------------[ cut here ]------------ WARNING: CPU: 0 PID: 10733 at kernel/rcu/tree_stall.h:1015 rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1015 Modules linked in: CPU: 0 UID: 0 PID: 10733 Comm: syz.1.1227 Not tainted 6.16.0-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1015 Code: ff ff 48 c7 c7 00 04 ac 99 be 04 00 00 00 e8 63 51 78 00 4c 89 f7 b8 01 00 00 00 87 05 b5 45 04 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 80 44 14 8e 74 47 48 c7 c0 30 e5 a0 8f 48 c1 e8 RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000a02 RCX: ffffffff81a7be3d RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e144480 RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff3358080 R12: 0000000000002904 R13: 1ffff110170c75c2 R14: ffffffff8e144480 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125c57000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c34c1ba CR3: 000000000df38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 000000000000000a DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: rcu_core+0x5f7/0x1710 kernel/rcu/tree.c:2827 handle_softirqs+0x283/0x870 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+0xf69/0x12d0 kernel/smp.c:885 Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 80 6e 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 2b 6a 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 10 6a 0b RSP: 0018:ffffc90003fbf360 EFLAGS: 00000293 RAX: ffffffff81b4bbb0 RBX: ffff8880b863b040 RCX: ffff888020b7da00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90003fbf4c0 R08: ffffffff8fa0b3f7 R09: 1ffffffff1f4167e R10: dffffc0000000000 R11: fffffbfff1f4167f R12: 1ffff110170e7f2d R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b873f968 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline] tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497 free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411 arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline] exit_mmap+0x17c/0xb50 mm/mmap.c:1270 __mmput+0x118/0x410 kernel/fork.c:1121 exit_mm+0x1da/0x2c0 kernel/exit.c:581 do_exit+0x648/0x22e0 kernel/exit.c:952 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f32f5b8ebe9 Code: Unable to access opcode bytes at 0x7f32f5b8ebbf. RSP: 002b:00007f32f696e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f32f5db5fa8 RCX: 00007f32f5b8ebe9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f32f5db5fa8 RBP: 00007f32f5db5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f32f5db6038 R14: 00007fff32a18900 R15: 00007fff32a189e8 ---------------- 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 80 6e 0b 00 call 0xb6e90 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 2b 6a 0b 00 call 0xb6a50 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: 10 6a 0b adc %ch,0xb(%rdx)