Re: [Qemu-devel] [Bug 670769] Re: CDROM size not updated when changing image files

[Alex Davis]

I code, therefore I am


--- On Tue, 11/9/10, agraf <address@hidden> wrote:

> From: agraf <address@hidden>
> Subject: Re: [Qemu-devel] [Bug 670769] Re: CDROM size not updated when 
> changing image files
> To: address@hidden
> Date: Tuesday, November 9, 2010, 10:47 PM
> 
> On 10.11.2010, at 04:17, Alex Davis wrote:
> 
> > Please note that until this bug is fixed, one cannot
> successfully
> > install a guest OS from a set of CD-ROMS where the
> first disk image is
> > smaller than subsequent ones.
> > 
> > -- 
> > CDROM size not updated when changing image files
> > https://bugs.launchpad.net/bugs/670769
> > You received this bug notification because you are a
> member of qemu-
> > devel-ml, which is subscribed to QEMU.
> > 
> > Status in QEMU: New
> > 
> > Bug description:
> > I'm using qemu 13.0 with a plain Linux kernel using
> the ata_piix driver as the guest, and an initrd that starts
> a shell. When changing the image in the monitor and reading
> from the CDROM in the guest, the size is not updated. I'm
> using LInux 2.6.32.24
> > as the host and I've tested 2.6.32.24, 2.6.35, and
> 2.6.36 as guests.  Both host and guest are 64-bit. Here
> is the command used to start the guest using the initrd:
> > 
> > ./x86_64-softmmu/qemu-system-x86_64 -cdrom
> /spare2/cd1.img -kernel
> /sources/linux-2.6.32.24-test/arch/x86/boot/bzImage -initrd
> /spare2/initrd.img -append 'root=/dev/ram0 rw' -cpu
> core2duo
> > 
> > Additional info on this bug can be found here: 
> > http://marc.info/?l=kvm&m=128746013906820&w=2. Note:
> this is how I discovered 
> > the bug, using 32-bit Slackware install CDs.
> > 
> > I'm attaching the initrd I used in my tests: I created
> two different-sized fake CDROM images by dd'ing from
> /dev/zero. In my tests,
> > cd1.img is smaller that cd2.img. In the monitor I
> executed 'change ide1-cd0 /spare2/cd2.img' to load the new
> image. I checked 
> > the size by cat'ing /sys/block/sr0/size in the guest
> after reading the CDROM. Reading the CDROM was done by
> typing
> > 'dd if=/dev/sr0 of=/dev/null bs=512 count=3'
> 
> Just to clarify, the contents of the image do change, but
> the reported
> size does not?
Correct?

-- 
CDROM size not updated when changing image files
https://bugs.launchpad.net/bugs/670769
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.

Status in QEMU: New

Bug description:
I'm using qemu 13.0 with a plain Linux kernel using the ata_piix driver as the 
guest, and an initrd that starts a shell. When changing the image in the 
monitor and reading from the CDROM in the guest, the size is not updated. I'm 
using LInux 2.6.32.24
as the host and I've tested 2.6.32.24, 2.6.35, and 2.6.36 as guests.  Both host 
and guest are 64-bit. Here is the command used to start the guest using the 
initrd:

./x86_64-softmmu/qemu-system-x86_64 -cdrom /spare2/cd1.img -kernel 
/sources/linux-2.6.32.24-test/arch/x86/boot/bzImage -initrd /spare2/initrd.img 
-append 'root=/dev/ram0 rw' -cpu core2duo

Additional info on this bug can be found here: 
http://marc.info/?l=kvm&m=128746013906820&w=2. Note: this is how I discovered 
the bug, using 32-bit Slackware install CDs.

I'm attaching the initrd I used in my tests: I created two different-sized fake 
CDROM images by dd'ing from /dev/zero. In my tests,
cd1.img is smaller that cd2.img. In the monitor I executed 'change ide1-cd0 
/spare2/cd2.img' to load the new image. I checked 
the size by cat'ing /sys/block/sr0/size in the guest after reading the CDROM. 
Reading the CDROM was done by typing
'dd if=/dev/sr0 of=/dev/null bs=512 count=3'