rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5866/1:b..l P5858/1:b..l P84/1:b..l P11403/1:b..l rcu: (detected by 1, t=10503 jiffies, g=28137, q=1499 ncpus=2) task:syz-executor state:R running task stack:25224 pid:11403 tgid:11403 ppid:5837 task_flags:0x400000 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_read_lock include/linux/rcupdate.h:842 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1155 [inline] RIP: 0010:unwind_next_frame+0xcd/0x2390 arch/x86/kernel/unwind_orc.c:479 Code: 00 00 48 c7 c7 a0 9e 13 8e 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 ae 98 2a 00 48 83 c4 08 e8 25 bd 06 0a 85 c0 <74> 3a e8 5c 9b 33 00 84 c0 75 31 e8 13 bd 06 0a 85 c0 74 28 80 3d RSP: 0018:ffffc9000c7f7878 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff822325c8 RCX: f337c1c7d6dc3d00 RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff8be33620 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff81ac3810 R12: 1ffff920018fef29 R13: ffffc9000c7f7980 R14: ffffc9000c7f7948 R15: ffffffff8172c195 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x156/0x1a0 mm/slub.c:3218 put_cpu_partial+0x17c/0x250 mm/slub.c:3293 __slab_free+0x2d5/0x3c0 mm/slub.c:4550 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 getname_flags+0xb8/0x540 fs/namei.c:146 getname include/linux/fs.h:2918 [inline] __do_sys_mkdir fs/namei.c:4421 [inline] __se_sys_mkdir fs/namei.c:4419 [inline] __x64_sys_mkdir+0x5d/0x80 fs/namei.c:4419 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3b3fdc2857 RSP: 002b:00007ffe953bd838 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffe953bd982 RCX: 00007f3b3fdc2857 RDX: 000000000e3c089d RSI: 00000000000001c0 RDI: 00007ffe953bd970 RBP: f49998db0aa753ff R08: 0000000000000004 R09: 0000000000000001 R10: 3fffffffffffffff R11: 0000000000000246 R12: 8421084210842109 R13: 00007ffe953bd982 R14: 00007f3b3fe4f6c0 R15: 000000000e3c089d task:kswapd0 state:R running task stack:25136 pid:84 tgid:84 ppid:2 task_flags:0x220840 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:86 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0xa8/0x2c0 mm/kasan/generic.c:189 Code: 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 41 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 0f 85 de 01 00 00 49 ff c3 <48> ff c3 75 ee e9 21 01 00 00 44 89 dd 83 e5 07 0f 84 b5 00 00 00 RSP: 0018:ffffc9000212ea80 EFLAGS: 00000282 RAX: 1ffff92000425d01 RBX: fffffffffffffffe RCX: ffffffff8172cd88 RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc9000212ec58 RBP: 0000000000000000 R08: ffffc9000212ec67 R09: 1ffff92000425d8c R10: dffffc0000000000 R11: fffff52000425d8c R12: 0000000000000002 R13: ffffc9000212ec58 R14: fffff52000425d8d R15: 1ffff92000425d8b __asan_memset+0x22/0x50 mm/kasan/shadow.c:84 unwind_next_frame+0xc98/0x2390 arch/x86/kernel/unwind_orc.c:592 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 __call_rcu_common kernel/rcu/tree.c:3123 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243 destroy_inode fs/inode.c:401 [inline] evict+0x847/0x9c0 fs/inode.c:834 __dentry_kill+0x209/0x660 fs/dcache.c:669 shrink_kill+0xa9/0x2c0 fs/dcache.c:1114 shrink_dentry_list+0x2e0/0x5e0 fs/dcache.c:1141 prune_dcache_sb+0x10e/0x180 fs/dcache.c:1222 super_cache_scan+0x369/0x4b0 fs/super.c:222 do_shrink_slab+0x6ef/0x1110 mm/shrinker.c:437 shrink_slab+0xd74/0x10d0 mm/shrinker.c:664 shrink_one+0x28a/0x7c0 mm/vmscan.c:4954 shrink_many mm/vmscan.c:5015 [inline] lru_gen_shrink_node mm/vmscan.c:5093 [inline] shrink_node+0x314e/0x3760 mm/vmscan.c:6078 kswapd_shrink_node mm/vmscan.c:6938 [inline] balance_pgdat mm/vmscan.c:7121 [inline] kswapd+0x147c/0x2830 mm/vmscan.c:7386 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 task:syz-executor state:R running task stack:21960 pid:5858 tgid:5858 ppid:5846 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:page_ext_get+0xbc/0x2f0 include/linux/rcupdate.h:-1 Code: 4a 7a 91 ff eb 24 e8 43 7a 91 ff c6 05 80 19 5f 0d 01 48 c7 c7 60 d6 98 8b be 4b 03 00 00 48 c7 c2 40 d8 98 8b e8 94 54 6f ff <49> bd 00 00 00 00 00 fc ff df 48 c7 c0 78 64 bd 8d 48 c1 e8 03 42 RSP: 0018:ffffc90002e679c8 EFLAGS: 00000293 RAX: ffffffff822e30bb RBX: ffffffff822e3072 RCX: ffff888079ccda00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff9400043ada7 R12: 0000000000000000 R13: 0000000000000000 R14: ffffea00021d6d00 R15: 0000004418253dd3 __reset_page_owner+0x28/0x1f0 mm/page_owner.c:294 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x156/0x1a0 mm/slub.c:3218 put_cpu_partial+0x17c/0x250 mm/slub.c:3293 __slab_free+0x2d5/0x3c0 mm/slub.c:4550 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:396 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4365 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] lsm_blob_alloc