Re: [Qemu-devel] device_del id missing after blockdev-add

[Stefan Hajnoczi]

On Mon, Feb 17, 2014 at 04:36:42PM +0100, William Dauchy wrote:
> I'm starting qemu with the following config in order to test drive
> hotremove and hotadd:
> 
> [drive "disk1"]
>   if = "none"
>   id = "disk1"
>   cache = "none"
>   aio = "native"
>   format = "raw"
>   file = "/dev/sda"
> 
> [device "disk1"]
>   driver = "scsi-hd"
>   drive = "disk1"
>   scsi-id = "1"
>   removable = "on"
>   vendor = "gandi.net"
>   dpofua = "off"
> 
> I'm now testing device removable without any problem:
> 
> (QEMU) device_del id=disk1
> {   u'return': {   }}
> (QEMU) 
> {u'timestamp': {u'seconds': 1392645815, u'microseconds': 484557}, u'data': 
> {u'device': u'disk1', u'path': u'/machine/peripheral/disk1'}, u'event': 
> u'DEVICE_DELETED'}
> 
> 
> then, I want to readd the disk, without anyproblem too (with the same
> id):
> 
> { "execute": "blockdev-add", "arguments": {'options' : {'driver': 'raw', 
> 'id':'disk1', 'file': {'driver': 'file', 'filename': '/dev/sda'}}} }
> { "device_add", "arguments": {'driver':'scsi-hd', 'drive':'disk1', 
> 'scsi-i':1, 'removable':on} }

Is 'scsi-i' a typo?  I guess you mean 'scsi-id'.

Also, it should probably be 'removable':true?

You forgot to give the device an ID.  Could that be the problem here?

> The issue is when I want to hot remove the disk again:
> 
> (QEMU) device_del id=disk1
> {   u'error': {   u'class': u'DeviceNotFound',
>                   u'desc': u"Device 'disk1' not found"}}
> 
> the output of query-block is the same everywhere:
> 
>                    {   u'device': u'disk1',
>                        u'inserted': {   u'backing_file_depth': 0,
>                                         u'bps': 0,
>                                         u'bps_rd': 0,
>                                         u'bps_wr': 0,
>                                         u'drv': u'raw',
>                                         u'encrypted': False,
>                                         u'encryption_key_missing': False,
>                                         u'file': u'/dev/sda',
>                                         u'image': {   u'actual-size': 0,
>                                                       u'dirty-flag': False,
>                                                       u'filename': 
> u'/dev/sda',
>                                                       u'format': u'raw',
>                                                       u'virtual-size': 
> 3221225472},
>                                         u'iops': 0,
>                                         u'iops_rd': 0,
>                                         u'iops_wr': 0,
>                                         u'ro': False},
>                        u'io-status': u'ok',
>                        u'locked': False,
>                        u'removable': True,
>                        u'tray_open': False,
>                        u'type': u'unknown'}]}

If the problem persists, please rerun the test with -drive
id=drive-disk1 and -device id=device-disk1.  That way it will be easier
to interpret the output.  It's confusing when both the drive and the
device are called "disk1".

Thanks,
Stefan