Re: [Qemu-devel] CD-ROM bug round-up

[Stefan Hajnoczi <stefanha@gmail.com>]

On Wed, Mar 30, 2011 at 5:50 PM, Gleb Natapov <gleb@redhat.com> wrote:
> On Wed, Mar 30, 2011 at 05:40:40PM +0100, Stefan Hajnoczi wrote:
>> = Anthony =
>>
>> Using 'change' or scripted commands without a delay between closing
>> the BlockDriverState and opening the new CD-ROM.  The guest does not
>> have a chance to poll the drive and determine a medium present ->
>> medium not present transition followed by a medium not present ->
>> medium present transition.
>>
>> A fix for this does not exist yet and might be tricky since we need to
>> delay or wait for the guest to poll once before opening the new
>> CD-ROM.
>>
> This sounds familiar and should have been fixed by commit
> 93c8cfd9e67a62711b86f4c93747566885eb7928

Excellent, thanks for pointing this out.  We need to figure out
whether this mechanism is insufficient for some guests.

On a Windows-related note, I've found that Windows 2003 Server sends
START STOP UNIT to eject the medium without unlocking the tray first.
When the CD-ROM is passed through to a Linux host CD-ROM drive the
eject ioctl fails if the tray is locked.  I haven't investigated this
more yet.

Stefan