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WARNING: CPU: 0 PID: 20887 at kernel/rcu/tree_stall.h:1050 rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1050
Modules linked in:
CPU: 0 UID: 0 PID: 20887 Comm: syz.4.3851 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1050
Code: ff ff 48 c7 c7 60 d4 58 99 be 04 00 00 00 e8 93 73 7e 00 4c 89 f7 b8 01 00 00 00 87 05 15 23 b3 17 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 80 04 d4 8d 74 47 48 c7 c0 30 1d 5c 8f 48 c1 e8
RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000a02 RCX: ffffffff81a5b13d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8dd40480
RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff32b1a8c R12: 0000000000002904
R13: 1ffff110171075fa R14: ffffffff8dd40480 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff88812638a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c38939d CR3: 000000000db36000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
rcu_core+0x5fa/0x1770 kernel/rcu/tree.c:2856
handle_softirqs+0x283/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 96 73 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 41 6f 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 25 6f
RSP: 0018:ffffc9000d0ef5e0 EFLAGS: 00000293
RAX: ffffffff81b3103b RBX: 1ffff11017127ff5 RCX: ffff888030ad0000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000d0ef760 R08: ffffffff8f5bed37 R09: 1ffffffff1eb7da6
R10: dffffc0000000000 R11: fffffbfff1eb7da7 R12: ffff8880b893ffa8
R13: dffffc0000000000 R14: ffff8880b883b200 R15: 0000000000000001
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
__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+0x6b1/0x12d0 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+0x174/0xb40 mm/mmap.c:1266
__mmput+0x118/0x430 kernel/fork.c:1133
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:954
__do_sys_exit kernel/exit.c:1074 [inline]
__se_sys_exit kernel/exit.c:1072 [inline]
__x64_sys_exit+0x40/0x40 kernel/exit.c:1072
x64_sys_call+0x21da/0x2200 arch/x86/include/generated/asm/syscalls_64.h:61
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8137f8eec9
Code: Unable to access opcode bytes at 0x7f8137f8ee9f.
RSP: 002b:00007f8138de6fe8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c
RAX: ffffffffffffffda RBX: 00007f81381e5fa0 RCX: 00007f8137f8eec9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f8138011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f81381e6038 R14: 00007f81381e5fa0 R15: 00007ffd43596df8
----------------
Code disassembly (best guess):
0: 45 8b 2c 24 mov (%r12),%r13d
4: 44 89 ee mov %r13d,%esi
7: 83 e6 01 and $0x1,%esi
a: 31 ff xor %edi,%edi
c: e8 96 73 0b 00 call 0xb73a7
11: 41 83 e5 01 and $0x1,%r13d
15: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13
1c: fc ff df
1f: 75 07 jne 0x28
21: e8 41 6f 0b 00 call 0xb6f67
26: eb 38 jmp 0x60
28: f3 90 pause
* 2a: 42 0f b6 04 2b movzbl (%rbx,%r13,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 75 11 jne 0x44
33: 41 f7 04 24 01 00 00 testl $0x1,(%r12)
3a: 00
3b: 74 1e je 0x5b
3d: e8 .byte 0xe8
3e: 25 .byte 0x25
3f: 6f outsl %ds:(%rsi),(%dx)