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* KVM_CREATE_VCPU max vcpu ABI
@ 2011-05-07 10:16 Pekka Enberg
  2011-05-07 11:12 ` Jan Kiszka
  0 siblings, 1 reply; 3+ messages in thread
From: Pekka Enberg @ 2011-05-07 10:16 UTC (permalink / raw)
  To: Avi Kivity, KVM General, Ingo Molnar, Asias He, Cyrill Gorcunov,
	Sasha Levin <levin

Hi!

Documentation/kvm/api.txt says the following:

  4.6 KVM_CREATE_VCPU

  Capability: basic
  Architectures: all
  Type: vm ioctl
  Parameters: vcpu id (apic id on x86)
  Returns: vcpu fd on success, -1 on error

  This API adds a vcpu to a virtual machine.  The vcpu id is a small integer
  in the range [0, max_vcpus).

However, max_vcpus is not specified and I am unable to find ioctl()
which I could use to look it up. Is it specified somewhere? We can, of
course, attempt to create as many VCPUs as possible until
KVM_CREATE_VCPU returns EINVAL...

                        Pekka

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: KVM_CREATE_VCPU max vcpu ABI
  2011-05-07 10:16 KVM_CREATE_VCPU max vcpu ABI Pekka Enberg
@ 2011-05-07 11:12 ` Jan Kiszka
  2011-05-07 14:48   ` Pekka Enberg
  0 siblings, 1 reply; 3+ messages in thread
From: Jan Kiszka @ 2011-05-07 11:12 UTC (permalink / raw)
  To: Pekka Enberg
  Cc: Avi Kivity, KVM General, Ingo Molnar, Asias He, Cyrill Gorcunov,
	Sasha Levin

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On 2011-05-07 12:16, Pekka Enberg wrote:
> Hi!
> 
> Documentation/kvm/api.txt says the following:
> 
>   4.6 KVM_CREATE_VCPU
> 
>   Capability: basic
>   Architectures: all
>   Type: vm ioctl
>   Parameters: vcpu id (apic id on x86)
>   Returns: vcpu fd on success, -1 on error
> 
>   This API adds a vcpu to a virtual machine.  The vcpu id is a small integer
>   in the range [0, max_vcpus).
> 
> However, max_vcpus is not specified and I am unable to find ioctl()
> which I could use to look it up. Is it specified somewhere? We can, of
> course, attempt to create as many VCPUs as possible until
> KVM_CREATE_VCPU returns EINVAL...

Querying for KVM_CAP_NR_VCPUS returns this number (documented in the kvm
header). Want to file a patch for adding a hint to the section above?

Jan


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^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: KVM_CREATE_VCPU max vcpu ABI
  2011-05-07 11:12 ` Jan Kiszka
@ 2011-05-07 14:48   ` Pekka Enberg
  0 siblings, 0 replies; 3+ messages in thread
From: Pekka Enberg @ 2011-05-07 14:48 UTC (permalink / raw)
  To: Jan Kiszka
  Cc: Avi Kivity, KVM General, Ingo Molnar, Asias He, Cyrill Gorcunov,
	Sasha Levin

On Sat, 2011-05-07 at 13:12 +0200, Jan Kiszka wrote:
> On 2011-05-07 12:16, Pekka Enberg wrote:
> > Hi!
> > 
> > Documentation/kvm/api.txt says the following:
> > 
> >   4.6 KVM_CREATE_VCPU
> > 
> >   Capability: basic
> >   Architectures: all
> >   Type: vm ioctl
> >   Parameters: vcpu id (apic id on x86)
> >   Returns: vcpu fd on success, -1 on error
> > 
> >   This API adds a vcpu to a virtual machine.  The vcpu id is a small integer
> >   in the range [0, max_vcpus).
> > 
> > However, max_vcpus is not specified and I am unable to find ioctl()
> > which I could use to look it up. Is it specified somewhere? We can, of
> > course, attempt to create as many VCPUs as possible until
> > KVM_CREATE_VCPU returns EINVAL...
> 
> Querying for KVM_CAP_NR_VCPUS returns this number (documented in the kvm
> header). Want to file a patch for adding a hint to the section above?

Done. Thanks Jan!


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2011-05-07 14:48 UTC | newest]

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2011-05-07 10:16 KVM_CREATE_VCPU max vcpu ABI Pekka Enberg
2011-05-07 11:12 ` Jan Kiszka
2011-05-07 14:48   ` Pekka Enberg

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