kernel BUG at /build/buildd/linux-2.6.32/drivers/gpu/drm/drm_fops.c:146!

------------[ cut here ]------------
kernel BUG at /build/buildd/linux-2.6.32/drivers/gpu/drm/drm_fops.c:146!
invalid opcode: 0000 [#2] SMP
last sysfs file: /sys/devices/pci0000:00/0000:00:09.0/0000:02:00.0/boot_vga
CPU 0
Modules linked in: snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi fbcon tileblit font bitblit softcursor snd_seq_midi_event vga16fb snd_seq vgastate snd_timer snd_seq_device nouveau ppdev edac_core ttm snd drm_kms_helper parport_pc drm i2c_algo_bit i2c_nforce2 lp psmouse serio_raw edac_mce_amd soundcore snd_page_alloc k8temp parport dm_raid45 sata_nv forcedeth pata_amd xor
Pid: 1066, comm: Xorg Tainted: G D 2.6.32-19-generic #28-Ubuntu A15G
RIP: 0010:[<ffffffffa00b805f>] [<ffffffffa00b805f>] drm_open+0x10f/0x120 [drm]
RSP: 0018:ffff8800ba3b1c68 EFLAGS: 00010206
RAX: ffff8800bab0cb48 RBX: 0000000000000000 RCX: 0000000000000015
RDX: 0000000000000000 RSI: ffff8800bb1c7240 RDI: ffff8800baa90820
RBP: ffff8800ba3b1c98 R08: ffff880001c11fe0 R09: 00000000000000c0
R10: ffff8800bc3323c0 R11: 0000000000000002 R12: ffff8800ba384c00
R13: ffff8800baab6970 R14: ffff8800baa90800 R15: ffff8800baa90820
FS: 00007f2ab9298700(0000) GS:ffff880001c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2ab5bc4c80 CR3: 00000000b9c24000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process Xorg (pid: 1066, threadinfo ffff8800ba3b0000, task ffff8800baf02de0)
Stack:
 000000000e200000 ffffffffa00ca7e0 ffff8800baab6970 ffff8800bb1c7000
<0> 00000000ffffffed ffff8800baa90800 ffff8800ba3b1ce8 ffffffffa00b81a3
<0> ffff8800b9cc8380 ffff8800bc630000 0000000000000000 0000000000000000
Call Trace:
 [<ffffffffa00b81a3>] drm_stub_open+0x133/0x260 [drm]
 [<ffffffff8114650a>] chrdev_open+0x13a/0x240
 [<ffffffff811463d0>] ? chrdev_open+0x0/0x240
 [<ffffffff81140823>] __dentry_open+0x113/0x370
 [<ffffffff8125177f>] ? security_inode_permission+0x1f/0x30
 [<ffffffff8114cbaf>] ? inode_permission+0xaf/0xd0
 [<ffffffff81140b97>] nameidata_to_filp+0x57/0x70
 [<ffffffff81150dea>] do_filp_open+0x2da/0xba0
 [<ffffffff8115c89a>] ? alloc_fd+0x10a/0x150
 [<ffffffff81140599>] do_sys_open+0x69/0x170
 [<ffffffff811406e0>] sys_open+0x20/0x30
 [<ffffffff810131b2>] system_call_fastpath+0x16/0x1b
Code: 89 ff e8 15 17 f8 e0 66 90 eb 99 90 4c 89 ff e8 08 17 f8 e0 66 90 4c 89 f7 e8 ce f9 ff ff 89 c3 eb 82 49 3b 85 10 01 00 00 74 a7 <0f> 0b eb fe 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5
RIP [<ffffffffa00b805f>] drm_open+0x10f/0x120 [drm]
 RSP <ffff8800ba3b1c68>
---[ end trace 0ec7af0ebca54358 ]---

Which version of Ubuntu is the "existing installation"? Which version of Ubuntu worked correctly on this system, if any?

Existing installation is on sdb1, which I use on a daily basis. It is an installation of Lucid installed fresh. Xubuntu karmic worked, as did Xubuntu Alpha 2 and 3.

Charlie there have been some recent kernel updates and I was wondering if you are still affected by this bug report.

Yes, I would gladly try another installation if it helps. I reinstalled, using both the Xubuntu alternate image, dated 2010-04-16, and the Xubuntu Desktop image, dated 2010-04-17. Both images installed and ran! I think I can say this issue is fixed, whether or not we know what fixed it. I was able to perform the same installations and additions without the monitor shutting off and the system inaccessible. The two items I did find are:

Alternate installer insists drives are a raid array if they are partitioned the same, regardless of mount points and denial from user. My third drive has two 110 GiB partitions, which are identified as failing to properly mount as a raid array. They are simply two partitions, which I designated be mounted as /usr/bak/Downloads and /usr/bak/Music. They are not accessible after the install from the alternate cd because it doesn't find the array usable.

The Desktop image does not recognize three hard drives as valid. I could use sda or sdb, but not sdc. I can not even tell it to use the third hard drive, because it is not in the partition editor.

This appears to be fixed. I did all hardware installs for the pre-rc testing, and never saw this issue again. Thanks for the efforts.

Setting to Fix Released since the original reporter indicates that it is fixed. Please feel free to reopen this bug if you are experiencing the exact same issue.