rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5778/1:b..l P5768/2:b..l rcu: (detected by 1, t=10503 jiffies, g=9321, q=866 ncpus=2) task:syz.1.137 state:R running task stack:23168 pid:5768 tgid:5766 ppid:5230 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6997 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:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216 Code: 8b 3d 14 2d 9d 0c 48 89 de 5b e9 f3 c9 5d 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 c0 d7 03 00 65 8b 15 70 22 6f 7e 81 e2 00 01 ff 00 RSP: 0018:ffffc9000d877170 EFLAGS: 00000246 RAX: ffffffff81cdcaa8 RBX: 1ffffd40003f4980 RCX: ffff88807df6da00 RDX: ffff88807df6da00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff81cdca94 R09: 1ffffd40003f4980 R10: dffffc0000000000 R11: fffff940003f4981 R12: ffffc9000d877340 R13: ffffea0001fa4c08 R14: ffffea0001fa4c00 R15: 1ffffd40003f4981 arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] page_fixed_fake_head include/linux/page-flags.h:205 [inline] page_is_fake_head include/linux/page-flags.h:237 [inline] PageTail include/linux/page-flags.h:281 [inline] const_folio_flags include/linux/page-flags.h:309 [inline] folio_test_uptodate include/linux/page-flags.h:763 [inline] next_uptodate_folio+0x3a8/0xa40 mm/filemap.c:3512 filemap_map_pages+0x2f3/0x20d0 mm/filemap.c:3641 do_fault_around mm/memory.c:5240 [inline] do_read_fault mm/memory.c:5273 [inline] do_fault mm/memory.c:5416 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x2b98/0x6800 mm/memory.c:5751 __handle_mm_fault mm/memory.c:5894 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6062 faultin_page mm/gup.c:1187 [inline] __get_user_pages+0x1b16/0x48d0 mm/gup.c:1485 populate_vma_page_range+0x264/0x330 mm/gup.c:1923 __mm_populate+0x27a/0x460 mm/gup.c:2026 mm_populate include/linux/mm.h:3371 [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: 0033:0x7ff8ae37dff9 RSP: 002b:00007ff8addff038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ff8ae535f80 RCX: 00007ff8ae37dff9 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007ff8ae3f0296 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff8ae535f80 R15: 00007ffe63d3a138 task:syz.0.141 state:R running task stack:23168 pid:5778 tgid:5777 ppid:5225 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6854 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6878 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] finish_fault+0xb7f/0x1480 mm/memory.c:5152 do_read_fault mm/memory.c:5286 [inline] do_fault mm/memory.c:5416 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x2d44/0x6800 mm/memory.c:5751 __handle_mm_fault mm/memory.c:5894 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6062 faultin_page mm/gup.c:1187 [inline] __get_user_pages+0x1b16/0x48d0 mm/gup.c:1485 populate_vma_page_range+0x264/0x330 mm/gup.c:1923 __mm_populate+0x27a/0x460 mm/gup.c:2026 mm_populate include/linux/mm.h:3371 [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: 0033:0x7f5aa817dff9 RSP: 002b:00007f5aa8fb2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f5aa8335f80 RCX: 00007f5aa817dff9 RDX: 000000000000000c RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007f5aa81f0296 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5aa8335f80 R15: 00007ffe210aec08 rcu: rcu_preempt kthread starved for 9703 jiffies! g9321 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:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 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: 16 Comm: ksoftirqd/0 Not tainted 6.11.0-syzkaller-11503-gd505d3593b52 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:lock_release+0x658/0xa30 kernel/locking/lockdep.c:5847 Code: 3c 3b 00 74 08 4c 89 f7 e8 95 24 8e 00 f6 84 24 91 00 00 00 02 75 77 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90000156e80 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200002ade2 RCX: ffffc90000156f03 RDX: 0000000000000002 RSI: ffffffff8c0adbc0 RDI: ffffffff8c6100e0 RBP: ffffc90000156fc0 R08: ffffffff901cf8af R09: 1ffffffff2039f15 R10: dffffc0000000000 R11: fffffbfff2039f16 R12: 1ffff9200002addc R13: 0000000000000246 R14: ffffc90000156f10 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000040 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] net_generic include/net/netns/generic.h:48 [inline] synproxy_pernet+0x202/0x270 include/net/netfilter/nf_synproxy.h:32 nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:84 [inline] nft_synproxy_do_eval+0x470/0xa60 net/netfilter/nft_synproxy.c:145 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+0x1ea/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 run_ksoftirqd+0xca/0x130 kernel/softirq.c:927 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