public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: David Ahern <dsahern@gmail.com>
To: Alex Davis <alex14641@yahoo.com>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, kvm@vger.kernel.org
Subject: Re: CD-ROM size not updated when switching CD-ROM images.
Date: Wed, 20 Oct 2010 10:44:15 -0600	[thread overview]
Message-ID: <4CBF1C5F.1070406@gmail.com> (raw)
In-Reply-To: <511807.4805.qm@web50208.mail.re2.yahoo.com>



On 10/19/10 18:03, Alex Davis wrote:

>> You ejected the CD-ROM on the QEMU side, the guest doesn't
>> necessarily
>> know about the medium change.  What happens when you
>> use "eject
>> /dev/sr0" inside the guest instead?
> I get a 'no medium found' error from the 'dd..' command. After
> going into the the monitor, ejecting and reloading the disk, 
> I still get the size of the first disk in the guest.

As I recall the old data is coming from the host page cache; it is not
seeing the media change. Try dropping the cache in the host on a media
change (echo 3 > /proc/sys/vm/drop_caches) or modify qemu to close and
reopen the cdrom device.

David


>>
>> I don't know how CD-ROM media change works on real
>> hardware, but that
>> is the behavior that QEMU should be following.
>>
>> Stefan
> 
> 
>       
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

  reply	other threads:[~2010-10-20 16:44 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-10-19  3:43 CD-ROM size not updated when switching CD-ROM images Alex Davis
2010-10-19  8:31 ` Stefan Hajnoczi
2010-10-20  0:03   ` Alex Davis
2010-10-20 16:44     ` David Ahern [this message]
2010-10-20 23:28       ` Alex Davis
2010-10-30 20:32       ` Alex Davis
  -- strict thread matches above, loose matches on Subject: below --
2010-10-20 12:50 Alex Davis
2010-10-30 21:24 Alex Davis

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4CBF1C5F.1070406@gmail.com \
    --to=dsahern@gmail.com \
    --cc=alex14641@yahoo.com \
    --cc=kvm@vger.kernel.org \
    --cc=stefanha@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox