rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=57e4/1/0x4000000000000000 softirq=24384/24385 fqs=2 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5126/1:b..l rcu: (detected by 1, t=10502 jiffies, g=32621, q=373 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 10425 Comm: syz-executor.0 Not tainted 6.2.0-syzkaller-10217-ga93e884edf61 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 RIP: 0010:rcu_lockdep_current_cpu_online+0xb/0x140 kernel/rcu/tree.c:4071 Code: de 02 e9 d8 fe ff ff e8 c3 74 68 00 e9 5c ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 65 8b 15 1d e9 95 7e <81> e2 00 00 f0 00 b8 01 00 00 00 75 0a 8b 15 e6 0a 0a 0d 85 d2 75 RSP: 0018:ffffc90000007d30 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000003 RCX: ffffffff81661b39 RDX: 0000000000010002 RSI: 0000000000010003 RDI: ffffffff8c113900 RBP: 1ffff92000000fab R08: 0000000000000000 R09: ffffffff8e77d957 R10: fffffbfff1cefb2a R11: 0000000000000000 R12: 0000000000000001 R13: ffff8880b982b900 R14: 0000000000000000 R15: ffff88803e13b340 FS: 0000555556e99400(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff1f02d9768 CR3: 000000007bdda000 CR4: 0000000000350ef0 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:112 [inline] rcu_read_lock_held_common kernel/rcu/update.c:102 [inline] rcu_read_lock_sched_held+0x29/0x70 kernel/rcu/update.c:123 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x5b3/0x780 kernel/locking/lockdep.c:5680 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x1a/0x70 kernel/locking/spinlock.c:194 __run_hrtimer kernel/time/hrtimer.c:1681 [inline] __hrtimer_run_queues+0x578/0x1010 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x320/0x7b0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1096 [inline] __sysvec_apic_timer_interrupt+0x180/0x660 arch/x86/kernel/apic/apic.c:1113 sysvec_apic_timer_interrupt+0x92/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__x64_sys_chdir+0x4/0x260 fs/open.c:509 Code: e9 a1 ad ff ff e8 dc 22 f2 ff eb c6 48 89 14 24 e8 d1 22 f2 ff 48 8b 14 24 eb d6 66 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <41> 57 41 56 41 55 41 54 55 48 bd 00 00 00 00 00 fc ff df 53 48 89 RSP: 0018:ffffc900066fff38 EFLAGS: 00000206 RAX: 0000000000000050 RBX: 0000000000000000 RCX: 1ffffffff1cef521 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: ffffc900066fff58 RBP: ffffc900066fff48 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff1cefb2a R11: 0000000000000000 R12: ffffc900066fff58 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7ff1ef68b267 Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 50 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc693b8c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000050 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff1ef68b267 RDX: 0000000000000001 RSI: 00007ff1ef787ef0 RDI: 00007ffc693b8ce0 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ff1ef787ef0 R10: 0000555556e99400 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffc693b8d20 task:syz-executor.2 state:R running task stack:24216 pid:5126 ppid:5104 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5304 [inline] __schedule+0xcce/0x5b20 kernel/sched/core.c:6622 preempt_schedule_irq+0x52/0x90 kernel/sched/core.c:6934 irqentry_exit+0x35/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__rcu_read_lock+0xa6/0xf0 kernel/rcu/tree_plugin.h:402 Code: d2 75 58 48 b8 00 00 00 00 00 fc ff df 89 9d 3c 04 00 00 65 48 8b 1c 25 80 b8 03 00 48 8d bb 3c 04 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 15 8b RSP: 0018:ffffc9000460f6b8 EFLAGS: 00000213 RAX: dffffc0000000000 RBX: ffff888025cb57c0 RCX: 0000000000000000 RDX: 1ffff11004b96b7f RSI: ffffffff81927c80 RDI: ffff888025cb5bfc RBP: ffff888025cb57c0 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000080000000 R11: 0000000000094001 R12: ffffc9000460f7e8 R13: 0000000000000000 R14: ffff888025cb57c0 R15: 00000000000000c0 rcu_read_lock include/linux/rcupdate.h:771 [inline] is_bpf_text_address+0x15/0x1b0 kernel/bpf/core.c:719 kernel_text_address kernel/extable.c:125 [inline] kernel_text_address+0x3d/0x80 kernel/extable.c:94 __kernel_text_address+0xd/0x30 kernel/extable.c:79 unwind_get_return_address arch/x86/kernel/unwind_orc.c:342 [inline] unwind_get_return_address+0x55/0xa0 arch/x86/kernel/unwind_orc.c:337 arch_stack_walk+0x97/0xf0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x90/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:769 [inline] slab_alloc_node mm/slub.c:3452 [inline] slab_alloc mm/slub.c:3460 [inline] __kmem_cache_alloc_lru mm/slub.c:3467 [inline] kmem_cache_alloc+0x175/0x320 mm/slub.c:3476 prepare_creds+0x43/0x7d0 kernel/cred.c:260 copy_creds+0xa7/0xe70 kernel/cred.c:365 copy_process+0xdae/0x76c0 kernel/fork.c:2129 kernel_clone+0xeb/0xa10 kernel/fork.c:2684 __do_sys_clone+0xba/0x100 kernel/fork.c:2825 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f3f64489e2b RSP: 002b:00007ffc4b756c10 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3f64489e2b RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000555557131400 R10: 00005555571316d0 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffc4b756cf0 rcu: rcu_preempt kthread starved for 10498 jiffies! g32621 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:28672 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5304 [inline] __schedule+0xcce/0x5b20 kernel/sched/core.c:6622 schedule+0xde/0x1a0 kernel/sched/core.c:6698 schedule_timeout+0x14e/0x2b0 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1608 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1807 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 51 Comm: kworker/u4:3 Not tainted 6.2.0-syzkaller-10217-ga93e884edf61 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline] RIP: 0010:smp_call_function_many_cond+0x444/0x10a0 kernel/smp.c:987 Code: 00 45 85 e4 74 48 48 8b 04 24 49 89 c5 83 e0 07 49 c1 ed 03 49 89 c4 4d 01 fd 41 83 c4 03 e8 13 3d 0b 00 f3 90 41 0f b6 45 00 <41> 38 c4 7c 08 84 c0 0f 85 4e 0a 00 00 8b 43 08 31 ff 83 e0 01 41 RSP: 0018:ffffc90000bc7950 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9844e60 RCX: 0000000000000000 RDX: ffff88801807ba80 RSI: ffffffff81798b5d RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003 R13: ffffed10173089cd R14: 0000000000000001 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555751d708 CR3: 000000000c572000 CR4: 0000000000350ee0 Call Trace: on_each_cpu_cond_mask+0x5a/0xa0 kernel/smp.c:1155 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1770 [inline] text_poke_bp_batch+0x237/0x770 arch/x86/kernel/alternative.c:1970 text_poke_flush arch/x86/kernel/alternative.c:2161 [inline] text_poke_flush arch/x86/kernel/alternative.c:2158 [inline] text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:2168 arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32f/0x410 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b5/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:799 [inline] toggle_allocation_gate+0xf8/0x230 mm/kfence/core.c:791 process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308