rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16877/1:b..l rcu: (detected by 1, t=10503 jiffies, g=129793, q=1298675 ncpus=2) task:syz.3.2643 state:R running task stack:24896 pid:16877 tgid:16876 ppid:16472 flags:0x20004006 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6708 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6732 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1688 [inline] zap_pmd_range mm/memory.c:1736 [inline] zap_pud_range mm/memory.c:1765 [inline] zap_p4d_range mm/memory.c:1786 [inline] unmap_page_range+0x3818/0x42c0 mm/memory.c:1807 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1897 exit_mmap+0x264/0xc80 mm/mmap.c:3412 __mmput+0x115/0x390 kernel/fork.c:1345 vhost_detach_mm drivers/vhost/vhost.c:614 [inline] vhost_dev_cleanup+0xa78/0xba0 drivers/vhost/vhost.c:1052 vhost_vsock_dev_release+0x3a9/0x410 drivers/vhost/vsock.c:754 __fput+0x23f/0x880 fs/file_table.c:431 task_work_run+0x24f/0x310 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x27f0 kernel/exit.c:882 do_group_exit+0x207/0x2c0 kernel/exit.c:1031 get_signal+0x16a3/0x1740 kernel/signal.c:2917 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 __do_fast_syscall_32+0xc4/0x110 arch/x86/entry/common.c:389 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf741d579 RSP: 002b:00000000f570656c EFLAGS: 00000206 ORIG_RAX: 00000000000000ac RAX: 0000000000000000 RBX: 000000000000003e RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 8723 jiffies! g129793 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:25584 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 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:blk_flush_plug include/linux/blkdev.h:1035 [inline] RIP: 0010:sched_submit_work kernel/sched/core.c:6585 [inline] RIP: 0010:schedule+0x109/0x320 kernel/sched/core.c:6620 Code: eb 08 48 89 ef e8 f7 0f 97 f5 4c 8d bd 78 12 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ff e8 fa 49 35 f6 49 8b 3f <48> 85 ff 74 0a be 01 00 00 00 e8 a8 a2 cf f8 48 c7 c7 40 55 7f 8e RSP: 0018:ffffc90000167b68 EFLAGS: 00000246 RAX: 1ffff11003adc24f RBX: 0000000000000001 RCX: c8588da64c4faa00 RDX: dffffc0000000000 RSI: ffffffff8c0aea60 RDI: 0000000000000000 RBP: ffff88801d6e0000 R08: ffffffff94236857 R09: 1ffffffff2846d0a R10: dffffc0000000000 R11: fffffbfff2846d0b R12: dffffc0000000000 R13: 1ffff9200002cf74 R14: ffffffff8bc5d3e0 R15: ffff88801d6e1278 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 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: 0 Comm: swapper/1 Not tainted 6.11.0-syzkaller-04557-g2f27fce67173 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:rol32 include/linux/bitops.h:127 [inline] RIP: 0010:jhash2 include/linux/jhash.h:129 [inline] RIP: 0010:hash_stack lib/stackdepot.c:514 [inline] RIP: 0010:stack_depot_save_flags+0x84/0x830 lib/stackdepot.c:614 Code: 04 72 75 44 89 f3 44 89 f0 4c 8b 44 24 08 4c 89 c2 03 02 03 5a 04 44 03 72 08 44 89 f7 c1 c7 04 44 29 f0 31 c7 41 01 de 29 fb <89> fd c1 c5 06 31 dd 44 01 f7 89 e9 c1 c1 08 41 29 ee 44 31 f1 01 RSP: 0018:ffffc90000a17ca0 EFLAGS: 00000212 RAX: 00000000ca6b51b1 RBX: 0000000015453fdf RCX: 00000000d43bcd99 RDX: ffffc90000a17d18 RSI: 0000000000000024 RDI: 000000009ffb4a8d RBP: 00000000951ac294 R08: ffffc90000a17d00 R09: 0000000000000015 R10: ffffc90000a17bd0 R11: ffffffff817f7a90 R12: ffffffff898e5b10 R13: 1ffff92000142ff8 R14: 000000007a998c1f R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f718a30c290 CR3: 00000000673f0000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kasan_save_stack+0x4f/0x60 mm/kasan/common.c:48 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 __call_rcu_common kernel/rcu/tree.c:3106 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210 refdst_drop include/net/dst.h:263 [inline] skb_dst_drop include/net/dst.h:275 [inline] skb_release_head_state+0x73/0x250 net/core/skbuff.c:1174 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] consume_skb+0x60/0xf0 net/core/skbuff.c:1436 nft_synproxy_eval_v4+0x3d2/0x610 net/netfilter/nft_synproxy.c:60 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 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 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5662 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcb/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 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:1037 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037 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 80 d4 03 00 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d 15 de ac 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:ffffc900001a7d08 EFLAGS: 00000246 RAX: ffff88801d6f8000 RBX: ffff88801e286864 RCX: 00000000002e4f41 RDX: 0000000000000001 RSI: ffff88801e286800 RDI: ffff88801e286864 RBP: 000000000003a678 R08: ffff8880b8937c7b R09: 1ffff11017126f8f R10: dffffc0000000000 R11: ffffffff8bbd8940 R12: ffff88801e3ed000 R13: 0000000000000001 R14: 0000000000000001 R15: ffffffff8f11bb40 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 start_secondary+0x102/0x110 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x147