Re: [Qemu-devel] commit 094b287 "Add USB option in machine options" broke i386 -usb

[Li Zhang <zhlcindy@linux.vnet.ibm.com>]

On 2012年11月23日 00:18, Peter Maydell wrote:
> On 29 October 2012 10:25, Alexander Graf <agraf@suse.de> wrote:
>> From: zhlcindy@gmail.com <zhlcindy@gmail.com>
>>
>> When -usb option is used, global varible usb_enabled is set.
>> And all the plaform will create one USB controller according
>> to this variable. In fact, global varibles make code hard
>> to read.
>>
>> So this patch is to remove global variable usb_enabled and
>> add USB option in machine options. All the plaforms will get
>> USB option value from machine options.
>>
>> USB option of machine options will be set either by:
>>    * -usb
>>    * -machine type=pseries,usb=on
>>
>> Both these ways can work now. They both set USB option in
>> machine options. In the future, the first way will be removed.
> This commit breaks "qemu-system-i386 -usb", which used to
> create a USB bus and now does not. Example to reproduce:
>
> $ dd if=/dev/zero bs=4096 count=1024 of=usb.img
> $ ./i386-softmmu/qemu-system-i386 -clock unix -monitor stdio -usb
> -drive if=none,file=usb.img,id=myusb  -device
> usb-storage,id=myusb,drive=myusb,removable=on
Hi Peter,

I am sorry to cause this problem.

I couldn't see  the machine's option in your command line.
such as, -machine type=pc

As it describes, you need to pass this option to enable USB.
Because USB option is set by machine's option.

Thanks. :-)
>
> should boot up, but now fails with:
> qemu-system-i386: -device
> usb-storage,id=myusb,drive=myusb,removable=on: No 'usb-bus' bus found
> for device 'usb-storage'
>
> This worked in 1.2 so it is a regression. In particular it
> presumably means that trying to migrate a VM from 1.2 qemu
> that used USB will fail.
>
> -- PMM
>


-- 

Li Zhang
IBM China Linux Technology Centre