* [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible?
@ 2013-06-06 10:13 Alexey Kardashevskiy
2013-06-06 12:44 ` Frederic Konrad
0 siblings, 1 reply; 6+ messages in thread
From: Alexey Kardashevskiy @ 2013-06-06 10:13 UTC (permalink / raw)
To: qemu-devel@nongnu.org; +Cc: Michael S. Tsirkin
Hi!
For the pseries platform (server PPC64) we do not support PCI hotplug yet.
However we still want to hot plug disks.
As a workaround, we could add multiple SCSI host devices (virtio-scsi-pci,
spapr-vscsi) without any disk attached and later (using qemu console)
attach drives to them as we do with the "-drive" parameter in the command line.
So I enabled CONFIG_PCI_HOTPLUG_OLD=y and tried.
However, drive_add console command works only with PCI what eliminates
"spapr-vscsi" from the list. Oookay.
Then I tried running qemu with "-device virtio-scsi-pci,id=device0" and
later doing "drive_add 0 file=virtimg/test1" from the qemu console. This
time qemu responded with "Device is not a SCSI adapter" what is correct as
nowadays virtio-XXXX-pci devices are not what are they called as they
simply create underlying virtio-bus, attach a real virtio-XXXX-device there
(which is not PCI) and only then attach disk to non-PCI virtio device.
So as I see there is no way to attach a disk to an existing controller in
already running qemu.
This is how I add disks to qemu now:
-device virtio-scsi-pci,id=virtioscsi0 \
-drive file=virtimg/fc18guest,if=none,id=drive0,readonly=off,
format=raw,media=disk,werror=stop,rerror=stop \
-device scsi-disk,id=scsidisk0,bus=virtioscsi0.0,channel=0,
scsi-id=0,lun=0,drive=drive0,removable=off \
I want to only add "-device virtio-scsi-pci,id=virtioscsi0" to the command
line and do the rest from the qemu console.
Am I missing some useful command from qemu console or anything else? Thanks!
--
Alexey
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible?
2013-06-06 10:13 [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible? Alexey Kardashevskiy
@ 2013-06-06 12:44 ` Frederic Konrad
2013-06-06 13:59 ` Alexey Kardashevskiy
0 siblings, 1 reply; 6+ messages in thread
From: Frederic Konrad @ 2013-06-06 12:44 UTC (permalink / raw)
To: Alexey Kardashevskiy
Cc: fred.konrad, qemu-devel@nongnu.org, Michael S. Tsirkin
On 06/06/2013 12:13, Alexey Kardashevskiy wrote:
> Hi!
>
> For the pseries platform (server PPC64) we do not support PCI hotplug yet.
> However we still want to hot plug disks.
>
> As a workaround, we could add multiple SCSI host devices (virtio-scsi-pci,
> spapr-vscsi) without any disk attached and later (using qemu console)
> attach drives to them as we do with the "-drive" parameter in the command line.
>
> So I enabled CONFIG_PCI_HOTPLUG_OLD=y and tried.
>
> However, drive_add console command works only with PCI what eliminates
> "spapr-vscsi" from the list. Oookay.
>
> Then I tried running qemu with "-device virtio-scsi-pci,id=device0" and
> later doing "drive_add 0 file=virtimg/test1" from the qemu console. This
> time qemu responded with "Device is not a SCSI adapter" what is correct as
> nowadays virtio-XXXX-pci devices are not what are they called as they
> simply create underlying virtio-bus, attach a real virtio-XXXX-device there
> (which is not PCI) and only then attach disk to non-PCI virtio device.
Hi,
Seems it's a bug: il should be compatible with the old virtio-scsi-pci.
What's the meaning of the "0" in drive_add command?
Fred
>
> So as I see there is no way to attach a disk to an existing controller in
> already running qemu.
>
> This is how I add disks to qemu now:
> -device virtio-scsi-pci,id=virtioscsi0 \
> -drive file=virtimg/fc18guest,if=none,id=drive0,readonly=off,
> format=raw,media=disk,werror=stop,rerror=stop \
> -device scsi-disk,id=scsidisk0,bus=virtioscsi0.0,channel=0,
> scsi-id=0,lun=0,drive=drive0,removable=off \
>
> I want to only add "-device virtio-scsi-pci,id=virtioscsi0" to the command
> line and do the rest from the qemu console.
>
> Am I missing some useful command from qemu console or anything else? Thanks!
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible?
