------------[ cut here ]------------ WARNING: CPU: 1 PID: 1096 at kernel/rcu/tree_stall.h:989 rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:989 Modules linked in: CPU: 1 UID: 0 PID: 1096 Comm: kworker/u8:6 Not tainted 6.15.0-syzkaller-g90b83efa6701 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:989 Code: ff ff 48 c7 c7 60 24 ab 99 be 04 00 00 00 e8 93 b5 7b 00 4c 89 f7 b8 01 00 00 00 87 05 b5 be 03 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 80 20 14 8e 74 47 48 c7 c0 f0 e2 a0 8f 48 c1 e8 RSP: 0018:ffffc90000a08bb8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000a02 RCX: ffffffff81a7659d RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e142080 RBP: ffffc90000a08e30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff335648c R12: 0000000000002904 R13: 1ffff110170e793a R14: ffffffff8e142080 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125d66000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc3386e5000 CR3: 000000000df36000 CR4: 00000000003526f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_core+0x5f7/0x1710 kernel/rcu/tree.c:2827 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0xe69/0x11c0 kernel/smp.c:885 Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 b0 77 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 5b 73 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 40 73 0b RSP: 0018:ffffc90003cbf6a0 EFLAGS: 00000293 RAX: ffffffff81b487b0 RBX: ffff8880b873cc00 RCX: ffff888026fc5a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003cbf800 R08: ffffffff8fa0b1b7 R09: 1ffffffff1f41636 R10: dffffc0000000000 R11: fffffbfff1f41637 R12: 1ffff110170c8681 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8643408 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2660 [inline] smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2870 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 45 8b 2f mov (%r15),%r13d 3: 44 89 ee mov %r13d,%esi 6: 83 e6 01 and $0x1,%esi 9: 31 ff xor %edi,%edi b: e8 b0 77 0b 00 call 0xb77c0 10: 41 83 e5 01 and $0x1,%r13d 14: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13 1b: fc ff df 1e: 75 07 jne 0x27 20: e8 5b 73 0b 00 call 0xb7380 25: eb 37 jmp 0x5e 27: f3 90 pause * 29: 43 0f b6 04 2c movzbl (%r12,%r13,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 75 10 jne 0x42 32: 41 f7 07 01 00 00 00 testl $0x1,(%r15) 39: 74 1e je 0x59 3b: e8 .byte 0xe8 3c: 40 73 0b rex jae 0x4a