Re: [Qemu-devel] [PATCH v2 3/3] raw-posix: Re-open host CD-ROM after media change

[Amit Shah <amit.shah@redhat.com>]

On (Tue) 05 Apr 2011 [10:48:16], Avi Kivity wrote:
> On 04/05/2011 09:41 AM, Amit Shah wrote:
> >See http://www.spinics.net/lists/linux-scsi/msg51504.html
> 
> I see this is quite fresh.  What are the plans here?

We're still discussing where the fix should be, but it certainly is a
kernel bug and should be fixed there, and then applied to stable.

However, there are other bugs in qemu which will prevent the right
size changes to be visible in the guest (the RFC series I sent out
earlier in this thread need to be applied to QEMU at the least, the
series has grown in my development tree since the time I sent that one
out).  So essentially we need to update both, the hypervisor and the
guest to get proper CDROM media change support.

It also looks like we can't have a workaround in QEMU to get older
guests to work.

However, a hack in the kernel can be used without any QEMU changes
(revalidate disk on each sr_open() call, irrespective of detecting any
media change).  I'm against doing that for upstream, but downstreams
could do that for new guest - old hypervisor compat.

		Amit