------------[ cut here ]------------ WARNING: CPU: 1 PID: 4921 at drivers/block/floppy.c:999 schedule_bh drivers/block/floppy.c:999 [inline] WARNING: CPU: 1 PID: 4921 at drivers/block/floppy.c:999 floppy_interrupt+0x3cc/0x440 drivers/block/floppy.c:1765 Modules linked in: CPU: 1 PID: 4921 Comm: kworker/u16:2 Not tainted 6.4.0-syzkaller-01224-g1ef6663a587b #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Workqueue: floppy floppy_work_workfn RIP: 0010:schedule_bh drivers/block/floppy.c:999 [inline] RIP: 0010:floppy_interrupt+0x3cc/0x440 drivers/block/floppy.c:1765 Code: 4d d0 8a 89 c6 89 05 73 c4 ea 0c e8 8e 27 ff ff 8b 1d 68 c4 ea 0c e9 9c fd ff ff e8 ce 56 b1 fc e9 66 fd ff ff e8 24 67 5f fc <0f> 0b e9 c9 fe ff ff 48 c7 c7 00 f2 40 8c e8 71 56 b1 fc e9 5a fc RSP: 0018:ffffc90000aa8e58 EFLAGS: 00010046 RAX: 0000000080010000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: ffff888031a98800 RSI: ffffffff852425ac RDI: 0000000000000001 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffffc90000aa8ff8 R12: ffffffff85239f60 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000006 FS: 0000000000000000(0000) GS:ffff88806b700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055cd072ef000 CR3: 000000000c571000 CR4: 0000000000350ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: floppy_hardint+0x1b1/0x200 arch/x86/include/asm/floppy.h:66 __handle_irq_event_percpu+0x22b/0x730 kernel/irq/handle.c:158 handle_irq_event_percpu kernel/irq/handle.c:193 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210 handle_edge_irq+0x263/0xd00 kernel/irq/chip.c:834 generic_handle_irq_desc include/linux/irqdesc.h:161 [inline] handle_irq arch/x86/kernel/irq.c:238 [inline] __common_interrupt+0xa1/0x220 arch/x86/kernel/irq.c:257 common_interrupt+0xa8/0xd0 arch/x86/kernel/irq.c:247 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:636 RIP: 0010:outb_p arch/x86/include/asm/io.h:296 [inline] RIP: 0010:fdc_outb drivers/block/floppy.c:602 [inline] RIP: 0010:reset_fdc+0x185/0x400 drivers/block/floppy.c:1817 Code: ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 11 00 0f 85 8a 01 00 00 48 8d 14 9b 48 8b 14 d5 f0 c0 0e 92 83 c2 04 ee 56 ec ff ff 48 83 c4 08 5b 5d e9 9b 1f 60 fc e8 96 1f 60 fc 48 RSP: 0018:ffffc9000308fc70 EFLAGS: 00000202 RAX: 00000000ffffff81 RBX: 0000000000000000 RCX: 1ffffffff241d81e RDX: 00000000000003f4 RSI: ffffffff85236c9c RDI: ffffffff920ec0f0 RBP: 0000000000000062 R08: 0000000000000001 R09: 0000000000000044 R10: 0000000000000062 R11: 0000000032393454 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000020 R15: 0000ffff88800010 floppy_ready+0x67c/0x1b60 drivers/block/floppy.c:1929 redo_format+0x545/0x6f0 drivers/block/floppy.c:2214 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2408 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2555 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 ---------------- Code disassembly (best guess): 0: ba 00 00 00 00 mov $0x0,%edx 5: 00 fc add %bh,%ah 7: ff (bad) 8: df 48 89 fisttps -0x77(%rax) b: f9 stc c: 48 c1 e9 03 shr $0x3,%rcx 10: 80 3c 11 00 cmpb $0x0,(%rcx,%rdx,1) 14: 0f 85 8a 01 00 00 jne 0x1a4 1a: 48 8d 14 9b lea (%rbx,%rbx,4),%rdx 1e: 48 8b 14 d5 f0 c0 0e mov -0x6df13f10(,%rdx,8),%rdx 25: 92 26: 83 c2 04 add $0x4,%edx 29: ee out %al,(%dx) * 2a: e8 56 ec ff ff callq 0xffffec85 <-- trapping instruction 2f: 48 83 c4 08 add $0x8,%rsp 33: 5b pop %rbx 34: 5d pop %rbp 35: e9 9b 1f 60 fc jmpq 0xfc601fd5 3a: e8 96 1f 60 fc callq 0xfc601fd5 3f: 48 rex.W