security/security.c:684 [inline] lsm_sock_alloc security/security.c:4869 [inline] security_sk_alloc+0x52/0x390 security/security.c:4885 sk_prot_alloc+0x101/0x220 net/core/sock.c:2242 sk_alloc+0x3a/0x370 net/core/sock.c:2295 inet6_create+0x7f0/0x1260 net/ipv6/af_inet6.c:193 __sock_create+0x4b3/0x9f0 net/socket.c:1589 sock_create net/socket.c:1647 [inline] __sys_socket_create net/socket.c:1684 [inline] __sys_socket+0xd7/0x1b0 net/socket.c:1731 __do_sys_socket net/socket.c:1745 [inline] __se_sys_socket net/socket.c:1743 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1743 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7b47f90b07 RSP: 002b:00007ffd3e4d5c88 EFLAGS: 00000206 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f7b47f90b07 RDX: 0000000000000006 RSI: 0000000000000001 RDI: 000000000000000a RBP: 00007ffd3e4d63bc R08: 0000000000000000 R09: 00007ffd3e4d60c7 R10: 0000000000000000 R11: 0000000000000206 R12: 00007f7b48182ca0 R13: 0000000000000063 R14: 000000000003097f R15: 00007f7b48184e60 task:syz-executor state:R running task stack:21960 pid:5866 tgid:5866 ppid:5845 task_flags:0x400140 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:srso_alias_safe_ret+0x5/0x7 arch/x86/lib/retpoline.S:175 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 48 8d 64 24 08 cc e8 f4 ff ff ff 0f 0b cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 0018:ffffc90003eaf2b0 EFLAGS: 00000202 RAX: ffffffff82355a0e RBX: ffffc90003eafc18 RCX: 1ffff920007d5e01 RDX: ffffffff9065a052 RSI: 0000000000000002 RDI: ffffc90003eafc18 RBP: 1ffff920007d5e72 R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff81ac3810 R12: ffffc90003eb0000 R13: 1ffff920007d5e73 R14: ffffc90003eaf388 R15: ffffc90003ea8000 deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline] unwind_next_frame+0xc3c/0x2390 arch/x86/kernel/unwind_orc.c:585 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x156/0x1a0 mm/slub.c:3218 put_cpu_partial+0x17c/0x250 mm/slub.c:3293 __slab_free+0x2d5/0x3c0 mm/slub.c:4550 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x224/0x4f0 mm/slub.c:4377 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x213/0x4b0 security/tomoyo/file.c:822 security_inode_getattr+0x12f/0x330 security/security.c:2377 vfs_getattr fs/stat.c:259 [inline] vfs_statx_path fs/stat.c:299 [inline] vfs_statx+0x18e/0x550 fs/stat.c:356 vfs_fstatat+0x118/0x170 fs/stat.c:375 __do_sys_newfstatat fs/stat.c:542 [inline] __se_sys_newfstatat fs/stat.c:536 [inline] __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2b7d58d3fa RSP: 002b:00007ffd54cad328 EFLAGS: 00000286 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2b7d58d3fa RDX: 00007ffd54cad350 RSI: 00007ffd54cad3e0 RDI: 00000000ffffff9c RBP: 00007ffd54cad3e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000286 R12: 00007ffd54cae470 R13: 00007f2b7d611c05 R14: 00000000000370b0 R15: 00007ffd54cae4b0 rcu: rcu_preempt kthread starved for 10449 jiffies! g28137 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:26920 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:ip_vs_in_hook+0x17c/0x1be0 net/netfilter/ipvs/ip_vs_core.c:1924 Code: 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 af 15 00 00 8b 1a 89 de 81 e6 00 00 08 00 31 ff e8 8a 58 dd f7 81 e3 00 00 08 00 <0f> 85 af 00 00 00 4c 89 7c 24 50 48 8d bc 24 f0 00 00 00 ba 34 00 RSP: 0018:ffffc90000a08580 EFLAGS: 00000246 RAX: ffffffff89e256e6 RBX: 0000000000000000 RCX: 0000000000000100 RDX: ffff88801ce95a00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a08760 R08: ffff88801ce95a00 R09: 0000000000000004 R10: 0000000000000003 R11: ffffffff89e25570 R12: ffff888067b8c000 R13: dffffc0000000000 R14: ffff8880309f6000 R15: 1ffff1100cf71810 FS: 0000000000000000(0000) GS:ffff888125d1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000022d030 CR3: 0000000025644000 CR4: 0000000000350ef0 Call Trace: nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:5979 [inline] __netif_receive_skb+0x143/0x380 net/core/dev.c:6092 process_backlog+0x60e/0x14f0 net/core/dev.c:6444 __napi_poll+0xc7/0x360 net/core/dev.c:7494 napi_poll net/core/dev.c:7557 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7684 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 3e cd 96 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 b6 0e 00 f3 0f 1e fa fb f4 13 cd 96 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2 RAX: 9dd9d7740035d400 RBX: ffffffff819683b8 RCX: 9dd9d7740035d400 RDX: 0000000000000001 RSI: ffffffff8be33660 RDI: ffffffff819683b8 RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3 R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fa38330 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d2b40 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147