+++ This bug was initially created as a clone of Bug #609422 +++

Description of problem:
If you use the virtual machine manager GUI to add a disk to a VM, it works fine. If you do it via cli, it adds an extra line that causes the VM not to boot.
Version-Release number of selected component (if applicable):
RHEL 5.5
libvirt-0.6.3-33.el5

How reproducible:
100%

Steps to Reproduce:
1. start a VM ('test')
2. add a disk using vish like this: 
   virsh attach-disk test /dev/VolGroup00/lv-test vda
3. stop the VM and start it again.
  
Actual results:
Error starting domain: internal error unsupported driver name 'phy' for disk '/dev/VolGroup00/lv-test'

Expected results:
The VM can be started normally after attaching disk with cli.

Additional info:
It works fine to add disk with virt-manager

--- Additional comment from dwu on 2010-06-30 05:29:02 EDT ---

The xml sections for the new attached disk with CLI and GUI are different.
Generated by GUI
<disk type="block" device="disk">
  <source dev="/dev/disk1/Disk1"/>
  <target dev="vda" bus="virtio"/>
</disk>

Generated by CLI
<disk type="block" device="disk">
  <driver name="phy"/>
  <source dev="/dev/disk1/Disk1"/>
  <target dev="vda" bus="virtio"/>
</disk>

Virsh use phy as the default driver name if no driver specified in command line.
<snip>
    if (driver) {
        tmp = vshRealloc(ctl, tmp, strlen(driver) + 22);
        if (!tmp) goto cleanup;
        sprintf(tmp, "      <driver name='%s'", driver);
    } else {
        tmp = vshRealloc(ctl, tmp, 25);
        if (!tmp) goto cleanup;
        sprintf(tmp, "      <driver name='phy'");
    }
</snip>

But when the function qemudBuildCommandLine in qemu_conf.c try to parse the config and build a command line for qemu, it only can recognize "qemu" as a driver name.
<snip>
    if (disk->driverName != NULL &&
            !STREQ(disk->driverName, "qemu")) {
            qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
                             _("unsupported driver name '%s' for disk '%s'"),
                             disk->driverName, disk->src);
            goto error;
        }
</snip>

And for virsh, only file,tap and phy are valid, we can't specify "qemu" as a driver name in the command line.  The upstream code also has this problem.


This is fixed upstream by 12a41822e14b558f7ffb4812978b957f3d228f23 and dfec22cc6035a95ff1c7609ea060029cb99182cc