I plugged in a USB 2.0 external hard disk (ION) and the usb controller apparently could not power the device (wouldn't spin up, the device itself works on other machines). I unplug the drive and I received an OOPS.
DMESG: usb 4-5: new high speed USB device using ehci_hcd and address 6 scsi5 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 6 usb-storage: waiting for device to settle before scanning scsi: Device offlined - not ready after error recovery: host 5 channel 0 id 0 lun 0 usb 4-5: USB disconnect, address 6 usb-storage: device scan complete Unable to handle kernel NULL pointer dereference at virtual address 00000050 printing eip: c018cdef *pde = 00000000 Oops: 0000 [#1] PREEMPT SMP Modules linked in: nls_utf8 hfsplus nls_base mga drm nfsd exportfs tun ipv6 nfs lockd sunrpc parport_pc parport 8250_pnp sg sr_mod cdrom snd_ens1370 snd_rawmidi snd_seq_device snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc snd_ak4531_codec snd soundcore usb_storage ehci_hcd tsdev ohci_hcd usbhid i2c_piix4 i2c_core uhci_hcd usbcore piix ide_core intel_agp agpgart typhoon crc32 bridge reiserfs dm_mod 8250 serial_core CPU: 0 EIP: 0060:[<c018cdef>] Not tainted VLI EFLAGS: 00010282 (2.6.12) eax: 00000000 ebx: c02c2603 ecx: 0000001f edx: 00000000 esi: cbe1264c edi: c02fe7b0 ebp: c02fe740 esp: de84ade0 ds: 007b es: 007b ss: 0068 Process khubd (pid: 1057, threadinfo=de84a000 task=dfdf4590) Stack: 00000202 00000202 cbe12400 cbe12654 cbe1264c c02fe7b0 c02fe740 c0206808 00000000 c02c2603 cbe1264c cbe12598 d0b22800 db0f00e0 c0206833 cbe1264c cbe12400 c02217f8 cbe1264c 00000003 cbe12400 d0b22800 d0b227f8 c02218fb Call Trace: [<c0206808>] [<c0206833>] [<c02217f8>] [<c02218fb>] [<c02207e5>] [<c0219339>] [<e0c7aba3>] [<e0c19136>] [<c0205208>] [<c02054bb>] [<c0204269>] [<e0c20a50>] [<e0c1b6e6>] [<e0c1cb9f>] [<e0c1bac9>] [<e0c1ce68>] [<e0c1cfd5>] [<c0131520>] [<c0103272>] [<c0131520>] [<e0c1cfa0>] [<c010148d>] Code: 5c 24 08 8b 74 24 0c 8b 7c 24 10 83 c4 14 c3 8d b6 00 00 00 00 8d bc 27 00 00 00 00 55 57 56 53 83 ec 0c 8b 44 24 20 8b 5c 24 24 <8b> 48 50 8b 50 10 f0 ff 4a 78 0f 88 e3 00 00 00 8b 51 0c 8d 6a I guess I don't have symbols turned on, so here's the same thing from syslog: Jul 6 13:47:01 ani kernel: usb 4-5: new high speed USB device using ehci_hcd and address 6 Jul 6 13:47:01 ani kernel: scsi5 : SCSI emulation for USB Mass Storage devices Jul 6 13:47:01 ani kernel: usb-storage: device found at 6 Jul 6 13:47:01 ani kernel: usb-storage: waiting for device to settle before scanning Jul 6 13:47:30 ani kernel: scsi: Device offlined - not ready after error recovery: host 5 channel 0 id 0 lun 0 Jul 6 13:47:30 ani kernel: usb 4-5: USB disconnect, address 6 Jul 6 13:47:30 ani kernel: usb-storage: device scan complete Jul 6 13:47:30 ani kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000050 Jul 6 13:47:30 ani kernel: printing eip: Jul 6 13:47:30 ani kernel: c018cdef Jul 6 13:47:30 ani kernel: *pde = 00000000 Jul 6 13:47:30 ani kernel: Oops: 0000 [#1] Jul 6 13:47:30 ani kernel: PREEMPT SMP Jul 6 13:47:30 ani kernel: Modules linked in: nls_utf8 hfsplus nls_base mga drm nfsd exportfs tun ipv6 nfs lockd sunrpc parport_pc parport 8250_pnp sg sr_mod cdrom snd_ens1370 snd_rawmidi snd_seq_device snd_pcm_oss snd_mixer_oss snd_pcm snd_timer snd_page_alloc snd_ak4531_codec snd soundcore usb_storage ehci_hcd tsdev ohci_hcd usbhid i2c_piix4 i2c_core uhci_hcd usbcore piix ide_core intel_agp agpgart typhoon crc32 bridge reiserfs dm_mod 8250 serial_core Jul 6 13:47:30 ani kernel: CPU: 0 Jul 6 13:47:30 ani kernel: EIP: 0060:[sysfs_hash_and_remove+15/258] Not tainted VLI Jul 6 13:47:30 ani kernel: EFLAGS: 00010282 (2.6.12) Jul 6 13:47:30 ani kernel: eax: 00000000 ebx: c02c2603 ecx: 0000001f edx: 00000000 Jul 6 13:47:30 ani kernel: esi: cbe1264c edi: c02fe7b0 ebp: c02fe740 esp: de84ade0 Jul 6 13:47:30 ani kernel: ds: 007b es: 007b ss: 0068 Jul 6 13:47:30 ani kernel: Process khubd (pid: 1057, threadinfo=de84a000 task=dfdf4590) Jul 6 13:47:30 ani kernel: Stack: 00000202 00000202 cbe12400 cbe12654 cbe1264c c02fe7b0 c02fe740 c0206808 Jul 6 13:47:30 ani kernel: 00000000 c02c2603 cbe1264c cbe12598 d0b22800 db0f00e0 c0206833 cbe1264c Jul 6 13:47:30 ani kernel: cbe12400 c02217f8 cbe1264c 00000003 cbe12400 d0b22800 d0b227f8 c02218fb Jul 6 13:47:30 ani kernel: Call Trace: Jul 6 13:47:30 ani kernel: [class_device_del+184/208] Jul 6 13:47:30 ani kernel: [class_device_unregister+19/48] Jul 6 13:47:30 ani kernel: [scsi_remove_device+72/176] Jul 6 13:47:30 ani kernel: [__scsi_remove_target+155/192] Jul 6 13:47:30 ani kernel: [scsi_forget_host+69/112] Jul 6 13:47:30 ani kernel: [scsi_remove_host+25/128] Jul 6 13:47:30 ani kernel: [pg0+546339747/1070117888] Jul 6 13:47:30 ani kernel: [pg0+545939766/1070117888] Jul 6 13:47:30 ani kernel: [device_release_driver+120/128] Jul 6 13:47:30 ani kernel: [bus_remove_device+123/192] Jul 6 13:47:30 ani kernel: [device_del+89/160] Jul 6 13:47:30 ani kernel: [pg0+545970768/1070117888] Jul 6 13:47:30 ani kernel: [pg0+545949414/1070117888] Jul 6 13:47:30 ani kernel: [pg0+545954719/1070117888] Jul 6 13:47:30 ani kernel: [pg0+545950409/1070117888] Jul 6 13:47:30 ani kernel: [pg0+545955432/1070117888] Jul 6 13:47:30 ani kernel: [pg0+545955797/1070117888] Jul 6 13:47:30 ani kernel: [autoremove_wake_function+0/96] Jul 6 13:47:30 ani kernel: [ret_from_fork+6/20] Jul 6 13:47:30 ani kernel: [autoremove_wake_function+0/96] Jul 6 13:47:30 ani kernel: [pg0+545955744/1070117888] Jul 6 13:47:30 ani kernel: [kernel_thread_helper+5/24] Jul 6 13:47:30 ani kernel: Code: 5c 24 08 8b 74 24 0c 8b 7c 24 10 83 c4 14 c3 8d b6 00 00 00 00 8d bc 27 00 00 00 00 55 57 56 53 83 ec 0c 8b 44 24 20 8b 5c 24 24 <8b> 48 50 8b 50 10 f0 ff 4a 78 0f 88 e3 00 00 00 8b 51 0c 8d 6a -- Lab tests show that use of micro$oft causes cancer in lab animals - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/