainted 5.15.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:481 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline] check_cpu_stall kernel/rcu/tree_stall.h:729 [inline] rcu_pending kernel/rcu/tree.c:3880 [inline] rcu_sched_clock_irq+0x2125/0x2200 kernel/rcu/tree.c:2599 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 8a 89 23 f8 48 89 ef e8 d2 ff 23 f8 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 83 c0 17 f8 65 8b 05 5c 1a ca 76 85 c0 74 0a 5b 5d c3 e8 50 5f RSP: 0018:ffffc90000dc0b10 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff1fa108a RDX: 0000000000000000 RSI: 0000000000000102 RDI: 0000000000000001 RBP: ffffffff90469c28 R08: 0000000000000001 R09: ffffffff8fcfb947 R10: 0000000000000001 R11: 000000000000003f R12: 000000000000001f R13: 000000000000001f R14: dead000000000100 R15: dffffc0000000000 __debug_check_no_obj_freed lib/debugobjects.c:1002 [inline] debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1023 slab_free_hook mm/slub.c:1675 [inline] slab_free_freelist_hook+0xde/0x190 mm/slub.c:1725 slab_free mm/slub.c:3483 [inline] kfree+0xe4/0x530 mm/slub.c:4543 skb_free_head net/core/skbuff.c:654 [inline] skb_release_data+0x65a/0x790 net/core/skbuff.c:676 skb_release_all net/core/skbuff.c:741 [inline] __kfree_skb net/core/skbuff.c:755 [inline] consume_skb net/core/skbuff.c:911 [inline] consume_skb+0xc2/0x160 net/core/skbuff.c:905 mac80211_hwsim_tx_frame+0x1f6/0x2a0 drivers/net/wireless/mac80211_hwsim.c:1785 mac80211_hwsim_beacon_tx+0x49b/0x930 drivers/net/wireless/mac80211_hwsim.c:1838 __iterate_interfaces+0x1e5/0x520 net/mac80211/util.c:793 ieee80211_iterate_active_interfaces_atomic+0x70/0x180 net/mac80211/util.c:829 mac80211_hwsim_beacon+0xd5/0x1a0 drivers/net/wireless/mac80211_hwsim.c:1861 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:ct_state include/linux/context_tracking.h:98 [inline] RIP: 0010:schedule_debug kernel/sched/core.c:5514 [inline] RIP: 0010:__schedule+0xa06/0x26f0 kernel/sched/core.c:6178 Code: 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 bc 13 00 00 83 83 f4 0c 00 00 01 e9 0c f8 ff ff 65 8b 05 5a 49 cc 76 bc f7 ff ff 49 8d 7d 68 48 b8 00 00 00 00 00 fc ff df 48 89 fa RSP: 0018:ffffc900041d6b50 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000031a40 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900041d6c18 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000001 R12: ffff8880b9d31a40 R13: ffff888096cf0000 R14: ffffc900041d0000 R15: 0000000000000000 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6687 irqentry_exit+0x31/0x80 kernel/entry/common.c:425 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:batadv_hardif_get_by_netdev+0x137/0x400 net/batman-adv/hard-interface.c:70 Code: b3 02 00 00 4d 8b 24 24 49 81 fc 60 7f 60 90 0f 84 9b 01 00 00 e8 79 21 a5 f8 49 8d 7c 24 18 48 89 f8 48 c1 e8 03 80 3c 18 00 <0f> 85 94 02 00 00 4d 39 6c 24 18 75 b7 e8 57 21 a5 f8 49 8d 6c 24 RSP: 0018:ffffc900041d6cf8 EFLAGS: 00000246 RAX: 1ffff110039c3003 RBX: dffffc0000000000 RCX: ffffc90010028000 RDX: 0000000000040000 RSI: ffffffff88d0e9f7 RDI: ffff88801ce18018 RBP: ffff88814e540000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff88d0e976 R11: 0000000000000000 R12: ffff88801ce18000 R13: ffff88814e540000 R14: 0000000000000000 R15: ffffffff8d520ae0 batadv_hard_if_event+0x90/0x1640 net/batman-adv/hard-interface.c:932 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1996 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] register_netdevice+0xa5a/0x1500 net/core/dev.c:10294 macsec_newlink+0x424/0x17c0 drivers/net/macsec.c:4033 __rtnl_newlink+0x106d/0x1750 net/core/rtnetlink.c:3458 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3506 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf6efe549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f44f85fc EFLAGS: 00000296 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 0000000020000280 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 01 f0 add %esi,%eax 2: 4d 89 03 mov %r8,(%r11) 5: e9 63 fd ff ff jmpq 0xfffffd6d a: b9 ff ff ff ff mov $0xffffffff,%ecx f: ba 08 00 00 00 mov $0x8,%edx 14: 4d 8b 03 mov (%r11),%r8 17: 48 0f bd ca bsr %rdx,%rcx 1b: 49 8b 45 00 mov 0x0(%r13),%rax 1f: 48 63 c9 movslq %ecx,%rcx 22: e9 64 ff ff ff jmpq 0xffffff8b 27: 0f 1f 00 nopl (%rax) * 2a: 65 8b 05 89 e4 8b 7e mov %gs:0x7e8be489(%rip),%eax # 0x7e8be4ba <-- trapping instruction 31: 89 c1 mov %eax,%ecx 33: 48 8b 34 24 mov (%rsp),%rsi 37: 81 e1 00 01 00 00 and $0x100,%ecx 3d: 65 gs 3e: 48 rex.W 3f: 8b .byte 0x8b