Re: [Qemu-devel] [Bug 1195170] Re: cpu hot-add doesn't work with upstream qemu 1.5.50

[chandrashekar shastri <cshastri@linux.vnet.ibm.com>]

Ok. Thanks.

On 06/27/2013 02:39 PM, Paolo Bonzini wrote:
> Il 27/06/2013 11:03, chandrashekar shastri ha scritto:
>> Hi Bonzini,
>>
>> Thanks, cpu hot-plug is working.
>> Could you please help me with cpu hot-unplug It is working.
> It is not implemented yet.
>
> Paolo
>

-- 
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1195170

Title:
  cpu hot-add doesn't work with upstream qemu 1.5.50

Status in QEMU:
  Invalid

Bug description:
  cpu hot-add doesn't work with upstream qemu 1.5.50. When we add the
  cpu [through QMP] it throws error as " {"error": {"class":
  "GenericError", "desc": "Unable to add CPU: 2, max allowed: 1"}} ",
  when we have booted the guest with two cpus.

  Host Kernel Version: 3.10.0-rc5+

  Libvirt Version: 1.0.6

  Qemu Version: 1.5.50

  Guest Kernel : 2.6.32-358.6.1.el6.x86_64

  
  Steps to Reproduce :

  Boot the guest with : qemu-system-x86_64 -drive
  file='/home/images/vm1.qcow2',format=qcow2,cache=none,boot=on -m 2048
  -smp 2,cores=2,threads=1,sockets=1 -qmp tcp:localhost:4444,server
  -monitor stdio -enable-kvm

  Start the  telnet localhost 4444 on another shell

  verify that there are two cpus :

  I verified through HMP 
  (qemu) info cpus 
  * CPU #0: pc=0x000000000000f081 thread_id=2034
    CPU #1: pc=0x00000000000f6497 (halted) thread_id=2031

  Hot add the CPU using the below command in QMP:

  { "execute": "cpu-add", "arguments": { "id": 2 } }
  {"error": {"class": "GenericError", "desc": "Unable to add CPU: 2, max allowed: 1"}}

  Notes:
  --------
  1. By default [without specifying the no of cpu], the guest boots up with 1 cpu, when we try to add one more cpu, below is the error:

  { "execute": "cpu-add", "arguments": { "id": 1 } }
  {"error": {"class": "GenericError", "desc": "Unable to add CPU: 1, max allowed: 0"}}

  2. This issue is seen with or without enabling the KVM [i.e booting
  the guest without -enable-kvm option]

To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1195170/+subscriptions