Red Hat Bugzilla – Bug 735993
configuring a SCSI cd-rom in an HVM domain messes up IDE drives
Last modified: 2012-02-21 00:55:54 EST
When adding a disk with sda:cdrom to an HVM domain, the media type is set on the wrong disk: sda-sdd set the media type on hda-hdd, while from sde on the actual disk is off by 4 (i.e. sde sets it on sda and so on). This is bad because adding a SCSI cd-rom can make the whole domain unbootable or crash qemu-dm. * configuration for unbootable domain: disk = ["file:/var/lib/xen/hvm.img,hda,w", "file:/var/lib/xen/cd.iso,sda:cdrom,r"] boot = "c" (hda becomes a CD-ROM and it is excluded from the boot sequence) * configuration for qemu-dm crash: disk = ["file:/var/lib/xen/hvm.img,hda,w", "file:/var/lib/xen/cd.iso,sdb:cdrom,r"] (the hint is set on sdb and this causes a NULL-pointer dereference). The bug is present since "always".
Fix built into xen-3.0.3-134.el5
reproduce the bug on xen-3.0.3-132.el5 and verify the bug on xen-3.0.3-135.el5. on xen-3.0.3-132.el5, boot the HVM guest with configure: disk = ["file:/var/lib/xen/hvm.img,hda,w", "file:/var/lib/xen/cd.iso,sda:cdrom,r"] boot = "c" In fact, no guest is created. boot the HVM guest with configure: disk = ["file:/var/lib/xen/hvm.img,hda,w", "file:/var/lib/xen/cd.iso,sdb:cdrom,r"] the guest fail to boot. on xen-3.0.3-135.el5: boot the guest with both configure will succeed, and the content of iso can be seen in the guest. So change the bug to VERIFIED.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHBA-2012-0160.html