rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5843/1:b..l rcu: (detected by 1, t=10503 jiffies, g=15717, q=1544743 ncpus=2) task:syz-executor state:R running task stack:19936 pid:5843 tgid:5843 ppid:5822 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 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:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:write_comp_data kernel/kcov.c:245 [inline] RIP: 0010:__sanitizer_cov_trace_cmp4+0x8/0x90 kernel/kcov.c:288 Code: 44 0a 20 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 <65> 48 8b 14 25 c0 d5 03 00 65 8b 05 80 51 64 7e 25 00 01 ff 00 74 RSP: 0018:ffffc9000416fac0 EFLAGS: 00000293 RAX: ffffffff820f4858 RBX: 0000000000000008 RCX: ffff88802750da00 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000005 RBP: 00000000000016d3 R08: ffffffff820f4866 R09: 1ffff11003aac358 R10: dffffc0000000000 R11: ffffed1003aac359 R12: 0000000000000005 R13: dffffc0000000000 R14: ffff88801d561b04 R15: ffff88801d561b10 __update_page_owner_free_handle mm/page_owner.c:268 [inline] __reset_page_owner+0x126/0x430 mm/page_owner.c:298 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xd3f/0x1010 mm/page_alloc.c:2659 discard_slab mm/slub.c:2688 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3157 put_cpu_partial+0x17c/0x250 mm/slub.c:3232 __slab_free+0x290/0x380 mm/slub.c:4483 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:250 [inline] slab_post_alloc_hook mm/slub.c:4119 [inline] slab_alloc_node mm/slub.c:4168 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4175 getname_flags+0xb7/0x540 fs/namei.c:139 user_path_at+0x24/0x60 fs/namei.c:3069 ksys_umount fs/namespace.c:2031 [inline] __do_sys_umount fs/namespace.c:2039 [inline] __se_sys_umount fs/namespace.c:2037 [inline] __x64_sys_umount+0xf1/0x170 fs/namespace.c:2037 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: 0033:0x7f1c38b87057 RSP: 002b:00007ffdf2fe0748 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 00007f1c38c018f4 RCX: 00007f1c38b87057 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdf2fe0800 RBP: 00007ffdf2fe0800 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdf2fe1880 R13: 00007f1c38c018f4 R14: 00007ffdf2fe18c0 R15: 0000000000000047 rcu: rcu_preempt kthread starved for 1540 jiffies! g15717 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:26264 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 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: CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.13.0-rc7-syzkaller-01131-g8d20dcda404d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:in_task_stack+0x0/0x40 arch/x86/kernel/dumpstack.c:34 Code: 00 48 c7 c7 c0 61 76 8e 4c 89 fe e8 3a 5e 2e f9 e9 51 ff ff ff 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <66> 0f 1f 00 48 8b 4e 20 48 8d b1 00 80 00 00 48 39 f9 41 0f 96 c0 RSP: 0018:ffffc900001e6570 EFLAGS: 00000282 RAX: 1ffff9200003cccf RBX: ffff88801cee8000 RCX: ffffc900001e6660 RDX: ffffc900001e6640 RSI: ffff88801cee8000 RDI: ffffc900001e65e0 RBP: ffffc900001e65e0 R08: ffffc900001e669f R09: 0000000000000000 R10: ffffc900001e6640 R11: fffff5200003ccd4 R12: ffffc900001e6640 R13: ffffc900001e6668 R14: ffffc900001e6660 R15: 1ffff9200003cccd FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f32ee5452d8 CR3: 000000005ff4c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: get_stack_info_noinstr+0x1a/0x130 arch/x86/kernel/dumpstack_64.c:173 get_stack_info+0x3c/0xf0 arch/x86/kernel/dumpstack_64.c:199 __unwind_start+0x434/0x740 arch/x86/kernel/unwind_orc.c:729 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 ref_tracker_alloc+0x188/0x490 lib/ref_tracker.c:209 __netdev_tracker_alloc include/linux/netdevice.h:4266 [inline] netdev_hold include/linux/netdevice.h:4295 [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:1626 [inline] __mkroute_output net/ipv4/route.c:2620 [inline] ip_route_output_key_hash_rcu+0x13cc/0x2390 net/ipv4/route.c:2842 ip_route_output_key_hash+0x193/0x2b0 net/ipv4/route.c:2671 __ip_route_output_key include/net/route.h:169 [inline] ip_route_output_flow+0x29/0x140 net/ipv4/route.c:2899 ip_route_output_key include/net/route.h:179 [inline] ip_route_me_harder+0x877/0x1360 net/ipv4/netfilter.c:53 synproxy_send_tcp+0x356/0x6c0 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x8a4/0xe20 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+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:5837 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5950 process_backlog+0x662/0x15b0 net/core/dev.c:6298 __napi_poll+0xcb/0x490 net/core/dev.c:7115 napi_poll net/core/dev.c:7184 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7306 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 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