rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15658/3:b..l rcu: (detected by 0, t=10503 jiffies, g=145321, q=1957778 ncpus=2) task:syz.1.1478 state:R running task stack:23776 pid:15658 tgid:15655 ppid:15234 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1893/0x4b50 kernel/sched/core.c:6607 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6929 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:5826 Code: 2b 00 74 08 4c 89 f7 e8 fa 22 8c 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:ffffc900040370e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000806e28 RCX: e27b9cd3a9c2d300 RDX: dffffc0000000000 RSI: ffffffff8c0ae940 RDI: ffffffff8c60e0c0 RBP: ffffc90004037228 R08: ffffffff9424f787 R09: 1ffffffff2849ef0 R10: dffffc0000000000 R11: fffffbfff2849ef1 R12: 1ffff92000806e24 R13: dffffc0000000000 R14: ffffc90004037140 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ref_add_unless include/linux/page_ref.h:235 [inline] folio_ref_add_unless include/linux/page_ref.h:248 [inline] folio_try_get+0x3b/0x350 include/linux/page_ref.h:264 next_uptodate_folio+0x164/0xa40 mm/filemap.c:3487 filemap_map_pages+0x2f6/0x1ec0 mm/filemap.c:3627 do_fault_around mm/memory.c:5034 [inline] do_read_fault mm/memory.c:5067 [inline] do_fault mm/memory.c:5206 [inline] do_pte_missing mm/memory.c:3962 [inline] handle_pte_fault+0x30a6/0x7010 mm/memory.c:5536 __handle_mm_fault mm/memory.c:5679 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:5847 faultin_page mm/gup.c:1207 [inline] __get_user_pages+0x6ec/0x16a0 mm/gup.c:1506 populate_vma_page_range+0x264/0x330 mm/gup.c:1945 __mm_populate+0x27a/0x460 mm/gup.c:2048 mm_populate include/linux/mm.h:3437 [inline] vm_mmap_pgoff+0x2c3/0x3d0 mm/util.c:593 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: 0033:0x7f1d7b97def9 RSP: 002b:00007f1d7c7da038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f1d7bb36058 RCX: 00007f1d7b97def9 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007f1d7b9f0b76 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1d7bb36058 R15: 00007ffcf598e9d8 rcu: rcu_preempt kthread starved for 9631 jiffies! g145321 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:24560 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5264 [inline] __schedule+0x1893/0x4b50 kernel/sched/core.c:6607 __schedule_loop kernel/sched/core.c:6684 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6699 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+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 15584 Comm: kworker/1:5 Not tainted 6.11.0-syzkaller-07462-g1868f9d0260e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:__unwind_start+0x5a4/0x740 Code: 74 08 48 89 df e8 3c eb ba 00 48 8b 44 24 10 48 39 03 0f 87 3b fb ff ff 4c 89 f7 e8 76 d2 ff ff 48 ba 00 00 00 00 00 fc ff df <48> 8b 04 24 0f b6 04 10 84 c0 75 0f 41 83 3e 00 0f 85 5d ff ff ff RSP: 0018:ffffc90000a175a0 EFLAGS: 00000282 RAX: 0000000080000101 RBX: ffffc90000a17638 RCX: 0000000080000102 RDX: dffffc0000000000 RSI: ffffc90000a11000 RDI: 0000000000000001 RBP: 1ffff92000142ec1 R08: ffffc90000a175f0 R09: ffffc90000a17650 R10: dffffc0000000000 R11: fffff52000142ecc R12: 1ffff92000142ec2 R13: ffffc90000a17610 R14: ffffc90000a17600 R15: ffffc90000a17608 FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000006e404000 CR4: 0000000000350ef0 Call Trace: unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe5/0x150 arch/x86/kernel/stacktrace.c:24 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] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4296 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1004 [inline] ref_tracker_alloc+0x14b/0x490 lib/ref_tracker.c:203 __netdev_tracker_alloc include/linux/netdevice.h:4050 [inline] netdev_hold include/linux/netdevice.h:4079 [inline] dst_init+0xee/0x490 net/core/dst.c:52 dst_alloc+0x14f/0x190 net/core/dst.c:93 rt_dst_alloc net/ipv4/route.c:1612 [inline] __mkroute_output net/ipv4/route.c:2573 [inline] ip_route_output_key_hash_rcu+0x13cc/0x2390 net/ipv4/route.c:2795 ip_route_output_key_hash+0x193/0x2b0 net/ipv4/route.c:2624 __ip_route_output_key include/net/route.h:141 [inline] ip_route_output_flow+0x29/0x140 net/ipv4/route.c:2852 ip_route_output_key include/net/route.h:151 [inline] ip_route_me_harder+0x80d/0x1300 net/ipv4/netfilter.c:53 synproxy_send_tcp+0x356/0x6c0 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x8b8/0xf30 net/netfilter/nf_synproxy_core.c:484 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+0x4af/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+0xc5/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a6/0x450 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+0xcd/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+0x2c7/0x980 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+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244