Hello, syzbot found the following issue on: HEAD commit: 0a9b9d17f3a7 Merge tag 'pm-6.12-rc8' of git://git.kernel.o.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17bf6ce8580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d2aeec8c0b2e420c dashboard link: https://syzkaller.appspot.com/bug?extid=f303608297c771a7de35 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/8a8c49f7786f/disk-0a9b9d17.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0f9c24f45e74/vmlinux-0a9b9d17.xz kernel image: https://storage.googleapis.com/syzbot-assets/b1f469ce7e16/bzImage-0a9b9d17.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+f303608297c771a7de35@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: trying to register non-static key. The code is fine but needs lockdep annotation, or maybe you didn't initialize this object before use? turning off the locking correctness validator. CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0-rc7-syzkaller-00070-g0a9b9d17f3a7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 assign_lock_key+0x241/0x280 kernel/locking/lockdep.c:981 register_lock_class+0x1cf/0x980 kernel/locking/lockdep.c:1295 __lock_acquire+0xf0/0x2050 kernel/locking/lockdep.c:5077 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 start_wakeup_event drivers/virtio/virtio_balloon.c:150 [inline] stats_request+0xb3/0x230 drivers/virtio/virtio_balloon.c:440 vring_interrupt+0x21d/0x380 drivers/virtio/virtio_ring.c:2595 vp_vring_interrupt drivers/virtio/virtio_pci_common.c:92 [inline] vp_interrupt+0x192/0x200 drivers/virtio/virtio_pci_common.c:123 __handle_irq_event_percpu+0x29a/0xa80 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0x89/0x1f0 kernel/irq/handle.c:210 handle_fasteoi_irq+0x48a/0xae0 kernel/irq/chip.c:720 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline] handle_irq arch/x86/kernel/irq.c:247 [inline] call_irq_handler arch/x86/kernel/irq.c:259 [inline] __common_interrupt+0x136/0x230 arch/x86/kernel/irq.c:285 common_interrupt+0xb4/0xd0 arch/x86/kernel/irq.c:278 </IRQ> <TASK> asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5829 Code: 2b 00 74 08 4c 89 f7 e8 ea 6c 8e 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0000:ffffc90000067360 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200000ce78 RCX: c155c4d26c75e500 RDX: dffffc0000000000 RSI: ffffffff8c0adc40 RDI: ffffffff8c610b20 RBP: ffffc900000674a8 R08: ffffffff942d0857 R09: 1ffffffff285a10a R10: dffffc0000000000 R11: fffffbfff285a10b R12: 1ffff9200000ce74 R13: dffffc0000000000 R14: ffffc900000673c0 R15: 0000000000000246 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 __blocking_notifier_chain_register kernel/notifier.c:271 [inline] blocking_notifier_chain_register+0x50/0xc0 kernel/notifier.c:290 virtballoon_probe+0x551/0xf60 drivers/virtio/virtio_balloon.c:1015 virtio_dev_probe+0x931/0xc80 drivers/virtio/virtio.c:341 really_probe+0x2b8/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __driver_attach+0x45f/0x710 drivers/base/dd.c:1216 bus_for_each_dev+0x239/0x2b0 drivers/base/bus.c:370 bus_add_driver+0x346/0x670 drivers/base/bus.c:675 driver_register+0x23a/0x320 drivers/base/driver.c:246 do_one_initcall+0x248/0x880 init/main.c:1269 do_initcall_level+0x157/0x210 init/main.c:1331 do_initcalls+0x3f/0x80 init/main.c:1347 kernel_init_freeable+0x435/0x5d0 init/main.c:1580 kernel_init+0x1d/0x2b0 init/main.c:1469 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> ---------------- Code disassembly (best guess): 0: 2b 00 sub (%rax),%eax 2: 74 08 je 0xc 4: 4c 89 f7 mov %r14,%rdi 7: e8 ea 6c 8e 00 call 0x8e6cf6 c: f6 44 24 61 02 testb $0x2,0x61(%rsp) 11: 0f 85 85 01 00 00 jne 0x19c 17: 41 f7 c7 00 02 00 00 test $0x200,%r15d 1e: 74 01 je 0x21 20: fb sti 21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp) 28: e0 45 * 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction 31: 00 00 33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1) 3a: 00 00 3c: 43 rex.XB 3d: c7 .byte 0xc7 3e: 44 rex.R 3f: 25 .byte 0x25 --- This report is generated by a bot. 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