Happens as well in 2.6.20-[45]-{generic,lowlatency}. This bug doesn't seem to crash the system for me; it just spews messy bugs into dmesg and makes Xorg not want to load (I'm using the Via driver). I removed linux-restricted-modules for the kernel I'm using to get rid of the driver after trying to reboot like 10 times. My syslog segment for this is below. Jan 14 12:49:20 localhost kernel: [ 58.364501] ath_rate_sample: 1.2 (0.9.2.1) Jan 14 12:49:20 localhost kernel: [ 58.382930] ath_pci: 0.9.4.5 (0.9.2.1) Jan 14 12:49:20 localhost kernel: [ 58.382992] ACPI: PCI Interrupt 0000:00:0b.0[A] -> GSI 19 (level, low) -> IRQ 19 Jan 14 12:49:20 localhost kernel: [ 58.383036] wifi%%d: unable to attach hardware: '' (HAL status 4172484335) Jan 14 12:49:20 localhost kernel: [ 58.383056] ACPI: PCI interrupt for device 0000:00:0b.0 disabled Jan 14 12:49:20 localhost kernel: [ 58.434478] sr0: scsi3-mmc drive: 1x/48x writer cd/rw xa/form2 cdda tray Jan 14 12:49:20 localhost kernel: [ 58.434486] Uniform CD-ROM driver Revision: 3.20 Jan 14 12:49:20 localhost kernel: [ 58.435892] sr 3:0:0:0: Attached scsi CD-ROM sr0 Jan 14 12:49:20 localhost kernel: [ 58.694974] ACPI: PCI Interrupt 0000:00:09.0[A] -> GSI 17 (level, low) -> IRQ 20 Jan 14 12:49:20 localhost kernel: [ 58.861941] ACPI: PCI Interrupt Link [ALKC] BIOS reported IRQ 0, using IRQ 22 Jan 14 12:49:20 localhost kernel: [ 58.861948] ACPI: PCI Interrupt Link [ALKC] enabled at IRQ 22 Jan 14 12:49:20 localhost kernel: [ 58.861957] ACPI: PCI Interrupt 0000:00:11.5[C] -> Link [ALKC] -> GSI 22 (level, low) -> IRQ 21 Jan 14 12:49:20 localhost kernel: [ 58.862103] BUG: unable to handle kernel NULL pointer dereference at virtual address 00000025 Jan 14 12:49:20 localhost kernel: [ 58.862106] printing eip: Jan 14 12:49:20 localhost kernel: [ 58.862108] c01fa52f Jan 14 12:49:20 localhost kernel: [ 58.862109] *pde = 00000000 Jan 14 12:49:20 localhost kernel: [ 58.862113] Oops: 0000 [#1] Jan 14 12:49:20 localhost kernel: [ 58.862114] PREEMPT SMP Jan 14 12:49:20 localhost kernel: [ 58.862117] Modules linked in: snd_via82xx gameport snd_mpu401_uart snd_seq_dummy snd_seq_oss snd_emu10k1 snd_ac97_codec ac97_bus snd_pcm_oss snd_mixer_oss snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_pcm snd_seq_device snd_timer snd_page_alloc snd_util_mem sr_mod cdrom k8temp ath_pci ath_rate_sample snd_hwdep amd64_agp snd psmouse i2c_viapro serio_raw i2c_core wlan shpchp pci_hotplug pcspkr 8139cp soundcore agpgart generic ath_hal(P) evdev ipv6 ata_generic ext3 jbd mbcache sg sd_mod 8139too mii ehci_hcd uhci_hcd usbcore pata_via sata_via libata scsi_mod ohci1394 ieee1394 raid10 raid456 xor raid1 raid0 multipath linear md_mod thermal processor fan fbcon tileblit font bitblit softcursor vesafb capability commoncap Jan 14 12:49:20 localhost kernel: [ 58.862168] CPU: 0 Jan 14 12:49:20 localhost kernel: [ 58.862169] EIP: 0060:[pci_get_subsys+79/240] Tainted: P VLI Jan 14 12:49:20 localhost kernel: [ 58.862170] EFLAGS: 00010213 (2.6.20-4-lowlatency #2) Jan 14 12:49:20 localhost kernel: [ 58.862179] EIP is at pci_get_subsys+0x4f/0xf0 Jan 14 12:49:20 localhost kernel: [ 58.862182] eax: 0000168c ebx: 00001106 ecx: 00000001 edx: 00000001 Jan 14 12:49:20 localhost kernel: [ 58.862186] esi: 00003068 edi: ffffffff ebp: 00000000 esp: f7d91d40 Jan 14 12:49:20 localhost kernel: [ 58.862188] ds: 007b es: 007b ss: 0068 Jan 14 12:49:20 localhost kernel: [ 58.862191] Process modprobe (pid: 5578, ti=f7d90000 task=f7c47570 task.ti=f7d90000) Jan 14 12:49:20 localhost kernel: [ 58.862194] Stack: 00000213 