sched: DL replenish lagged too much rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5729/1:b..l P6151/1:b..l P5686/1:b..l rcu: (detected by 1, t=10503 jiffies, g=16309, q=2392590 ncpus=2) task:syz-executor state:R running task stack:20992 pid:5686 tgid:5686 ppid:5663 flags:0x00000000 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] copy_pte_range mm/memory.c:1195 [inline] copy_pmd_range+0x7b90/0x85f0 mm/memory.c:1256 copy_pud_range mm/memory.c:1293 [inline] copy_p4d_range mm/memory.c:1317 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1415 dup_mmap kernel/fork.c:750 [inline] dup_mm kernel/fork.c:1674 [inline] copy_mm+0x11fb/0x1f40 kernel/fork.c:1723 copy_process+0x1845/0x3d50 kernel/fork.c:2372 kernel_clone+0x226/0x8f0 kernel/fork.c:2784 __do_sys_clone kernel/fork.c:2927 [inline] __se_sys_clone kernel/fork.c:2911 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2911 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: 0033:0x7f6d5f774753 RSP: 002b:00007ffe4f96b0a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6d5f774753 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 000055555ea457d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000212a8 R14: 0000000000020856 R15: 00007ffe4f96b230 task:syz.2.164 state:R running task stack:23680 pid:6151 tgid:6150 ppid:5649 flags:0x00000002 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 __local_bh_enable_ip+0x179/0x200 kernel/softirq.c:389 tun_rx_batched+0x732/0x8f0 tun_get_user+0x3056/0x47e0 drivers/net/tun.c:2007 tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2053 new_sync_write fs/read_write.c:590 [inline] vfs_write+0xa6d/0xc90 fs/read_write.c:683 ksys_write+0x183/0x2b0 fs/read_write.c:736 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: 0033:0x7f1849f7c9df RSP: 002b:00007f184acca000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f184a135f80 RCX: 00007f1849f7c9df RDX: 000000000000003a RSI: 0000000020000440 RDI: 00000000000000c8 RBP: 00007f1849ff0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000003a R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f184a135f80 R15: 00007ffe49985898 task:syz-executor state:R running task stack:20992 pid:5729 tgid:5729 ppid:5724 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:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5829 Code: 2b 00 74 08 4c 89 f7 e8 3a 64 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:ffffc90003c7f2e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200078fe68 RCX: 78cac7bdc8a1bc00 RDX: dffffc0000000000 RSI: ffffffff8c0adca0 RDI: ffffffff8c610a60 RBP: ffffc90003c7f430 R08: ffffffff942c7807 R09: 1ffffffff2858f00 R10: dffffc0000000000 R11: fffffbfff2858f01 R12: 1ffff9200078fe64 R13: dffffc0000000000 R14: ffffc90003c7f340 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] percpu_ref_put_many include/linux/percpu-refcount.h:330 [inline] percpu_ref_put+0x36/0x180 include/linux/percpu-refcount.h:351 __mem_cgroup_uncharge_folios+0xdf/0x1c0 mm/memcontrol.c:4708 mem_cgroup_uncharge_folios include/linux/memcontrol.h:725 [inline] folios_put_refs+0x764/0x860 mm/swap.c:1006 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x64c/0x1cf0 mm/shmem.c:1032 shmem_truncate_range mm/shmem.c:1144 [inline] shmem_evict_inode+0x29b/0xa80 mm/shmem.c:1272 evict+0x4e8/0x9b0 fs/inode.c:806 __dentry_kill+0x20d/0x630 fs/dcache.c:615 dput+0x19f/0x2b0 fs/dcache.c:857 __fput+0x5d2/0x880 fs/file_table.c:439 task_work_run+0x24f/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd5bc77cb8a RSP: 002b:00007ffc711b1690 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fd5bc77cb8a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffc711b16dc R08: 0000000000000000 R09: 00007ffc711b13f7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 0000000000020e37 R14: 00000000000202de R15: 00007ffc711b1730 rcu: rcu_preempt kthread starved for 10586 jiffies! g16309 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:24912 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+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: 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 6.11.0-next-20240924-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:synproxy_send_client_synack+0x592/0xf30 net/netfilter/nf_synproxy_core.c:474 Code: 85 f5 06 00 00 41 8b 1c 24 0f cb ff c3 0f cb 49 8d 7d 08 48 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 fc 06 00 00 41 89 5d 08 <4d> 8d 75 0c 4d 89 f7 49 c1 ef 03 41 0f b6 04 17 84 c0 0f 85 04 07 RSP: 0018:ffffc90000007060 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 000000002870292c RCX: 0000000000225c0b RDX: dffffc0000000000 RSI: 57ea41c1b1cab550 RDI: ffff8881ada4515c RBP: ffffc90000007170 R08: ffffffff8a4c01b8 R09: 1ffff11035b48a5c R10: dffffc0000000000 R11: ffffed1035b48a5d R12: ffff8881ada44958 R13: ffff8881ada45154 R14: ffff8881ada45158 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6d604656c0 CR3: 000000000e734000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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:5662 [inline] __netif_receive_skb+0x2bf/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 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