rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=dcf4/1/0x4000000000000000 softirq=45408/45409 fqs=0 rcu: (detected by 0, t=10505 jiffies, g=41089, q=27 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13350 Comm: syz.4.1870 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__raw_spin_lock_irq include/linux/spinlock_api_smp.h:120 [inline] RIP: 0010:_raw_spin_lock_irq+0xd7/0x120 kernel/locking/spinlock.c:170 Code: bf 01 00 00 00 e8 b9 f4 a2 f5 49 8d 7c 24 18 31 f6 31 d2 31 c9 41 b8 01 00 00 00 45 31 c9 ff 75 08 e8 6d 1d b0 f5 48 83 c4 08 <4c> 89 e7 e8 e1 86 b1 f5 48 c7 04 24 0e 36 e0 45 4b c7 04 2f 00 00 RSP: 0018:ffffc90000a18ca0 EFLAGS: 00000096 RAX: 1cab088dc2b2ef00 RBX: 1ffff92000143198 RCX: ffff88807f4264d8 RDX: dffffc0000000000 RSI: ffffffff8c0aa880 RDI: ffffffff8c5e90a0 RBP: ffffc90000a18d30 R08: ffffffff9428288f R09: 1ffffffff2850511 R10: dffffc0000000000 R11: fffffbfff2850512 R12: ffff8880b872c880 R13: 1ffff92000143194 R14: ffffc90000a18cc0 R15: dffffc0000000000 FS: 00007f1799abe6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c38dc6f CR3: 0000000027af2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1743 [inline] __hrtimer_run_queues+0x670/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:87 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x86/0x290 mm/kasan/generic.c:189 Code: 00 fc ff df 4f 8d 3c 31 4c 89 fd 4c 29 dd 48 83 fd 10 7f 29 48 85 ed 0f 84 3e 01 00 00 4c 89 cd 48 f7 d5 48 01 dd 41 80 3b 00 <0f> 85 c9 01 00 00 49 ff c3 48 ff c5 75 ee e9 1e 01 00 00 45 89 dc RSP: 0018:ffffc90003077ae8 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 1ffff9200060ef8a RCX: ffffffff84f9b296 RDX: 0000000000000001 RSI: 000000000000007f RDI: ffffc90003077c50 RBP: fffffffffffffff8 R08: ffffc90003077cce R09: 1ffff9200060ef99 R10: dffffc0000000000 R11: fffff5200060ef92 R12: 0000000000000000 R13: dffffc0000000000 R14: dffffc0000000001 R15: fffff5200060ef9a strncpy_from_user+0x76/0x270 lib/strncpy_from_user.c:123 bpf_prog_load+0xd65/0x20f0 kernel/bpf/syscall.c:2888 __sys_bpf+0x4ee/0x810 kernel/bpf/syscall.c:5790 __do_sys_bpf kernel/bpf/syscall.c:5897 [inline] __se_sys_bpf kernel/bpf/syscall.c:5895 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5895 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: 0033:0x7f1798d7ff19 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:00007f1799abe058 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f1798f46080 RCX: 00007f1798d7ff19 RDX: 0000000000000090 RSI: 0000000020000300 RDI: 0000000000000005 RBP: 00007f1798df3986 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1798f46080 R15: 00007ffe099f80c8 rcu: rcu_preempt kthread starved for 10505 jiffies! g41089 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:25976 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 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: 0 UID: 0 PID: 54 Comm: kworker/u8:3 Not tainted 6.13.0-rc1-syzkaller-00002-gcdd30ebb1b9f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f3/0x2c60 kernel/smp.c:884 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 66 e9 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 11 e5 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 f5 e4 RSP: 0018:ffffc90000be76e0 EFLAGS: 00000293 RAX: ffffffff81938cdb RBX: 1ffff110170e88b9 RCX: ffff8880212eda00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000be78e0 R08: ffffffff81938caa R09: 1ffffffff2850510 R10: dffffc0000000000 R11: fffffbfff2850511 R12: dffffc0000000000 R13: ffff8880b87445c8 R14: ffff8880b863f940 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0ec1c51f4e CR3: 000000000e736000 CR4: 00000000003526f0 DR0: fffffffffffffffd DR1: 0000000000000000 DR2: fffffffffffffffe DR3: 000000007fffffff DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:849 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 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