c02ec665 c01f49c3 00000001 fffbf940 f4c89400 f7d91d83 f4c89400 Jan 14 12:49:20 localhost kernel: [ 58.862201] c01fa5e8 ffffffff 00000000 f8cac3c2 f7d91d83 00000080 f8cad100 c0152543 Jan 14 12:49:20 localhost kernel: [ 58.862207] 01586480 00000000 00000000 df832000 f4c89400 f8cad58b f69d7e14 f4c89400 Jan 14 12:49:20 localhost kernel: [ 58.862213] Call Trace: Jan 14 12:49:20 localhost kernel: [ 58.862220] [_spin_unlock_irqrestore+21/48] _spin_unlock_irqrestore+0x15/0x30 Jan 14 12:49:20 localhost kernel: [ 58.862226] [pci_bus_read_config_byte+99/128] pci_bus_read_config_byte+0x63/0x80 Jan 14 12:49:20 localhost kernel: [ 58.862243] [pci_get_device+24/32] pci_get_device+0x18/0x20 Jan 14 12:49:20 localhost kernel: [ 58.862253] [pg0+948106178/1069028352] snd_via82xx_chip_init+0xe2/0x250 [snd_via82xx] Jan 14 12:49:20 localhost kernel: [ 58.862266] [pg0+948109568/1069028352] snd_via8233_interrupt+0x0/0xf0 [snd_via82xx] Jan 14 12:49:20 localhost kernel: [ 58.862272] [request_irq+163/192] request_irq+0xa3/0xc0 Jan 14 12:49:20 localhost kernel: [ 58.862291] [pg0+948110731/1069028352] snd_via82xx_probe+0x24b/0x1030 [snd_via82xx] Jan 14 12:49:20 localhost kernel: [ 58.862349] [sysfs_make_dirent+28/144] sysfs_make_dirent+0x1c/0x90 Jan 14 12:49:20 localhost kernel: [ 58.862357] [sysfs_dirent_exist+69/112] sysfs_dirent_exist+0x45/0x70 Jan 14 12:49:20 localhost kernel: [ 58.862374] [sysfs_create_link+110/352] sysfs_create_link+0x6e/0x160 Jan 14 12:49:20 localhost kernel: [ 58.862386] [_spin_unlock+17/48] _spin_unlock+0x11/0x30 Jan 14 12:49:20 localhost kernel: [ 58.862390] [store_new_id+146/384] store_new_id+0x92/0x180 Jan 14 12:49:20 localhost kernel: [ 58.862397] [pg0+948110144/1069028352] snd_via82xx_probe+0x0/0x1030 [snd_via82xx] Jan 14 12:49:20 localhost kernel: [ 58.862411] [pci_device_probe+86/128] pci_device_probe+0x56/0x80 Jan 14 12:49:20 localhost kernel: [ 58.862424] [really_probe+84/320] really_probe+0x54/0x140 Jan 14 12:49:20 localhost kernel: [ 58.862433] [driver_probe_device+73/192] driver_probe_device+0x49/0xc0 Jan 14 12:49:20 localhost kernel: [ 58.862437] [_spin_unlock+17/48] _spin_unlock+0x11/0x30 Jan 14 12:49:20 localhost kernel: [ 58.862441] [klist_next+93/160] klist_next+0x5d/0xa0 Jan 14 12:49:20 localhost kernel: [ 58.862458] [__driver_attach+128/144] __driver_attach+0x80/0x90 Jan 14 12:49:20 localhost kernel: [ 58.862466] [bus_for_each_dev+59/96] bus_for_each_dev+0x3b/0x60 Jan 14 12:49:20 localhost kernel: [ 58.862490] [driver_attach+22/32] driver_attach+0x16/0x20 Jan 14 12:49:20 localhost kernel: [ 58.862494] [__driver_attach+0/144] __driver_attach+0x0/0x90 Jan 14 12:49:20 localhost kernel: [ 58.862498] [bus_add_driver+123/416] bus_add_driver+0x7b/0x1a0 Jan 14 12:49:20 localhost kernel: [ 58.862525] [__pci_register_driver+126/192] __pci_register_driver+0x7e/0xc0 Jan 14 12:49:20 localhost kernel: [ 58.862537] [sys_init_module+349/7152] sys_init_module+0x15d/0x1bf0 Jan 14 12:49:20 localhost kernel: [ 58.862678] [sys_mmap2+205/208] sys_mmap2+0xcd/0xd0 Jan 14 12:49:20 localhost kernel: [ 58.862705] [sysenter_past_esp+95/137] sysenter_past_esp+0x5f/0x89 Jan 14 12:49:20 localhost kernel: [ 58.862757] ======================= Jan 14 12:49:20 localhost kernel: [ 58.862759] Code: 00 b8 e4 7e 3a c0 e8 d1 20 f4 ff 85 ed 0f 84 7b 00 00 00 8b 55 00 85 d2 74 1f 66 90 81 fa a8 7a 3a c0 74 15 83 fb ff 89 d1 74 34 <0f> b7 42 24 39 c3 74 2c 8b 12 85 d2 75 e3 31 c9 89 c8 e8 ba f6 Jan 14 12:49:20 localhost kernel: [ 58.862788] EIP: [pci_get_subsys+79/240] pci_get_subsys+0x4f/0xf0 SS:ESP 0068:f7d91d40