Bug 854113

Description of problem:
Boot a guest with a cdrom, such as cdimg.iso, and verify it  mount automatically in the guest, and then change the media for two times, it will be locked and fail to change again. I eject the media with "force" option in monitor, and it succeed，but then change the media two times, it also will be locked and fail to change again, the value of 'locked' will be changed to '1' after the second change, but why the value of 'locked' was '0' at the first time change.
BTW, there is a bug 676528 has been fixed with the issue that guest cdrom will always be locked after eject the media with 'force' option.

Version-Release number of selected component (if applicable):
host info:
# uname -r && rpm -q qemu-kvm
2.6.32-303.el6.x86_64
qemu-kvm-0.12.1.2-2.307.el6.x86_64
guest info:
# uname -r
2.6.32-303.el6.x86_64

How reproducible:
100%

Steps to Reproduce:
1.boot a guest with cdrom.
# /usr/libexec/qemu-kvm -M rhel6.3.0 -cpu SandyBridge -enable-kvm -m 2048 -smp 2,sockets=2,cores=1,threads=1 -usb -device usb-tablet,id=input0 -name virtio-scsi-pci -uuid `uuidgen` -device virtio-scsi-pci,bus=pci.0,addr=0x3,id=scsi0 -drive file=/home/RHEL-Server-6.3-64-sluo.qcow2,format=qcow2,if=none,id=drive-disk,cache=none,werror=stop,rerror=stop,aio=native -device scsi-hd,drive=drive-disk,bus=scsi0.0,scsi-id=0,lun=0,bootindex=2 -netdev tap,id=hostnet0,script=/etc/qemu-ifup -device virtio-net-pci,netdev=hostnet0,id=virtio-net-pci0,mac=98:3B:CB:2E:90:A8,bus=pci.0,addr=0x4 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 -serial unix:/tmp/ttyS1,server,nowait -vnc :2 -bios /usr/share/seabios/bios-pm.bin -qmp tcp:0:5555,server,nowait -boot menu=on -monitor stdio -drive file=/home/cdimg.iso,if=none,readonly=on,media=cdrom,id=drive-ide0-1-0,format=raw -device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0
2.wait the guest boot up and verify the filesystem was mounted automatically.
in monitor:
(qemu) info block
drive-disk: removable=0 io-status=ok file=/home/RHEL-Server-6.3-64-sluo.qcow2 ro=0 drv=qcow2 encrypted=0
drive-ide0-1-0: removable=1 locked=0 tray-open=0 io-status=ok file=/home/cdimg.iso ro=1 drv=raw encrypted=0
in guest:
# mount
...
(ro,nosuid,nodev,uhelper=udisks,uid=0,gid=0,iocharset=utf8,mode=0400,dmode=0500)
3.change the cdrom media for two time, verify the filesystem was mounted automatically every time.
(qemu) info block
drive-disk: removable=0 io-status=ok file=/home/RHEL-Server-6.3-64-sluo.qcow2 ro=0 drv=qcow2 encrypted=0
drive-ide0-1-0: removable=1 locked=0 tray-open=0 io-status=ok file=/home/cdimg.iso ro=1 drv=raw encrypted=0
...
(qemu) change drive-ide0-1-0 /home/en_win_srv_2003_r2_enterprise_x64_with_sp2_X13.iso
(qemu) info block
drive-disk: removable=0 io-status=ok file=/home/RHEL-Server-6.3-64-sluo.qcow2 ro=0 drv=qcow2 encrypted=0
drive-ide0-1-0: removable=1 locked=0 tray-open=0 io-status=ok file=/home/en_win_srv_2003_r2_enterprise_x64_with_sp2_X13.iso ro=1 drv=raw encrypted=0
...
(qemu) change drive-ide0-1-0 /home/cdimg.iso 
(qemu) info block
drive-disk: removable=0 io-status=ok file=/home/RHEL-Server-6.3-64-sluo.qcow2 ro=0 drv=qcow2 encrypted=0
drive-ide0-1-0: removable=1 locked=1 tray-open=0 io-status=ok file=/home/cdimg.iso ro=1 drv=raw encrypted=0
...
(qemu) change drive-ide0-1-0 /home/cdimg.iso 
Device 'drive-ide0-1-0' is locked
4.eject the cdrom by force and change it for two time, verify the filesystem was mounted automatically every time.
(qemu) eject -f drive-ide0-1-0
(qemu) info block
drive-disk: removable=0 io-status=ok file=/home/RHEL-Server-6.3-64-sluo.qcow2 ro=0 drv=qcow2 encrypted=0
...
(qemu) change drive-ide0-1-0 /home/cdimg.iso 
(qemu) info block
drive-disk: removable=0 io-status=ok file=/home/RHEL-Server-6.3-64-sluo.qcow2 ro=0 drv=qcow2 encrypted=0
drive-ide0-1-0: removable=1 locked=0 tray-open=0 io-status=ok file=/home/cdimg.iso ro=1 drv=raw encrypted=0
...
(qemu) change drive-ide0-1-0 /home/en_win_srv_2003_r2_enterprise_x64_with_sp2_X13.iso
(qemu) info block
drive-disk: removable=0 io-status=ok file=/home/RHEL-Server-6.3-64-sluo.qcow2 ro=0 drv=qcow2 encrypted=0
drive-ide0-1-0: removable=1 locked=1 tray-open=0 io-status=ok file=/home/en_win_srv_2003_r2_enterprise_x64_with_sp2_X13.iso ro=1 drv=raw encrypted=0
...
(qemu) change drive-ide0-1-0 /home/cdimg.iso 
Device 'drive-ide0-1-0' is locked

Actual results:
in the step 3/4, the cdrom media was locked and fail to change it again after the second time change the media.

Expected results:
can change the cdrom media freely and successfully without any problem.

Additional info: