rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5232/1:b..l P26/1:b..l P17102/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=84721, q=1183136 ncpus=2)
task:syz-executor    state:R  running task     stack:21248 pid:17102 tgid:17102 ppid:1      task_flags:0x40054c flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 zap_pte_range mm/memory.c:1884 [inline]
 zap_pmd_range mm/memory.c:1946 [inline]
 zap_pud_range mm/memory.c:1975 [inline]
 zap_p4d_range mm/memory.c:1996 [inline]
 unmap_page_range+0x3a7f/0x4370 mm/memory.c:2017
 unmap_single_vma mm/memory.c:2060 [inline]
 unmap_vmas+0x399/0x580 mm/memory.c:2104
 exit_mmap+0x248/0xb50 mm/mmap.c:1280
 __mmput+0x118/0x420 kernel/fork.c:1133
 exit_mm+0x1da/0x2c0 kernel/exit.c:582
 do_exit+0x648/0x2300 kernel/exit.c:949
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x130 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a4ed84e57
RSP: 002b:00007ffdab752bb0 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: 0000000000000219 RBX: 0000000000000219 RCX: 00007f1a4ed84e57
RDX: 0000000040000000 RSI: 00007ffdab752c1c RDI: 00000000ffffffff
RBP: 00007ffdab752c1c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000096
R13: 00005555892d2590 R14: 000000000014e85d R15: 00007ffdab752c70
 </TASK>
task:kdevtmpfs       state:R  running task     stack:24904 pid:26    tgid:26    ppid:2      task_flags:0x208140 flags:0x00004000
Call Trace:
 <TASK>
 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:697
RIP: 0010:page_ext_lookup+0x5/0x180 mm/page_ext.c:508
Code: 90 90 90 90 90 66 0f 1f 00 e8 f7 4a 91 ff e9 c2 41 52 09 cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 <41> 57 41 56 41 55 41 54 53 48 89 fb e8 ca 4a 91 ff 49 89 dc 49 c1
RSP: 0018:ffffc90000a176d8 EFLAGS: 00000206
RAX: 1ffffffff1bbb8a3 RBX: dffffc0000000000 RCX: ffff88801daf0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000041cbe
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000010 R11: ffffffff81ad2180 R12: 0000000000041cbe
R13: 0000000000000000 R14: ffffffff822d88ae R15: 00000149cda0d06a
 page_ext_iter_begin include/linux/page_ext.h:132 [inline]
 __update_page_owner_free_handle+0x103/0x470 mm/page_owner.c:272
 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:309
 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
 __slab_free+0x2e7/0x390 mm/slub.c:4591
 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:349
 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_lru_noprof+0x1b2/0x390 mm/slub.c:4248
 shmem_alloc_inode+0x28/0x40 mm/shmem.c:5211
 alloc_inode+0x67/0x1b0 fs/inode.c:346
 new_inode+0x22/0x170 fs/inode.c:1145
 __shmem_get_inode mm/shmem.c:3110 [inline]
 shmem_get_inode+0x346/0xe90 mm/shmem.c:3184
 shmem_mknod+0x18c/0x3e0 mm/shmem.c:3905
 vfs_mknod+0x37c/0x3c0 fs/namei.c:4235
 handle_create drivers/base/devtmpfs.c:233 [inline]
 handle drivers/base/devtmpfs.c:389 [inline]
 devtmpfs_work_loop+0x98b/0xd20 drivers/base/devtmpfs.c:404
 devtmpfsd+0x4d/0x50 drivers/base/devtmpfs.c:446
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
task:udevd           state:R  running task     stack:22920 pid:5232  tgid:5232  ppid:1      task_flags:0x400140 flags:0x00004002
Call Trace:
 <TASK>
 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:697
RIP: 0010:__reset_page_owner+0x55/0x1f0 mm/page_owner.c:299
Code: 0f 84 52 01 00 00 48 8b 0d 28 df 19 0c 48 8d 1c 08 48 83 c3 08 48 89 d9 48 c1 e9 03 48 ba 00 00 00 00 00 fc ff df 0f b6 0c 11 <84> c9 0f 85 49 01 00 00 8b 1b 48 89 c7 e8 99 c3 01 00 bf 00 20 00
RSP: 0018:ffffc90003367608 EFLAGS: 00000a02
RAX: ffff88801cd5d600 RBX: ffff88801cd5d610 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff94000222f07 R12: 0000000000000000
R13: 0000000000000000 R14: ffffea0001117800 R15: 0000014860d930bb
 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+0x146/0x170 mm/slub.c:3218
 put_cpu_partial+0x17c/0x250 mm/slub.c:3293
 __slab_free+0x2b9/0x390 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:349
 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+0x210/0x4b0 mm/slub.c:4377
 kmalloc_noprof include/linux/slab.h:913 [inline]
 kzalloc_noprof include/linux/slab.h:1043 [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:2416
 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/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa1f4911b0a
RSP: 002b:00007ffd31d10568 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 000055b0ef176420 RCX: 00007fa1f4911b0a
RDX: 00007ffd31d10570 RSI: 000055b0ef164ef3 RDI: 00000000ffffff9c
RBP: 000055b113889148 R08: 00063478c1c69200 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffd31d10570 R14: 0000000000000000 R15: 00063478c1c69200
 </TASK>
rcu: rcu_preempt kthread starved for 6337 jiffies! g84721 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:I stack:26464 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 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+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 1299 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:timerqueue_getnext include/linux/timerqueue.h:25 [inline]
RIP: 0010:__hrtimer_next_event_base+0xa0/0x2d0 kernel/time/hrtimer.c:523
Code: 09 00 00 00 44 89 fe e8 5e 0c 12 00 41 83 ff 09 0f 83 00 02 00 00 e8 0f 08 12 00 48 c1 e5 07 48 03 6c 24 18 0f 84 fa 01 00 00 <4c> 8d 7d 58 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80
RSP: 0018:ffffc90000a079c0 EFLAGS: 00000086
RAX: ffffffff81ae86c1 RBX: 0000000000000000 RCX: ffff888027738000
RDX: 0000000000010100 RSI: 0000000000000000 RDI: 0000000000000009
RBP: ffff8880b8727b00 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000140ef4 R12: 7fffffffffffffff
R13: 00000162e86d6e76 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125aff000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4a6e3f02ec CR3: 000000007b332000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __hrtimer_get_next_event kernel/time/hrtimer.c:596 [inline]
 hrtimer_update_next_event kernel/time/hrtimer.c:621 [inline]
 hrtimer_interrupt+0x568/0xaa0 kernel/time/hrtimer.c:1890
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2ad/0x3e0 kernel/locking/lockdep.c:5893
Code: 59 f9 23 11 83 f8 01 75 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb <65> 48 8b 05 1b b9 23 11 48 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4
RSP: 0018:ffffc90000a07c30 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff90e07c01 RCX: adb7227343033600
RDX: ffffc90000a07d01 RSI: ffffffff8c035860 RDI: ffffffff8c035820
RBP: dffffc0000000000 R08: ffffc90000a086f0 R09: 0000000000000000
R10: ffffc90000a07db8 R11: fffff52000140fb9 R12: ffffc90000a08700
R13: ffffffff8173a1d5 R14: ffffffff8e33bfe0 R15: ffffffff8173a1d5
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559
 __call_rcu_common kernel/rcu/tree.c:3123 [inline]
 call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243
 refdst_drop include/net/dst.h:263 [inline]
 skb_dst_drop include/net/dst.h:275 [inline]
 skb_release_head_state+0x71/0x250 net/core/skbuff.c:1135
 skb_release_all net/core/skbuff.c:1149 [inline]
 __kfree_skb net/core/skbuff.c:1165 [inline]
 consume_skb+0x60/0xf0 net/core/skbuff.c:1397
 nft_synproxy_eval_v4+0x376/0x560 net/netfilter/nft_synproxy.c:60
 nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
 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:5991 [inline]
 __netif_receive_skb+0x143/0x380 net/core/dev.c:6104
 process_backlog+0x60e/0x14f0 net/core/dev.c:6456
 __napi_poll+0xc4/0x360 net/core/dev.c:7506
 napi_poll net/core/dev.c:7569 [inline]
 net_rx_action+0x707/0xe30 net/core/dev.c:7696
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 do_softirq+0xec/0x180 kernel/softirq.c:480
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline]
 __dev_queue_xmit+0x1d79/0x3b50 net/core/dev.c:4752
 dev_queue_xmit include/linux/netdevice.h:3361 [inline]
 tx+0x6b/0x190 drivers/block/aoe/aoenet.c:62
 kthread+0x1cd/0x3e0 drivers/block/aoe/aoecmd.c:1241
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>