rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6216/1:b..l rcu: (detected by 1, t=10502 jiffies, g=9425, q=1360134 ncpus=2) task:syz.2.231 state:R running task stack:26472 pid:6216 tgid:6214 ppid:5229 flags:0x00000000 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:__kernel_text_address+0x5/0x40 kernel/extable.c:78 Code: c3 48 c7 c7 c0 a6 1c 90 e8 88 c5 9e 00 eb b5 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 53 <48> 89 fb e8 43 00 00 00 85 c0 0f 95 c0 48 c7 c1 00 90 7b 91 48 39 RSP: 0018:ffffc90009e1f4f0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc90009e1f568 RCX: 0000000080000000 RDX: dffffc0000000000 RSI: ffffc90009e18000 RDI: ffffffff8bc4f3d3 RBP: ffffc90009e1f5b0 R08: ffffc90009e1ff00 R09: 0000000000000000 R10: ffffc90009e1f570 R11: fffff520013c3eb0 R12: ffff88802ad43c00 R13: ffffffff81808f50 R14: dffffc0000000000 R15: 1ffff920013c3ead unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 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+0xcfb/0xf20 mm/page_alloc.c:2638 discard_slab mm/slub.c:2678 [inline] __put_partials+0xeb/0x130 mm/slub.c:3146 put_cpu_partial+0x17c/0x250 mm/slub.c:3221 __slab_free+0x2ea/0x3d0 mm/slub.c:4450 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] 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_number_perm+0x23a/0x880 security/tomoyo/file.c:723 security_file_ioctl+0xc6/0x2a0 security/security.c:2908 __do_sys_ioctl fs/ioctl.c:901 [inline] __se_sys_ioctl+0x47/0x170 fs/ioctl.c:893 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: 0033:0x7f54bbd7dbfb RSP: 002b:00007f54bcad4060 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f54bbd7dbfb RDX: 0000000000000000 RSI: 0000000000006364 RDI: 00000000000000d9 RBP: 00007f54bbf36058 R08: 0000000000000000 R09: 00007fff135bccd7 R10: 0000000000000008 R11: 0000000000000246 R12: 00007f54bbf36064 R13: 0000000000000001 R14: 00007fff135bcbf0 R15: 00007fff135bccd8 rcu: rcu_preempt kthread starved for 10031 jiffies! g9425 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:25816 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: CPU: 1 UID: 0 PID: 5331 Comm: kworker/1:7 Not tainted 6.12.0-rc1-syzkaller-00229-gd521db38f339 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:unwind_next_frame+0x311/0x22d0 arch/x86/kernel/unwind_orc.c:505 Code: 02 4b 8d 14 64 48 01 d2 48 01 f2 0f 84 42 01 00 00 48 8d 5a 04 4c 8d 72 05 48 89 d8 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df <0f> b6 04 28 84 c0 0f 85 58 18 00 00 4c 89 f0 48 c1 e8 03 0f b6 04 RSP: 0018:ffffc90000a17f50 EFLAGS: 00000a02 RAX: 1ffffffff224fc16 RBX: ffffffff9127e0b2 RCX: ffffffff908626dc RDX: ffffffff9127e0ae RSI: ffffffff9127e0a8 RDI: 0000000000000001 RBP: dffffc0000000000 R08: 0000000000000002 R09: ffffc90000a18110 R10: ffffc90000a18070 R11: ffffffff81808f50 R12: 0000000000000001 R13: ffffc90000a18020 R14: ffffffff9127e0b3 R15: ffffffff89d9feb2 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f54bcad3f98 CR3: 000000006e020000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:3086 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3190 slab_free_hook mm/slub.c:2307 [inline] slab_free mm/slub.c:4580 [inline] kmem_cache_free+0x2fc/0x420 mm/slub.c:4682 nf_conntrack_free+0x2fd/0x390 net/netfilter/nf_conntrack_core.c:1735 nf_ct_put include/net/netfilter/nf_conntrack.h:186 [inline] nf_conntrack_in+0xb51/0x1890 net/netfilter/nf_conntrack_core.c:2061 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 __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] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x75d/0xaa0 drivers/net/netdevsim/dev.c:850 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