I am forwarding this bug from https://bugs.launchpad.net/ubuntu/+bug/761723

The original reporter has the following hardware"

GraphicsCard:
 ATI Technologies Inc Mobility Radeon HD 3650 [1002:9591] (prog-if 00 [VGA controller])
   Subsystem: Toshiba America Info Systems Device [1179:ff62]
LiveMediaBuild: Ubuntu 11.04 "Natty Narwhal" - Beta amd64 (20110413)
MachineType: TOSHIBA Satellite A300D

The original bug description is:

After upgrading from Maverick to Natty, this machine (now running via a Live CD) becomes unbootable. The boot process seems to start off OK, but then finishes with an "aubergine screen of death" with a solid blue line at the top (see attached photo). I have tried the upgrade via both apt and the live CD but the two methods fail in the same way. Trying to boot via the fail safe mode also results in a system freeze (black screen of death this time!)

Also:

Tried again this morning, with the newly released final released. I was very disappointed to see that the problem remains. I wonder how many first time Linux users will have this as their very first Ubuntu experience.

Another user reports what they believe to be the same problem, saying "This also impacts me. Here's the relevant part of dmesg:"

Apr 26 16:24:38 jm-t500 avahi-dnsconfd[1147]: Successfully connected to Avahi daemon.
Apr 26 16:24:39 jm-t500 kernel: [ 18.789976] BUG: unable to handle kernel NULL pointer dereference at 0000008e
Apr 26 16:24:39 jm-t500 kernel: [ 18.790015] IP: [<f85cf7be>] drm_mode_connector_update_edid_property+0x5e/0x170 [drm]
Apr 26 16:24:39 jm-t500 kernel: [ 18.790065] *pdpt = 0000000030d60001 *pde = 0000000000000000
Apr 26 16:24:39 jm-t500 kernel: [ 18.790092] Oops: 0000 [#1] SMP
Apr 26 16:24:39 jm-t500 kernel: [ 18.790111] last sysfs file: /sys/module/bluetooth/initstate
Apr 26 16:24:39 jm-t500 kernel: [ 18.790140] Modules linked in: bnep snd_hda_codec_conexant l2cap snd_hda_intel snd_hda_codec snd_hwdep snd_pcm thinkpad_acpi snd_seq_midi snd_rawmidi arc4 snd_seq_midi_event snd_seq snd_timer joydev pcmcia yenta_socket r852 sm_common nand nand_ids snd_seq_device iwlagn pcmcia_rsrc radeon(+) snd lp btusb iwlcore ttm mac80211 nand_ecc mtd psmouse uvcvideo videodev hid_apple pcmcia_core soundcore cfg80211 tpm_tis tpm tpm_bios nvram serio_raw usbhid hid snd_page_alloc bluetooth parport i915 firewire_ohci firewire_core sdhci_pci drm_kms_helper drm ahci sdhci crc_itu_t e1000e libahci i2c_algo_bit video
Apr 26 16:24:39 jm-t500 kernel: [ 18.790457]
Apr 26 16:24:39 jm-t500 kernel: [ 18.790467] Pid: 551, comm: modprobe Not tainted 2.6.38-8-generic-pae #42-Ubuntu LENOVO 20553AU/20553AU
Apr 26 16:24:39 jm-t500 kernel: [ 18.790517] EIP: 0060:[<f85cf7be>] EFLAGS: 00010202 CPU: 0
Apr 26 16:24:39 jm-t500 kernel: [ 18.790553] EIP is at drm_mode_connector_update_edid_property+0x5e/0x170 [drm]
Apr 26 16:24:39 jm-t500 kernel: [ 18.790589] EAX: 00000010 EBX: f604c000 ECX: f0c78000 EDX: 000080d0
Apr 26 16:24:39 jm-t500 kernel: [ 18.790616] ESI: 00000000 EDI: 00000010 EBP: f0cc5c94 ESP: f0cc5c7c
Apr 26 16:24:39 jm-t500 kernel: [ 18.790643] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Apr 26 16:24:39 jm-t500 kernel: [ 18.790668] Process modprobe (pid: 551, ti=f0cc4000 task=f0c4e500 task.ti=f0cc4000)
Apr 26 16:24:39 jm-t500 kernel: [ 18.790700] Stack:
Apr 26 16:24:39 jm-t500 kernel: [ 18.790712] f0911000 f0c78000 00000010 f604c000 f0911000 f604c170 f0cc5ca4 f996ba9d
Apr 26 16:24:39 jm-t500 kernel: [ 18.790754] f604c000 00002000 f0cc5cd8 f99652f4 f0cc5cc8 f9964e8b 00000001 f0c18c00
Apr 26 16:24:39 jm-t500 kernel: [ 18.790797] 00000001 f604c000 f604c170 f604c000 f604c000 00002000 f604c170 f0cc5d14
Apr 26 16:24:39 jm-t500 kernel: [ 18.790839] Call Trace:
