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WARNING: CPU: 1 PID: 8 at drivers/block/floppy.c:988 schedule_bh+0x5f/0x70 drivers/block/floppy.c:988
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 8 Comm: kworker/u16:0 Not tainted 5.6.0-rc5-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Workqueue: floppy floppy_work_workfn
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x35 kernel/panic.c:582
 report_bug+0x27b/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 fixup_bug arch/x86/kernel/traps.c:169 [inline]
 do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:schedule_bh+0x5f/0x70 drivers/block/floppy.c:988
Code: d7 23 1b fd 48 89 2d 20 3a 96 08 5b 48 c7 c2 00 bd e5 89 48 8b 35 f1 3e 96 08 bf 40 00 00 00 5d e9 c6 5a f4 fc e8 b1 23 1b fd <0f> 0b eb d1 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 e8 9b 23 1b fd
RSP: 0018:ffffc900004e8dd8 EFLAGS: 00010006
RAX: ffff88802c598200 RBX: 0000000000000001 RCX: ffffffff8456f1cf
RDX: 0000000000010000 RSI: ffffffff8456f1ff RDI: 0000000000000007
RBP: ffffffff8456edf0 R08: ffff88802c598200 R09: fffffbfff13cb7a1
R10: fffffbfff13cb7a0 R11: ffffffff89e5bd07 R12: 0000000000000001
R13: 00000000000003f0 R14: 0000000000000000 R15: ffff88802cd138a8
 floppy_interrupt+0x202/0x2e0 drivers/block/floppy.c:1735
 floppy_hardint+0x256/0x320 arch/x86/include/asm/floppy.h:66
 __handle_irq_event_percpu+0x15d/0x950 kernel/irq/handle.c:149
 handle_irq_event_percpu+0x76/0x160 kernel/irq/handle.c:189
 handle_irq_event+0xa2/0x12d kernel/irq/handle.c:206
 handle_edge_irq+0x24b/0x8c0 kernel/irq/chip.c:830
 generic_handle_irq_desc include/linux/irqdesc.h:156 [inline]
 do_IRQ+0xd9/0x280 arch/x86/kernel/irq.c:250
 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:607
 </IRQ>
RIP: 0010:slow_down_io arch/x86/include/asm/paravirt.h:42 [inline]
RIP: 0010:outb_p arch/x86/include/asm/io.h:334 [inline]
RIP: 0010:output_byte+0xfa/0x320 drivers/block/floppy.c:1132
Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 21 02 00 00 48 8d 44 ad 00 48 8b 14 c5 70 31 ed 8c 44 89 e0 83 c2 05 ee <48> c7 c5 b8 b3 73 89 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1
RSP: 0018:ffffc900003bfc50 EFLAGS: 00000206 ORIG_RAX: ffffffffffffffdd
RAX: 00000000fffffff6 RBX: 0000000000000090 RCX: ffffffff84578a02
RDX: 00000000000003f5 RSI: ffffffff84578a7b RDI: ffffffff8ced3170
RBP: 0000000000000000 R08: ffff88802c598200 R09: fffffbfff180e580
R10: fffffbfff180e57f R11: ffffffff8c072bff R12: 00000000fffffff6
R13: 0000000000000000 R14: 0000000000000005 R15: 0000000000000008
 setup_rw_floppy+0x15a/0x7c0 drivers/block/floppy.c:1499
 seek_floppy drivers/block/floppy.c:1609 [inline]
 floppy_ready drivers/block/floppy.c:1921 [inline]
 floppy_ready+0x3a2/0x14a0 drivers/block/floppy.c:1893
 redo_format+0x4a1/0x690 drivers/block/floppy.c:2174
 process_one_work+0x94b/0x1690 kernel/workqueue.c:2266
 worker_thread+0x96/0xe20 kernel/workqueue.c:2412
 kthread+0x357/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..