2013-06-06 12:44 ` Frederic Konrad
@ 2013-06-06 13:59 ` Alexey Kardashevskiy
2013-06-06 14:29 ` Frederic Konrad
0 siblings, 1 reply; 6+ messages in thread
From: Alexey Kardashevskiy @ 2013-06-06 13:59 UTC (permalink / raw)
To: Frederic Konrad; +Cc: qemu-devel@nongnu.org, Michael S. Tsirkin
On 06.06.2013 22:44, Frederic Konrad wrote:
> On 06/06/2013 12:13, Alexey Kardashevskiy wrote:
>> Hi!
>>
>> For the pseries platform (server PPC64) we do not support PCI hotplug
>> yet.
>> However we still want to hot plug disks.
>>
>> As a workaround, we could add multiple SCSI host devices
>> (virtio-scsi-pci,
>> spapr-vscsi) without any disk attached and later (using qemu console)
>> attach drives to them as we do with the "-drive" parameter in the
>> command line.
>>
>> So I enabled CONFIG_PCI_HOTPLUG_OLD=y and tried.
>>
>> However, drive_add console command works only with PCI what eliminates
>> "spapr-vscsi" from the list. Oookay.
>>
>> Then I tried running qemu with "-device virtio-scsi-pci,id=device0" and
>> later doing "drive_add 0 file=virtimg/test1" from the qemu console. This
>> time qemu responded with "Device is not a SCSI adapter" what is
>> correct as
>> nowadays virtio-XXXX-pci devices are not what are they called as they
>> simply create underlying virtio-bus, attach a real virtio-XXXX-device
>> there
>> (which is not PCI) and only then attach disk to non-PCI virtio device.
> Hi,
>
> Seems it's a bug: il should be compatible with the old virtio-scsi-pci.
> What's the meaning of the "0" in drive_add command?
It is a PCI slot number, the complete address would include a domain and
a bus.
> Fred
>>
>> So as I see there is no way to attach a disk to an existing controller in
>> already running qemu.
>>
>> This is how I add disks to qemu now:
>> -device virtio-scsi-pci,id=virtioscsi0 \
>> -drive file=virtimg/fc18guest,if=none,id=drive0,readonly=off,
>> format=raw,media=disk,werror=stop,rerror=stop \
>> -device scsi-disk,id=scsidisk0,bus=virtioscsi0.0,channel=0,
>> scsi-id=0,lun=0,drive=drive0,removable=off \
>>
>> I want to only add "-device virtio-scsi-pci,id=virtioscsi0" to the
>> command
>> line and do the rest from the qemu console.
>>
>> Am I missing some useful command from qemu console or anything else?
>> Thanks!
--
With best regards
Alexey Kardashevskiy -- icq: 52150396
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible?
2013-06-06 13:59 ` Alexey Kardashevskiy
@ 2013-06-06 14:29 ` Frederic Konrad
2013-06-07 0:05 ` Alexey Kardashevskiy
2013-06-07 3:40 ` Alexey Kardashevskiy
0 siblings, 2 replies; 6+ messages in thread
From: Frederic Konrad @ 2013-06-06 14:29 UTC (permalink / raw)
To: Alexey Kardashevskiy; +Cc: qemu-devel@nongnu.org, Michael S. Tsirkin
On 06/06/2013 15:59, Alexey Kardashevskiy wrote:
> On 06.06.2013 22:44, Frederic Konrad wrote:
>> On 06/06/2013 12:13, Alexey Kardashevskiy wrote:
>>> Hi!
>>>
>>> For the pseries platform (server PPC64) we do not support PCI hotplug
>>> yet.
>>> However we still want to hot plug disks.
>>>
>>> As a workaround, we could add multiple SCSI host devices
>>> (virtio-scsi-pci,
>>> spapr-vscsi) without any disk attached and later (using qemu console)
>>> attach drives to them as we do with the "-drive" parameter in the
>>> command line.
>>>
>>> So I enabled CONFIG_PCI_HOTPLUG_OLD=y and tried.
>>>
>>> However, drive_add console command works only with PCI what eliminates
>>> "spapr-vscsi" from the list. Oookay.
>>>
>>> Then I tried running qemu with "-device virtio-scsi-pci,id=device0" and
>>> later doing "drive_add 0 file=virtimg/test1" from the qemu console. This
>>> time qemu responded with "Device is not a SCSI adapter" what is
>>> correct as
>>> nowadays virtio-XXXX-pci devices are not what are they called as they
>>> simply create underlying virtio-bus, attach a real virtio-XXXX-device
>>> there
>>> (which is not PCI) and only then attach disk to non-PCI virtio device.