Apr 26 16:24:39 jm-t500 kernel: [ 18.790876] [<f996ba9d>] radeon_ddc_get_modes+0x4d/0xf0 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.790920] [<f99652f4>] radeon_lvds_get_modes+0x24/0x280 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.790964] [<f9964e8b>] ? radeon_connector_update_scratch_regs+0x6b/0x90 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791005] [<f8584cd6>] drm_helper_probe_single_connector_modes+0xc6/0x340 [drm_kms_helper]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791051] [<f85842f3>] drm_fb_helper_initial_config+0xb3/0xf0 [drm_kms_helper]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791101] [<f9972f58>] radeon_fbdev_init+0x98/0x110 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791146] [<f996c949>] radeon_modeset_init+0x1f9/0x220 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791193] [<f9947e9e>] radeon_driver_load_kms+0xee/0x160 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791236] [<f85cb884>] drm_get_pci_dev+0x144/0x2b0 [drm]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791268] [<c1035908>] ? default_spin_lock_flags+0x8/0x10
Apr 26 16:24:39 jm-t500 kernel: [ 18.791311] [<f99d55cb>] ? radeon_pci_probe+0x2f/0xc7 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791353] [<f99d55cb>] ? radeon_pci_probe+0x2f/0xc7 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791395] [<f99d565c>] radeon_pci_probe+0xc0/0xc7 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791423] [<c129efe7>] local_pci_probe+0x47/0xb0
Apr 26 16:24:39 jm-t500 kernel: [ 18.791447] [<c12a0468>] pci_device_probe+0x68/0x90
Apr 26 16:24:39 jm-t500 kernel: [ 18.791474] [<c134d43d>] really_probe+0x4d/0x150
Apr 26 16:24:39 jm-t500 kernel: [ 18.791497] [<c135562b>] ? pm_runtime_barrier+0x4b/0xb0
Apr 26 16:24:39 jm-t500 kernel: [ 18.791525] [<c134d6dc>] driver_probe_device+0x3c/0x60
Apr 26 16:24:39 jm-t500 kernel: [ 18.791549] [<c134d781>] __driver_attach+0x81/0x90
Apr 26 16:24:39 jm-t500 kernel: [ 18.791571] [<c134d700>] ? __driver_attach+0x0/0x90
Apr 26 16:24:39 jm-t500 kernel: [ 18.791598] [<c134c838>] bus_for_each_dev+0x48/0x70
Apr 26 16:24:39 jm-t500 kernel: [ 18.791624] [<c129fe70>] ? pci_device_remove+0x0/0xf0
Apr 26 16:24:39 jm-t500 kernel: [ 18.791649] [<c134d2ee>] driver_attach+0x1e/0x20
Apr 26 16:24:39 jm-t500 kernel: [ 18.791670] [<c134d700>] ? __driver_attach+0x0/0x90
Apr 26 16:24:39 jm-t500 kernel: [ 18.791696] [<c134cf08>] bus_add_driver+0xb8/0x250
Apr 26 16:24:39 jm-t500 kernel: [ 18.791720] [<c129fe70>] ? pci_device_remove+0x0/0xf0
Apr 26 16:24:39 jm-t500 kernel: [ 18.791746] [<c134d9c6>] driver_register+0x66/0x110
Apr 26 16:24:39 jm-t500 kernel: [ 18.791772] [<c129f585>] __pci_register_driver+0x45/0xb0
Apr 26 16:24:39 jm-t500 kernel: [ 18.791806] [<f85cbcd6>] drm_pci_init+0x96/0xc0 [drm]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791841] [<f85c4124>] drm_init+0x54/0x70 [drm]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791882] [<f9a110b7>] radeon_init+0xb7/0x1000 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791913] [<c1003165>] do_one_initcall+0x35/0x170
Apr 26 16:24:39 jm-t500 kernel: [ 18.791949] [<f9a11000>] ? radeon_init+0x0/0x1000 [radeon]
Apr 26 16:24:39 jm-t500 kernel: [ 18.791977] [<c10922db>] sys_init_module+0xdb/0x230
Apr 26 16:24:39 jm-t500 kernel: [ 18.792003] [<c100ab5f>] sysenter_do_call+0x12/0x28
Apr 26 16:24:39 jm-t500 kernel: [ 18.792004] Code: 10 89 f0 c7 46 08 00 01 10 00 c7 46 0c 00 02 20 00 e8 c7 63 b5 c8 8b 7d f0 85 ff 0f 84 c4 00 00 00 8b 45 f0 ba d0 80 00 00 8b 0b <0f> b6 78 7e 89 4d e8 83 c7 01 c1 e7 07 8d 47 18 e8 6d 6a b5 c8
Apr 26 16:24:39 jm-t500 kernel: [ 18.792004] EIP: [<f85cf7be>] drm_mode_connector_update_edid_property+0x5e/0x170 [drm] SS:ESP 0068:f0cc5c7c
Apr 26 16:24:39 jm-t500 kernel: [ 18.792004] CR2: 000000000000008e
Apr 26 16:24:39 jm-t500 udevd-work[487]: '/sbin/modprobe -bv pci:v00001002d00009591sv000017AAsd00002116bc03sc00i00' unexpected exit with status 0x0009
Apr 26 16:24:39 jm-t500 kernel: [ 18.813581] ---[ end trace 256f52b10f0172f2 ]---

This is a Thinkpad t500 with a Radeon HD 3650

uname -a: Linux jm-t500 2.6.38-8-generic-pae #42-Ubuntu SMP Mon Apr 11 05:17:09 UTC 2011 i686 i686 i386 GNU/Linux

lspci -vnn | grep VGA:

00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07) (prog-if 00 [VGA controller])
01:00.0 VGA compatible controller [0300]: ATI Technologies Inc Mobility Radeon HD 3650 [1002:9591] (prog-if 00 [VGA controller])

I have attached the original reporter's screenshot.  Their dmesg and XorgLog can be found at the original report linked above.