Comment 4 for bug 221677

I can confirm this bug:

After upgrading to 8.04, the kernel doesn't recognize one of my hard disks (the one with the root partition on it) any more (a seagate IDE disk). Booting with the old (2.6.22) kernel works fine. It's not recognized by the live CD either. The other disk (also IDE) is displayed alright, all partitions show up correctly in /dev/disk/* as sdd* as expected. The disk without the partition table _does_ show up as a block device as /dev/sdc, though.

Relevant output from lshw (run under 2.6.22) follows:

           *-ide:1
                description: IDE Channel 1
                physical id: 1
                bus info: ide@1
                logical name: ide1
                clock: 33MHz
              *-disk:0
                   description: ATA Disk
                   product: ST3160812A
                   vendor: Seagate
                   physical id: 0
                   bus info: ide@1.0
                   logical name: /dev/hdc
                   version: 3.AAJ
                   serial: 4LS440SN
                   size: 149GiB (160GB)
                   capabilities: ata dma lba iordy smart security pm partitioned partitioned:dos
                   configuration: mode=udma2 signature=bbbbbbbb smart=on
                 *-volume:0
                      description: EXT3 volume
                      vendor: Linux
                      physical id: 1
                      bus info: ide@1.0,1
                      logical name: /dev/hdc1
                      logical name: /
                      logical name: /dev/.static/dev
                      version: 1.0
                      serial: 9bdd3a49-2483-4c2d-9b4a-6aaf1e089a73
                      size: 20GiB
                      capacity: 20GiB
                      capabilities: primary bootable journaled extended_attributes large_files huge_files recover ext3 ext2 initialized
                      configuration: created=2008-02-06 19:02:16 filesystem=ext3 modified=2008-04-26 23:25:04 mount.fstype=ext3 mount.options=rw,data=ordered mounted=2008-04-26 23:25:04 state=mounted
                 *-volume:1
                      description: Linux swap volume
                      physical id: 2
                      bus info: ide@1.0,2
                      logical name: /dev/hdc2
                      version: 1
                      serial: 1b77acd9-bea4-47fd-b12b-c2bbb12f327d
                      size: 972MiB
                      capacity: 972MiB
                      capabilities: primary nofs swap initialized
                      configuration: filesystem=swap pagesize=4096
                 *-volume:2
                      description: EXT3 volume
                      vendor: Linux
                      physical id: 3
                      bus info: ide@1.0,3
                      logical name: /dev/hdc3
                      logical name: /home
                      version: 1.0
                      serial: bd9da549-79e8-46fb-b08a-8036ae1c11f6
                      size: 29GiB
                      capacity: 29GiB
                      capabilities: primary journaled extended_attributes large_files huge_files recover ext3 ext2 initialized
                      configuration: created=2008-02-06 19:02:40 filesystem=ext3 modified=2008-04-26 23:26:23 mount.fstype=ext3 mount.options=rw,data=ordered mounted=2008-04-26 23:26:23 state=mounted
                 *-volume:3
                      description: Windows FAT volume
                      vendor: mkdosfs
                      physical id: 4
                      bus info: ide@1.0,4
                      logical name: /dev/hdc4
                      logical name: /data-neu
                      version: FAT32
                      serial: 47a9-fbc4
                      size: 98GiB
                      capacity: 98GiB
                      capabilities: primary fat initialized
                      configuration: FATs=2 filesystem=fat label=dataneu mount.fstype=vfat mount.options=rw,gid=46,fmask=0007,dmask=0007,codepage=cp437,iocharset=iso8859-1,utf8 state=mounted
              *-disk:1
                   description: ATA Disk
                   product: IBM-DTLA-307030
                   vendor: IBM
                   physical id: 1
                   bus info: ide@1.1
                   logical name: /dev/hdd
                   version: TX4OA50C
                   serial: YK0YKT2P876
                   size: 28GiB (30GB)
                   capacity: 28GiB (30GB)
                   capabilities: ata dma lba iordy smart security pm apm partitioned partitioned:dos
                   configuration: apm=off mode=udma2 signature=0a6b0a6a smart=on
                 *-volume:0
                      description: Windows FAT volume
                      vendor: MSDOS5.0
                      physical id: 1
                      bus info: ide@1.1,1
                      logical name: /dev/hdd1
                      logical name: /windows
                      version: FAT32
                      serial: 688d-c6c1
                      size: 10001MiB
                      capacity: 10001MiB
                      capabilities: primary bootable fat initialized
                      configuration: FATs=2 filesystem=fat mount.fstype=vfat mount.options=rw,gid=46,fmask=0007,dmask=0007,codepage=cp437,iocharset=iso8859-1,utf8 state=mounted
                 *-volume:1
                      description: Linux swap volume
                      physical id: 2
                      bus info: ide@1.1,2
                      logical name: /dev/hdd2
                      version: 1
                      serial: 0c94c6f1-d36f-42d4-bb79-5c4a04966d12
                      size: 368MiB
                      capacity: 368MiB
                      capabilities: primary nofs swap initialized
                      configuration: filesystem=swap pagesize=4096
                 *-volume:2
                      description: Windows FAT volume
                      vendor: mkdosfs
                      physical id: 3
                      bus info: ide@1.1,3
                      logical name: /dev/hdd3
                      logical name: /data-alt
                      version: FAT32
                      serial: 46df-3e0f
                      size: 18GiB
                      capacity: 18GiB
                      capabilities: primary fat initialized
                      configuration: FATs=2 filesystem=fat mount.fstype=vfat mount.options=rw,gid=46,fmask=0007,dmask=0007,codepage=cp437,iocharset=iso8859-1,utf8 state=mounted

Please pass this bug over to the kernel team as critical (unable to mount the root file system here), and possibly also upstream. (Don't know if this is fixed in a newer kernel version maybe.)