rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4693/1:b..l P3668/1:b..l P5059/1:b..l (detected by 1, t=10502 jiffies, g=13933, q=138) task:syz.2.417 state:R running task stack:27064 pid: 5059 ppid: 3567 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:403 [inline] filemap_map_pages+0x122d/0x15c0 mm/filemap.c:3353 do_fault_around mm/memory.c:4213 [inline] do_read_fault mm/memory.c:4228 [inline] do_fault mm/memory.c:4362 [inline] handle_pte_fault mm/memory.c:4621 [inline] __handle_mm_fault mm/memory.c:4756 [inline] handle_mm_fault+0x341b/0x5950 mm/memory.c:4854 do_user_addr_fault arch/x86/mm/fault.c:1357 [inline] handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x271/0x700 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x7f9c014bfc36 RSP: 002b:00007fff03648f70 EFLAGS: 00010202 RAX: 000000110c43c000 RBX: 00007f9c022ac720 RCX: 0000000000000006 RDX: ffffffff87a856f1 RSI: 000000000000215b RDI: 0000000000000040 RBP: 0000000000000001 R08: 00007f9c01767000 R09: 00007f9c01769000 R10: 0000000087a856f5 R11: 000000000000001d R12: ffffffff87a8510c R13: 00007f9c0177d0f0 R14: 0000000000000008 R15: 000000000000260c task:kworker/0:10 state:R running task stack:23736 pid: 3668 ppid: 2 flags:0x00004000 Workqueue: events_power_efficient gc_worker Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 RIP: 0010:__rcu_read_lock+0x4c/0xb0 kernel/rcu/tree_plugin.h:400 Code: 48 c1 eb 03 42 0f b6 04 33 84 c0 75 2f 41 8b 2f ff c5 42 0f b6 04 33 84 c0 75 38 41 89 2f 42 0f b6 04 33 84 c0 75 43 41 8b 07 <3d> 00 00 00 40 7d 07 5b 41 5e 41 5f 5d c3 0f 0b eb f5 44 89 f9 80 RSP: 0018:ffffc90002ee7ad8 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 1ffff11003d3a7f7 RCX: ffff88801e9d3b80 RDX: 0000000000000000 RSI: 000000000000e49f RDI: 0000000000040000 RBP: 0000000000000001 R08: ffffffff88909a4e R09: fffffbfff1bd2a56 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff91830660 R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88801e9d3fbc rcu_read_lock include/linux/rcupdate.h:737 [inline] gc_worker+0x284/0x14b0 net/netfilter/nf_conntrack_core.c:1470 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 task:syz.4.216 state:R running task stack:24768 pid: 4693 ppid: 4346 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194 bpf_lru_pop_free+0x194c/0x1c20 prealloc_lru_pop kernel/bpf/hashtab.c:303 [inline] __htab_lru_percpu_map_update_elem+0x18a/0x840 kernel/bpf/hashtab.c:1289 bpf_percpu_hash_update+0xf2/0x1c0 kernel/bpf/hashtab.c:2237 bpf_map_update_value+0x268/0x6c0 kernel/bpf/syscall.c:196 generic_map_update_batch+0x54d/0x8b0 kernel/bpf/syscall.c:1421 bpf_map_do_batch+0x4d0/0x620 __sys_bpf+0x55c/0x670 __do_sys_bpf kernel/bpf/syscall.c:4755 [inline] __se_sys_bpf kernel/bpf/syscall.c:4753 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4753 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f5fd5eece79 RSP: 002b:00007f5fd4348038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f5fd6089058 RCX: 00007f5fd5eece79 RDX: 0000000000000038 RSI: 00000000200003c0 RDI: 000000000000001a RBP: 00007f5fd5f5a916 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5fd6089058 R15: 00007ffe3c3bced8 rcu: rcu_preempt kthread starved for 10567 jiffies! g13933 f0x0 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:26168 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 5067 Comm: syz.0.418 Not tainted 5.15.165-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619 update_process_times+0x196/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1686 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:lock_acquire+0x145/0x4f0 Code: 8b 1d af c1 9f 7e 48 81 c3 ec 0a 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 c4 02 00 00 83 3b 00 0f 85 5c 01 00 00 <4c> 8d bc 24 80 00 00 00 4c 89 fb 48 c1 eb 03 42 80 3c 2b 00 74 08 RSP: 0018:ffffc90002317ba0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880233b28ac RCX: ffffffff8162adbc RDX: 0000000000000000 RSI: ffffffff8ad8f7a0 RDI: ffffffff8ad8f760 RBP: ffffc90002317ce8 R08: dffffc0000000000 R09: fffffbfff1bd2a56 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000462f7c R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff8ad8bc20 __might_fault+0xb4/0x110 mm/memory.c:5328 _copy_from_user+0x28/0x170 lib/usercopy.c:14 copy_from_user include/linux/uaccess.h:192 [inline] restore_altstack+0x9a/0x400 kernel/signal.c:4249 __do_sys_rt_sigreturn+0x19d/0x250 arch/x86/kernel/signal.c:677 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f0b2e196e79 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd18e4a7f8 EFLAGS: 00000246 RAX: fffffffffffffffc RBX: 00000000000208be RCX: 00007f0b2e196e79 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0b2e333064 RBP: 00007f0b2e333064 R08: 00007f0b2e332f80 R09: 00007ffd18e4aadf R10: 00007ffd18e4a8f0 R11: 0000000000000246 R12: 0000000000000032 R13: 00007ffd18e4a8f0 R14: 00007ffd18e4a910 R15: 000000000002088c