Hello, syzbot found the following issue on: HEAD commit: 4a57a8400075 vf/remap: return the amount of bytes actually.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=119ac0fc080000 kernel config: https://syzkaller.appspot.com/x/.config?x=cd73026ceaed1402 dashboard link: https://syzkaller.appspot.com/bug?extid=7c9e87a5d6b088cd78a3 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7c9e87a5d6b088cd78a3@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ WARNING: CPU: 3 PID: 33 at drivers/block/floppy.c:999 schedule_bh drivers/block/floppy.c:999 [inline] WARNING: CPU: 3 PID: 33 at drivers/block/floppy.c:999 floppy_interrupt+0x32b/0x3a0 drivers/block/floppy.c:1765 Modules linked in: CPU: 3 PID: 33 Comm: ksoftirqd/3 Not tainted 5.19.0-rc6-syzkaller-00115-g4a57a8400075 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 RIP: 0010:schedule_bh drivers/block/floppy.c:999 [inline] RIP: 0010:floppy_interrupt+0x32b/0x3a0 drivers/block/floppy.c:1765 Code: fe ff ff e8 87 25 e0 fc 0f b6 1d 80 24 89 0c 31 ff 89 de e8 77 21 e0 fc 84 db 0f 85 30 b6 ad 04 e9 18 fe ff ff e8 65 25 e0 fc <0f> 0b e9 1a ff ff ff e8 29 e1 2c fd e9 ed fd ff ff e8 1f e1 2c fd RSP: 0018:ffffc900005d8e58 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000100 RDX: ffff888012229d80 RSI: ffffffff849a457b RDI: 0000000000000007 RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000002 R13: ffffffff8499f800 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88802cb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f6f5c034 CR3: 000000000ba8e000 CR4: 0000000000150ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> floppy_hardint+0x1ad/0x200 arch/x86/include/asm/floppy.h:66 __handle_irq_event_percpu+0x22b/0x880 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xa7/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:817 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline] handle_irq arch/x86/kernel/irq.c:231 [inline] __common_interrupt+0x9d/0x210 arch/x86/kernel/irq.c:250 common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240 </IRQ> <TASK> asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:640 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 ca de e3 f7 48 89 ef e8 d2 5f e4 f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 43 67 d7 f7 65 8b 05 fc fb 87 76 85 c0 74 0a 5b 5d c3 e8 90 46 RSP: 0018:ffffc900005afbe0 EFLAGS: 00000206 RAX: 0000000000000006 RBX: 0000000000000200 RCX: 1ffffffff1b77019 RDX: 0000000000000000 RSI: 0000000000000101 RDI: 0000000000000001 RBP: ffffffff91193240 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff2232648 R11: 0000000000000001 R12: 0000000000000002 R13: 0000000000000002 R14: dead000000000100 R15: dffffc0000000000 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline] debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1020 slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0xeb/0x1c0 mm/slub.c:1780 slab_free mm/slub.c:3536 [inline] kmem_cache_free+0xdd/0x5a0 mm/slub.c:3553 i_callback+0x3f/0x70 fs/inode.c:249 rcu_do_batch kernel/rcu/tree.c:2578 [inline] rcu_core+0x7b1/0x1880 kernel/rcu/tree.c:2838 __do_softirq+0x29b/0x9c2 kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 </TASK> ---------------- Code disassembly (best guess): 0: 74 24 je 0x26 2: 10 e8 adc %ch,%al 4: ca de e3 lret $0xe3de 7: f7 48 89 ef e8 d2 5f testl $0x5fd2e8ef,-0x77(%rax) e: e4 f7 in $0xf7,%al 10: 81 e3 00 02 00 00 and $0x200,%ebx 16: 75 25 jne 0x3d 18: 9c pushfq 19: 58 pop %rax 1a: f6 c4 02 test $0x2,%ah 1d: 75 2d jne 0x4c 1f: 48 85 db test %rbx,%rbx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 43 67 d7 f7 callq 0xf7d76772 <-- trapping instruction 2f: 65 8b 05 fc fb 87 76 mov %gs:0x7687fbfc(%rip),%eax # 0x7687fc32 36: 85 c0 test %eax,%eax 38: 74 0a je 0x44 3a: 5b pop %rbx 3b: 5d pop %rbp 3c: c3 retq 3d: e8 .byte 0xe8 3e: 90 nop 3f: 46 rex.RX --- This report is generated by a bot. 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