rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5750/1:b..l rcu: (detected by 1, t=10502 jiffies, g=9793, q=741548 ncpus=2) task:syz.0.154 state:R running task stack:23808 pid:5750 tgid:5750 ppid:5232 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7004 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:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5829 Code: 2b 00 74 08 4c 89 f7 e8 3a 40 8e 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900162af160 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92002c55e38 RCX: 9ae4eb174c7e4700 RDX: dffffc0000000000 RSI: ffffffff8c0adc40 RDI: ffffffff8c60fb20 RBP: ffffc900162af2c0 R08: ffffffff942c7807 R09: 1ffffffff2858f00 R10: dffffc0000000000 R11: fffffbfff2858f01 R12: 1ffff92002c55e34 R13: dffffc0000000000 R14: ffffc900162af1c0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 __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:1109 [inline] free_unref_page+0xd0f/0xf20 mm/page_alloc.c:2638 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] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141 mt_alloc_one lib/maple_tree.c:162 [inline] mas_alloc_nodes+0x26c/0x840 lib/maple_tree.c:1241 mas_node_count_gfp lib/maple_tree.c:1321 [inline] mas_preallocate+0x554/0x8c0 lib/maple_tree.c:5546 vma_iter_prealloc mm/vma.h:432 [inline] __split_vma+0x302/0xc50 mm/vma.c:397 split_vma mm/vma.c:460 [inline] vma_modify+0x141c/0x1a80 mm/vma.c:1425 vma_modify_flags+0x3a9/0x420 mm/vma.c:1451 mprotect_fixup+0x45a/0xaa0 mm/mprotect.c:664 do_mprotect_pkey+0x8e0/0xd80 mm/mprotect.c:838 __do_sys_mprotect mm/mprotect.c:859 [inline] __se_sys_mprotect mm/mprotect.c:856 [inline] __x64_sys_mprotect+0x80/0x90 mm/mprotect.c:856 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: 0033:0x7fe03c77e0b7 RSP: 002b:00007ffe95eb5ec8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007fe03d5d66c0 RCX: 00007fe03c77e0b7 RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007fe03d5b7000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000021000 R11: 0000000000000206 R12: 00007ffe95eb6020 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10473 jiffies! g9793 f0x2 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:25744 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8 Comm: kworker/0:0 Not tainted 6.12.0-rc2-syzkaller-00220-g25c12b459db8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:__asan_memset+0x16/0x50 mm/kasan/shadow.c:84 Code: 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 41 89 f6 48 89 fd 48 8b 4c 24 18 <48> 89 d6 ba 01 00 00 00 e8 fd e5 ff ff 84 c0 74 12 48 89 ef 44 89 RSP: 0018:ffffc90000007120 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000028 RCX: ffffffff89e7ae46 RDX: 0000000000000028 RSI: 0000000000000000 RDI: ffffc900000071a0 RBP: ffffc900000071a0 R08: ffffffff89f857e9 R09: ffffffff89dab9b3 R10: 0000000000000002 R11: ffff88801beeda00 R12: ffffc900000071a0 R13: 0000000000000014 R14: 0000000000000000 R15: ffff88820cabe8c0 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcd3c7283c CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: synproxy_parse_options+0xc6/0x8d0 net/netfilter/nf_synproxy_core.c:32 nft_synproxy_do_eval+0x2ee/0xa60 net/netfilter/nft_synproxy.c:134 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: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