>> Hi,
>>
>> Seems it's a bug: il should be compatible with the old virtio-scsi-pci.
>> What's the meaning of the "0" in drive_add command?
> It is a PCI slot number, the complete address would include a domain and
> a bus.
>
>
Ok thanks, I'll take a look.
>> Fred
>>> So as I see there is no way to attach a disk to an existing controller in
>>> already running qemu.
>>>
>>> This is how I add disks to qemu now:
>>> -device virtio-scsi-pci,id=virtioscsi0 \
>>> -drive file=virtimg/fc18guest,if=none,id=drive0,readonly=off,
>>> format=raw,media=disk,werror=stop,rerror=stop \
>>> -device scsi-disk,id=scsidisk0,bus=virtioscsi0.0,channel=0,
>>> scsi-id=0,lun=0,drive=drive0,removable=off \
This two last command isn't available in the monitor?
>>>
>>> I want to only add "-device virtio-scsi-pci,id=virtioscsi0" to the
>>> command
>>> line and do the rest from the qemu console.
>>>
>>> Am I missing some useful command from qemu console or anything else?
>>> Thanks!
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible?
2013-06-06 14:29 ` Frederic Konrad
@ 2013-06-07 0:05 ` Alexey Kardashevskiy
2013-06-07 3:40 ` Alexey Kardashevskiy
1 sibling, 0 replies; 6+ messages in thread
From: Alexey Kardashevskiy @ 2013-06-07 0:05 UTC (permalink / raw)
To: Frederic Konrad; +Cc: qemu-devel@nongnu.org, Michael S. Tsirkin
On 07.06.2013 0:29, Frederic Konrad wrote:
> On 06/06/2013 15:59, Alexey Kardashevskiy wrote:
>> On 06.06.2013 22:44, Frederic Konrad wrote:
>>> On 06/06/2013 12:13, Alexey Kardashevskiy wrote:
>>>> Hi!
>>>>
>>>> For the pseries platform (server PPC64) we do not support PCI hotplug
>>>> yet.
>>>> However we still want to hot plug disks.
>>>>
>>>> As a workaround, we could add multiple SCSI host devices
>>>> (virtio-scsi-pci,
>>>> spapr-vscsi) without any disk attached and later (using qemu console)
>>>> attach drives to them as we do with the "-drive" parameter in the
>>>> command line.
>>>>
>>>> So I enabled CONFIG_PCI_HOTPLUG_OLD=y and tried.
>>>>
>>>> However, drive_add console command works only with PCI what eliminates
>>>> "spapr-vscsi" from the list. Oookay.
>>>>
>>>> Then I tried running qemu with "-device virtio-scsi-pci,id=device0" and
>>>> later doing "drive_add 0 file=virtimg/test1" from the qemu console.
>>>> This
>>>> time qemu responded with "Device is not a SCSI adapter" what is
>>>> correct as
>>>> nowadays virtio-XXXX-pci devices are not what are they called as they
>>>> simply create underlying virtio-bus, attach a real virtio-XXXX-device
>>>> there
>>>> (which is not PCI) and only then attach disk to non-PCI virtio device.
>>> Hi,
>>>
>>> Seems it's a bug: il should be compatible with the old virtio-scsi-pci.
>>> What's the meaning of the "0" in drive_add command?
>> It is a PCI slot number, the complete address would include a domain and
>> a bus.
>>
>>
>
> Ok thanks, I'll take a look.
>>> Fred
>>>> So as I see there is no way to attach a disk to an existing
>>>> controller in
>>>> already running qemu.
>>>>
>>>> This is how I add disks to qemu now:
>>>> -device virtio-scsi-pci,id=virtioscsi0 \
>>>> -drive file=virtimg/fc18guest,if=none,id=drive0,readonly=off,
>>>> format=raw,media=disk,werror=stop,rerror=stop \
>>>> -device scsi-disk,id=scsidisk0,bus=virtioscsi0.0,channel=0,
>>>> scsi-id=0,lun=0,drive=drive0,removable=off \
>
> This two last command isn't available in the monitor?
-device is (looks like) but did not look further as drive_add (which I
thought as an analog of "-drive") is not exactly the same and I cannot
add disks without it anyway.
>>>>
>>>> I want to only add "-device virtio-scsi-pci,id=virtioscsi0" to the
>>>> command
>>>> line and do the rest from the qemu console.
>>>>
>>>> Am I missing some useful command from qemu console or anything else?
>>>> Thanks!
