------------[ cut here ]------------ WARNING: CPU: 0 PID: 2407 at kernel/rcu/tree_stall.h:990 rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:990 Modules linked in: CPU: 0 PID: 2407 Comm: kworker/u4:8 Not tainted 6.7.0-rc3-syzkaller-00811-gd16f1096b320 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:rcu_check_gp_start_stall.part.0+0x1c4/0x4b0 kernel/rcu/tree_stall.h:990 Code: 88 5d 01 00 00 be 04 00 00 00 48 c7 c7 c0 5a 80 92 e8 80 5b 6d 00 b8 01 00 00 00 87 05 25 3c 0f 11 85 c0 0f 85 39 01 00 00 90 <0f> 0b 90 48 81 fd c0 6e fb 8c 48 c7 c3 b8 29 19 8f 74 5a 48 b8 00 RSP: 0018:ffffc90000007df0 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000002904 RCX: ffffffff81711e90 RDX: fffffbfff2500b58 RSI: 0000000000000004 RDI: ffffffff92805ac0 RBP: ffffffff8cfb6ec0 R08: 0000000000000001 R09: fffffbfff2500b58 R10: 0000000000000003 R11: 0000000000000005 R12: 1ffffffff1981e40 R13: 0000000000000246 R14: ffffffff8cfb6ec0 R15: ffff8880b983d612 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc455ac35c0 CR3: 000000000cd77000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_check_gp_start_stall kernel/rcu/tree_stall.h:953 [inline] rcu_core+0x4e1/0x1680 kernel/rcu/tree.c:2426 __do_softirq+0x21a/0x8de kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu kernel/softirq.c:632 [inline] irq_exit_rcu+0xb7/0x120 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x4e4/0x1550 kernel/smp.c:855 Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 8e c0 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 24 0e 00 00 8b 43 08 31 RSP: 0018:ffffc9000a857930 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9941a60 RCX: ffffffff817bd1e8 RDX: ffff888025c3bb80 RSI: ffffffff817bd1c2 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed101732834d R13: 0000000000000001 R14: ffff8880b9941a68 R15: ffff8880b983d8c0 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2006 [inline] text_poke_bp_batch+0x22b/0x750 arch/x86/kernel/alternative.c:2216 text_poke_flush arch/x86/kernel/alternative.c:2407 [inline] text_poke_flush arch/x86/kernel/alternative.c:2404 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2414 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:830 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 ---------------- Code disassembly (best guess): 0: 0b 00 or (%rax),%eax 2: 85 ed test %ebp,%ebp 4: 74 4d je 0x53 6: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax d: fc ff df 10: 4d 89 f4 mov %r14,%r12 13: 4c 89 f5 mov %r14,%rbp 16: 49 c1 ec 03 shr $0x3,%r12 1a: 83 e5 07 and $0x7,%ebp 1d: 49 01 c4 add %rax,%r12 20: 83 c5 03 add $0x3,%ebp 23: e8 8e c0 0b 00 call 0xbc0b6 28: f3 90 pause * 2a: 41 0f b6 04 24 movzbl (%r12),%eax <-- trapping instruction 2f: 40 38 c5 cmp %al,%bpl 32: 7c 08 jl 0x3c 34: 84 c0 test %al,%al 36: 0f 85 24 0e 00 00 jne 0xe60 3c: 8b 43 08 mov 0x8(%rbx),%eax 3f: 31 .byte 0x31