Re: [Qemu-devel] [PATCH] iSCSI: add configuration variables for iSCSI

[ronnie sahlberg]

I do recognize that there is real need to provide password to iscsi
(and rbd?) via the monitor.
I myself do not use libvirt (it is just too much pain to be worth it
to try to upgrade it out-of-step with your distribution)
but I recognize that likely vast majority of users would use libvirt.


Once consensus is reached on "how to handle devices that need
two-stage setup" and what it would look like
I can volunteer to implement it. It would however be way out of scope
of and bigger than a simple iscsi-local patch


What about the idea about splitting .open() into two stages:
.open()   /* stage one, called before -S monitor is invoked */
.open_stage_2() /* called after -S finishes and when it starts to boot
the guest CPU */

?



regards
ronnie sahlberg


On Fri, Dec 23, 2011 at 8:08 PM, Paolo Bonzini <address@hidden> wrote:
> On 12/22/2011 09:51 PM, ronnie sahlberg wrote:
>>
>> The difference between qcow2 and iscsi and the problem is that .open()
>> is called for all devices before the monitor is started, so .open() is
>> called before we would have a chance to even hand the password to
>> qemu.
>>
>> For qcow2 this is not a problem since even if the file is password
>> protected the file header is not, so you can still open the file and
>> read the header (to discover it is password protected) without knowing
>> the password.
>> So qcow2 can still open the file and do all the sanity checks it needs
>> without yet knowing the password.
>
>
> You're right.
>
> I see that the libvirt driver for rbd simply passes it on the command line.
>  I hope I'll be able to review the patch further today.
>
> Paolo