>>
>
--
With best regards
Alexey Kardashevskiy -- icq: 52150396
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible?
2013-06-06 14:29 ` Frederic Konrad
2013-06-07 0:05 ` Alexey Kardashevskiy
@ 2013-06-07 3:40 ` Alexey Kardashevskiy
1 sibling, 0 replies; 6+ messages in thread
From: Alexey Kardashevskiy @ 2013-06-07 3:40 UTC (permalink / raw)
To: Frederic Konrad; +Cc: qemu-devel@nongnu.org, Michael S. Tsirkin
On 06/07/2013 12:29 AM, Frederic Konrad wrote:
> On 06/06/2013 15:59, Alexey Kardashevskiy wrote:
>> On 06.06.2013 22:44, Frederic Konrad wrote:
>>> On 06/06/2013 12:13, Alexey Kardashevskiy wrote:
>>>> Hi!
>>>>
>>>> For the pseries platform (server PPC64) we do not support PCI hotplug
>>>> yet.
>>>> However we still want to hot plug disks.
>>>>
>>>> As a workaround, we could add multiple SCSI host devices
>>>> (virtio-scsi-pci,
>>>> spapr-vscsi) without any disk attached and later (using qemu console)
>>>> attach drives to them as we do with the "-drive" parameter in the
>>>> command line.
>>>>
>>>> So I enabled CONFIG_PCI_HOTPLUG_OLD=y and tried.
>>>>
>>>> However, drive_add console command works only with PCI what eliminates
>>>> "spapr-vscsi" from the list. Oookay.
>>>>
>>>> Then I tried running qemu with "-device virtio-scsi-pci,id=device0" and
>>>> later doing "drive_add 0 file=virtimg/test1" from the qemu console. This
>>>> time qemu responded with "Device is not a SCSI adapter" what is
>>>> correct as
>>>> nowadays virtio-XXXX-pci devices are not what are they called as they
>>>> simply create underlying virtio-bus, attach a real virtio-XXXX-device
>>>> there
>>>> (which is not PCI) and only then attach disk to non-PCI virtio device.
>>> Hi,
>>>
>>> Seems it's a bug: il should be compatible with the old virtio-scsi-pci.
>>> What's the meaning of the "0" in drive_add command?
>> It is a PCI slot number, the complete address would include a domain and
>> a bus.
>>
>>
>
> Ok thanks, I'll take a look.
>>> Fred
>>>> So as I see there is no way to attach a disk to an existing controller in
>>>> already running qemu.
>>>>
>>>> This is how I add disks to qemu now:
>>>> -device virtio-scsi-pci,id=virtioscsi0 \
>>>> -drive file=virtimg/fc18guest,if=none,id=drive0,readonly=off,
>>>> format=raw,media=disk,werror=stop,rerror=stop \
>>>> -device scsi-disk,id=scsidisk0,bus=virtioscsi0.0,channel=0,
>>>> scsi-id=0,lun=0,drive=drive0,removable=off \
>
> This two last command isn't available in the monitor?
>>>>
>>>> I want to only add "-device virtio-scsi-pci,id=virtioscsi0" to the
>>>> command
>>>> line and do the rest from the qemu console.
>>>>
>>>> Am I missing some useful command from qemu console or anything else?
>>>> Thanks!
This works (thanks to Anthony):
./qemu-system-ppc64 \
-L "qemu-ppc64-bios/" \
-nodefaults \
-chardev "stdio,id=char1,signal=off,mux=on" \
-device "spapr-vty,id=ser1,chardev=char1" \
-mon "chardev=char1,mode=readline,id=mon1" \
-m "1024" \
-machine "pseries" \
-nographic \
-vga "none" \
-enable-kvm \
-kernel "guest.vmlinux.n" \
-initrd "1.cpio" \
-device "virtio-scsi-pci,id=foo"
And then issue 2 commands in the qemu console:
drive_add auto file=virtimg/fc18guest,if=none,id=bar
device_add scsi-disk,bus=foo.0,drive=bar,unit=0
The guest is even able to autodetect new volume. Profit.
--
Alexey
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-06-07 3:41 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-06-06 10:13 [Qemu-devel] [QEMU question] Disk hot plugging without working PCI hotplug - possible? Alexey Kardashevskiy
2013-06-06 12:44 ` Frederic Konrad
2013-06-06 13:59 ` Alexey Kardashevskiy
2013-06-06 14:29 ` Frederic Konrad
2013-06-07 0:05 ` Alexey Kardashevskiy
2013-06-07 3:40 ` Alexey Kardashevskiy
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