rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6488/1:b..l rcu: (detected by 1, t=10503 jiffies, g=12221, q=774 ncpus=2) task:syz.2.408 state:R running task stack:23808 pid:6488 tgid:6488 ppid:5235 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:stack_trace_consume_entry+0x3b/0x280 kernel/stacktrace.c:86 Code: 18 48 89 fb 48 ba 00 00 00 00 00 fc ff df 4c 8d 4f 10 4d 89 cf 49 c1 ef 03 41 0f b6 04 17 84 c0 0f 85 06 01 00 00 44 8b 43 10 <48> 8d 6b 08 49 89 ec 49 c1 ec 03 41 0f b6 04 14 84 c0 0f 85 1a 01 RSP: 0018:ffffc900163ef050 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc900163ef180 RCX: ffffffff917bb000 RDX: dffffc0000000000 RSI: ffffffff81e94a1a RDI: ffffc900163ef180 RBP: ffffc900163ef130 R08: 000000000000000b R09: ffffc900163ef190 R10: ffffc900163ef0f0 R11: ffffffff8180a0e0 R12: ffff88802e9a9e00 R13: ffffffff8180a0e0 R14: ffffc900163ef180 R15: 1ffff92002c7de32 arch_stack_walk+0x10e/0x150 arch/x86/kernel/stacktrace.c:27 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 __slab_free+0x31b/0x3d0 mm/slub.c:4490 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+0x153a/0x1a80 mm/vma.c:1433 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: 0033:0x7f656ad7e0b7 RSP: 002b:00007ffecd161248 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f656bbc96c0 RCX: 00007f656ad7e0b7 RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007f656bbaa000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000021000 R11: 0000000000000206 R12: 00007ffecd1613a0 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10324 jiffies! g12221 f0x0 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:25888 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: 5284 Comm: kworker/0:7 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:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:preempt_count_sub+0x3b/0x170 kernel/sched/core.c:5817 Code: c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30 84 c0 0f 85 d0 00 00 00 83 3d 5e ab d9 18 00 75 22 65 8b 05 dd 99 a0 7e <89> c1 81 e1 ff ff ff 7f 39 d9 7c 27 81 fb fe 00 00 00 77 07 0f b6 RSP: 0018:ffffc90000006a18 EFLAGS: 00000246 RAX: 0000000080000103 RBX: 0000000000000001 RCX: ffffffff9a3ce903 RDX: dffffc0000000000 RSI: ffffc90000000000 RDI: 0000000000000001 RBP: ffffc90000006b00 R08: ffffc90000006f70 R09: 0000000000000000 R10: ffffc90000006b50 R11: fffff52000000d6c R12: dffffc0000000000 R13: ffffc90000006b00 R14: dffffc0000000000 R15: ffffc90000006f80 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1d37c87440 CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x18e6/0x22d0 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_node_track_caller_noprof+0x225/0x440 mm/slub.c:4283 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1322 [inline] synproxy_send_client_synack+0x1ba/0xf30 net/netfilter/nf_synproxy_core.c:460 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59 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: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