rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5198/1:b..l rcu: (detected by 0, t=10503 jiffies, g=323121, q=456 ncpus=2) task:syslogd state:R running task stack:21632 pid:5198 tgid:5198 ppid:1 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7015 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:__sanitizer_cov_trace_const_cmp4+0x81/0x90 kernel/kcov.c:316 Code: 8d 42 28 4c 39 c8 77 22 89 f8 89 f6 49 ff c2 4c 89 11 48 c7 44 0a 08 05 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 RSP: 0018:ffffc900032a7648 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000080000000 RDX: ffff888046ca0000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 00000000000001a0 R08: ffffffff820ba0fd R09: 1ffffffff285a100 R10: dffffc0000000000 R11: fffffbfff285a101 R12: 000000000006870b R13: 0000000000000000 R14: ffffffff820b9f80 R15: ffff88801c380000 lookup_page_ext mm/page_ext.c:254 [inline] page_ext_get+0x19d/0x2a0 mm/page_ext.c:526 __page_table_check_zero+0xb1/0x350 mm/page_table_check.c:148 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1128 [inline] free_unref_page+0xe0e/0x1140 mm/page_alloc.c:2657 discard_slab mm/slub.c:2677 [inline] __put_partials+0xeb/0x130 mm/slub.c:3145 put_cpu_partial+0x17c/0x250 mm/slub.c:3220 __slab_free+0x2ea/0x3d0 mm/slub.c:4449 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:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283 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:2373 vfs_getattr+0x45/0x430 fs/stat.c:204 vfs_fstat fs/stat.c:229 [inline] vfs_fstatat+0xe4/0x190 fs/stat.c:338 __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: 0033:0x7f138f4c35f4 RSP: 002b:00007ffc93a7f3e8 EFLAGS: 00000206 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 000055a6a591f910 RCX: 00007f138f4c35f4 RDX: 00007ffc93a7f410 RSI: 00007f138f560130 RDI: 0000000000000003 RBP: 00007ffc93a7f4f0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000001000 R11: 0000000000000206 R12: 000055a6a591fc50 R13: 0000000067363569 R14: 0000000000000005 R15: 000055a6a591fa60 rcu: rcu_preempt kthread starved for 244 jiffies! g323121 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:25488 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6785 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: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc7-syzkaller-00070-g0a9b9d17f3a7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:check_preemption_disabled+0x6/0x120 lib/smp_processor_id.c:13 Code: c7 c6 00 0b 61 8c eb 1c 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 41 54 <53> 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 1d RSP: 0018:ffffc90000007390 EFLAGS: 00000282 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000080000101 RDX: ffffffff8e694640 RSI: ffffffff8c610b00 RDI: ffffffff8c610ac0 RBP: ffffc900000074d0 R08: ffffffff8a9b50e1 R09: 1ffffffff285a100 R10: dffffc0000000000 R11: fffffbfff285a101 R12: ffffc90000007420 R13: 0000000000000001 R14: ffff88802273d880 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fed76e00210 CR3: 0000000069304000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lockdep_current_cpu_online+0x37/0x120 kernel/rcu/tree.c:4774 rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 nf_hook include/linux/netfilter.h:244 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] br_nf_pre_routing_ipv6+0x50b/0x770 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424 __netif_receive_skb_core+0x13e8/0x4570 net/core/dev.c:5564 __netif_receive_skb_one_core net/core/dev.c:5668 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5783 process_backlog+0x662/0x15b0 net/core/dev.c:6115 __napi_poll+0xcb/0x490 net/core/dev.c:6779 napi_poll net/core/dev.c:6848 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6970 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 c0 d7 03 00 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d 05 ee a2 00 f3 0f 1e fa fb f4 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 RSP: 0018:ffffffff8e607ca8 EFLAGS: 00000246 RAX: ffffffff8e694640 RBX: ffff888020ad2864 RCX: 0000000000e69f89 RDX: 0000000000000001 RSI: ffff888020ad2800 RDI: ffff888020ad2864 RBP: 000000000003a9b8 R08: ffff8880b8637e9b R09: 1ffff110170c6fd3 R10: dffffc0000000000 R11: ffffffff8bc7ea50 R12: ffff88801e33e000 R13: 0000000000000001 R14: 0000000000000001 R15: ffffffff8f12ea20 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:702 cpuidle_enter_state+0x109/0x470 drivers/cpuidle/cpuidle.c:264 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:385 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x375/0x5d0 kernel/sched/idle.c:326 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424 rest_init+0x2dc/0x300 init/main.c:747 start_kernel+0x47f/0x500 init/main.c:1105 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147