BUG: spinlock already unlocked on CPU#0, syz.2.25/6044 lock: 0xffff888032ea0ea0, .magic: dead4ead, .owner: /-1, .owner_cpu: -1 CPU: 0 UID: 0 PID: 6044 Comm: syz.2.25 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 spin_bug kernel/locking/spinlock_debug.c:78 [inline] debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline] do_raw_spin_unlock+0x143/0x210 kernel/locking/spinlock_debug.c:141 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:177 [inline] _raw_spin_unlock_irqrestore+0x23/0x80 kernel/locking/spinlock.c:198 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] lec_arp_destroy net/atm/lec.c:1543 [inline] lec_atm_close+0x976/0x9e0 net/atm/lec.c:497 vcc_destroy_socket net/atm/common.c:181 [inline] vcc_release+0x10f/0x580 net/atm/common.c:205 svc_release+0x6c/0xd0 net/atm/svc.c:95 __sock_release net/socket.c:722 [inline] sock_close+0xc3/0x240 net/socket.c:1514 __fput+0x44f/0xa60 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 get_signal+0x11eb/0x1330 kernel/signal.c:2811 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1af9f9c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1afae30028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007f1afa215fa0 RCX: 00007f1af9f9c819 RDX: 0000000000000000 RSI: 00000000000061d0 RDI: 0000000000000005 RBP: 00007f1afa032c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1afa216038 R14: 00007f1afa215fa0 R15: 00007ffdc6f7add8 ------------[ cut here ]------------ pvqspinlock: lock 0xffff888032ea0ea0 has corrupted value 0x0! WARNING: kernel/locking/qspinlock_paravirt.h:506 at __pv_queued_spin_unlock_slowpath+0x1a5/0x270 kernel/locking/qspinlock_paravirt.h:504, CPU#0: syz.2.25/6044 Modules linked in: CPU: 0 UID: 0 PID: 6044 Comm: syz.2.25 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:__pv_queued_spin_unlock_slowpath+0x1ce/0x270 kernel/locking/qspinlock_paravirt.h:504 Code: 04 48 89 df be 04 00 00 00 e8 4e 58 7b f6 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 87 00 00 00 8b 13 4c 89 f7 48 89 de <67> 48 0f b9 3a eb 98 48 c7 c7 30 c8 82 8e 4c 89 f6 4c 89 fa e8 f9 RSP: 0018:ffffc90005087920 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff888032ea0ea0 RCX: ffffffff8bb5d542 RDX: 0000000000000000 RSI: ffff888032ea0ea0 RDI: ffffffff90357220 RBP: 1ffff110065d41d5 R08: ffff888032ea0ea3 R09: 1ffff110065d41d4 R10: dffffc0000000000 R11: ffffed10065d41d5 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffffff90357220 R15: ffff888032ea0ea8 FS: 00007f1afae306c0(0000) GS:ffff888125245000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1994be92f8 CR3: 000000007abce000 CR4: 00000000003526f0 Call Trace: __raw_callee_save___pv_queued_spin_unlock_slowpath+0x15/0x30 .slowpath+0x9/0x18 pv_queued_spin_unlock arch/x86/include/asm/paravirt-spinlock.h:40 [inline] queued_spin_unlock arch/x86/include/asm/paravirt-spinlock.h:72 [inline] do_raw_spin_unlock+0xf5/0x210 kernel/locking/spinlock_debug.c:142 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:177 [inline] _raw_spin_unlock_irqrestore+0x23/0x80 kernel/locking/spinlock.c:198 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] lec_arp_destroy net/atm/lec.c:1543 [inline] lec_atm_close+0x976/0x9e0 net/atm/lec.c:497 vcc_destroy_socket net/atm/common.c:181 [inline] vcc_release+0x10f/0x580 net/atm/common.c:205 svc_release+0x6c/0xd0 net/atm/svc.c:95 __sock_release net/socket.c:722 [inline] sock_close+0xc3/0x240 net/socket.c:1514 __fput+0x44f/0xa60 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 get_signal+0x11eb/0x1330 kernel/signal.c:2811 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1af9f9c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1afae30028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007f1afa215fa0 RCX: 00007f1af9f9c819 RDX: 0000000000000000 RSI: 00000000000061d0 RDI: 0000000000000005 RBP: 00007f1afa032c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1afa216038 R14: 00007f1afa215fa0 R15: 00007ffdc6f7add8 ---------------- Code disassembly (best guess): 0: 04 48 add $0x48,%al 2: 89 df mov %ebx,%edi 4: be 04 00 00 00 mov $0x4,%esi 9: e8 4e 58 7b f6 call 0xf67b585c e: 48 89 d8 mov %rbx,%rax 11: 48 c1 e8 03 shr $0x3,%rax 15: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 1a: 84 c0 test %al,%al 1c: 0f 85 87 00 00 00 jne 0xa9 22: 8b 13 mov (%rbx),%edx 24: 4c 89 f7 mov %r14,%rdi 27: 48 89 de mov %rbx,%rsi * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: eb 98 jmp 0xffffffc9 31: 48 c7 c7 30 c8 82 8e mov $0xffffffff8e82c830,%rdi 38: 4c 89 f6 mov %r14,%rsi 3b: 4c 89 fa mov %r15,%rdx 3e: e8 .byte 0xe8 3f: f9 stc