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Date: Tue, 11 Jan 2011 09:00:05 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 28/35] kvm: x86: Introduce kvmclock device
	to save/restore its state
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To: Jan Kiszka <jan.kiszka@web.de>
Cc: Anthony Liguori <aliguori@us.ibm.com>, kvm@vger.kernel.org, Glauber Costa <glommer@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org

On 01/10/2011 11:21 PM, Jan Kiszka wrote:
> Am 10.01.2011 22:06, Jan Kiszka wrote:
>>>   kvmclock should be created with
>>> kvm_state as a parameter and kvm_vm_ioctl() is passed the stored
>>> reference.   Taking a global reference to kvm_state in machine_init is
>>> not a bad thing, obviously the machine initialization function needs
>>> access to the kvm_state.
>>
>> This would also require changing sysbus interfaces for the sake of KVM's
>> "abstraction". If this is the only way forward, I could look into this.
>
> Actually, there is already a channel to pass pointers to qdev devices:
> the pointer property hack. I'm not sure we should contribute to its user
> base or take the chance for a cleanup, but we are not alone with this
> requirement. Point below remains valid, though.

The pointer property uses, at least last time I checked, were all:

1) for a CPU (apic, etrax interrupt controller)

2) for a device (sparc IIRC)

3) useless (smbus_eeprom.c)

So adding a fourth kind is not really a good idea, I think.

Paolo