Re: [Qemu-arm] [Qemu-devel] Question about a qemu Aarch64 error when adding several SCSI disks

[Kevin Zhao]

On 28 June 2016 at 02:23, Cole Robinson <address@hidden> wrote:

On 06/27/2016 09:05 AM, Kevin Zhao wrote:
> Hi Cole,
>
> On 24 June 2016 at 19:35, Cole Robinson <address@hidden> wrote:
>
>> On 06/24/2016 12:58 AM, Kevin Zhao wrote:
>>> Hi Peter,
>>>      Follow your advice, I have complied the Qemu v2.6.
>>> address@hidden:~$ kvm --version
>>> QEMU emulator version 2.6.50 (v2.6.0-1280-g6f1d2d1-dirty), Copyright (c)
>>> 2003-2008 Fabrice Bellard
>>>      With this newest version, I use virt-manager to create the guest ,
>> the
>>> xml file is in the attachment. But the Qemu return error when creating:
>>>      *error: internal error: process exited while connecting to monitor:
>>> qemu-system-aarch64: -device
>>> pci-bridge,chassis_nr=2,id=pci,bus=pci,addr=0x1: Duplicate ID 'pci' for
>>> device*
>>>
>>
>> That's probably this libvirt issue fixed in 1.3.4 and later:
>>
>> https://www.redhat.com/archives/libvirt-users/2016-April/msg00030.html
>>
>> I suggest testing with libvirt.git as well, there's been aarch64 related
>> patches trickling in regularly
>>
>> - Cole
>>
>>      Thanks for your valuable advice. Follow your advice, I have build the
> upstream vesion
> of libvirt. The libvirt  version is :
>        address@hidden:/opt/stack/kevin/libvirt/daemon# ./libvirtd
>         2016-06-27 12:11:03.501+0000: 28044: info : libvirt version: 2.0.0
> I stopped the system libvirtd-bin and libvirt-guests , then using libvirtd
> above.
>
> Also I have replace the system Qemu with the Qemu 2.6.50 which I have built
> from upstream :
>        address@hidden:/opt/stack/kevin/libvirt# qemu-system-aarch64 --version
>         QEMU emulator version 2.6.50 (v2.6.0-1280-g6f1d2d1-dirty),
> Copyright (c) 2003-2008 Fabrice Bellard
> Using this XML in the attachment:
>         Then Run virsh command to create guest:
>        address@hidden:/opt/stack/kevin/libvirt/tools# ./virsh create
> /opt/stack/f23.xml --console
>         error: Failed to create domain from /opt/stack/f23.xml
>         error: internal error: process exited while connecting to monitor:
> 2016-06-27T12:45:23.807405Z qemu-system-aarch64: -drive
> file=/var/lib/libvirt/qemu/nvram/f23_VARS.fd,if=pflash,format=raw,unit=1:
> Could not open         '/var/lib/libvirt/qemu/nvram/f23_VARS.fd':
> Permission denied
>
> Here I met the permission problem and I'm not sure where is wrong. If I use
> origin qemu-system-aarch64(installed by apt-get),I will not meet the
> problem of permission..Kindly need your help, you will be really
> appreciated,,,   :D
> $ls -l /usr/bin/qemu-system-aarch64
> -rwxr-xr-x 1 root root 26935520 Jun 27 10:56 /usr/bin/qemu-system-aarch64
>  $ls -l /var/lib/libvirt/qemu/nvram/f23_VARS.fd
> -rw------- 1 root root 67108864 Jun 20 07:27
> /var/lib/libvirt/qemu/nvram/f23_VARS.fd
>
>
>

Depending on how you compiled libvirt, it may run qemu as the unprivileged
qemu:qemu user. Perhaps that VM was created with the default compilation
options to run qemu as root:root, and whatever you are trying to run it with
now is using qemu:qemu

Yeah it really the problem with privilege. I change the /var/lib/libvirt/qemu/nvram/f23_VARS.fd

 to another directory so that qemu can access it,and no permission denied error 

again.

Thank Cole.

All:

     With the Qemu 2.6.50 and libvirt(commit 03ce1328086d6937d2647d616efff29941a3e80a):

I find that the problem that I have met before occurs again. I can reproduce it.

     1.  After launching a VM with fedora23(for example), the xml is f23.xml in attachment.

     2. Then  use qemu-img command to generate a qemu disk f23-2.qcow2 and f23-3.qcow2

     3. Add f23-2.qcow2 as sdc.

     $ ./virsh  attach-device  f23  /root/sdc.xml

sdc.xml :

    <disk type="file" device="disk">

       <driver name="qemu" type="qcow2"/>

      <source file="/var/lib/libvirt/images/f23-2.qcow2"/>

      <target dev="sdc" bus="scsi"/>

    </disk>

     Then in the Guest f23, we can see it takes effect immediately.

     4. Add f23-3.qcow2  as sdh , also add virtio-scsi controller for sdh.

      $ ./virsh edit f23

      add this below

      <controller type="scsi" index="1" model="virtio-scsi"/>

        <disk type="file" device="disk">

      <driver name="qemu" type="qcow2"/>

      <source file="/var/lib/libvirt/images/f23-4.qcow2"/>

      <target dev="sdh" bus="scsi"/>

    </disk>

      $ ./virsh destory f23  && ./.virsh start f23

Got the error:

2016-06-28 11:37:17.017+0000: 6329: warning : qemuDomainObjTaint:3227 : Domain id=15 name='f23' uuid=e2de65f4-5d9a-4b90-a56a-ae40f4763aec is tainted: high-privileges

2016-06-28 11:37:17.017+0000: 6329: warning : qemuDomainObjTaint:3227 : Domain id=15 name='f23' uuid=e2de65f4-5d9a-4b90-a56a-ae40f4763aec is tainted: host-cpu

2016-06-28 11:37:28.546+0000: 6313: error : qemuMonitorIORead:583 : Unable to read from monitor: Connection reset by peer

2016-06-28 11:37:28.546+0000: 6313: error : qemuProcessReportLogError:1815 : internal error: qemu unexpectedly closed the monitor: qemu-system-aarch64: /opt/stack/kevin/qemu/migration/savevm.c:615: vmstate_register_with_alias_id: Assertion `!se->compat || se->instance_id == 0' failed.

So this bug seems exist with new qemu and new libvirt. 

- Cole

f23.xml
Description: Text Data