Re: [libvirt] Re: [Qemu-devel] [PATCH 1/6] Allow multiple monitor devices (v2)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Daniel P. Berrange wrote:
> On Tue, Apr 14, 2009 at 12:15:23PM +0300, Avi Kivity wrote:
>> Daniel P. Berrange wrote:
>>> Yes indeed its a little crazy :-)  As anthony mentioned if libvirt were 
>>> able to be notified of changes a user makes in the monitor, there's no 
>>> reason we could not allow end users to access the monitor of a VM 
>>> libvirt is managing. We just need to make sure libvirt doesn't miss
>>> changes like attaching or detaching block devices, etc, because that'll
>>> cause crash/data loss later when libvirt migrates or does save/restore,
>>> etc because it'll launch QEMU with wrong args
>>>  
>> You still have an inherent race here.
>>
>> user: plug in disk
>> libvirt: start migration, still without disk
>> qemu: libvirt, a disk has been plugged in.
> 
> That is true, but we'd still be considering direct monitor access to
> be a 'expert' user mode of use. If they wish to shoot themselves in
> the foot by triggering a migration at same time they are hotplugging
> I'm fine if their whole leg gets blown away.  

...while there is also nothing that speaks against blocking any device
hot-plugging while migration is ongoing. Independent of if there is some
management app involved or the user himself plays with multiple monitors.

Jan

-- 
Siemens AG, Corporate Technology, CT SE 2
Corporate Competence Center Embedded Linux

--
Libvir-list mailing list
Libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list

[Index of Archives]     [Virt Tools]     [Libvirt Users]     [Lib OS Info]     [Fedora Users]     [Fedora Desktop]     [Fedora SELinux]     [Big List of Linux Books]     [Yosemite News]     [KDE Users]     [Fedora Tools]