I am also seeing this problem -- and additionally the main keyboard and mouse lock up -- plugging external usb devices allows me to workaround the problem and bring the machine to a clean shutdown. Caps lock led gets switched on -- doesn't blink. I think that leds blinking on oops is a kernel build option anyway. $ cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Core(TM)2 Duo CPU T7500 @ 2.20GHz stepping : 10 cpu MHz : 2201.000 cache size : 4096 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm bogomips : 4393.44 clflush size : 64 processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Core(TM)2 Duo CPU T7500 @ 2.20GHz stepping : 10 cpu MHz : 2201.000 cache size : 4096 KB physical id : 0 siblings : 2 core id : 1 cpu cores : 2 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm bogomips : 4388.83 clflush size : 64 Snippet of kern.log: Aug 6 19:21:22 aporo2 kernel: [32311.760000] Disabling non-boot CPUs ... Aug 6 19:21:22 aporo2 kernel: [32311.876000] CPU 1 is now offline Aug 6 19:21:22 aporo2 kernel: [32311.876000] SMP alternatives: switching to UP code Aug 6 19:21:22 aporo2 kernel: [32311.876000] CPU1 is down Aug 6 19:21:22 aporo2 kernel: [32311.876000] PM: Entering mem sleep Aug 6 19:21:22 aporo2 kernel: [32311.876000] Back to C! Aug 6 19:21:22 aporo2 kernel: [32311.876000] PM: Finishing wakeup. Aug 6 19:21:22 aporo2 kernel: [32311.876000] Enabling non-boot CPUs ... Aug 6 19:21:22 aporo2 kernel: [32311.888000] SMP alternatives: switching to SMP code Aug 6 19:21:22 aporo2 kernel: [32311.888000] Booting processor 1/1 eip 3000 Aug 6 19:21:22 aporo2 kernel: [32311.896000] Initializing CPU#1 Aug 6 19:21:22 aporo2 kernel: [32311.896000] BUG: unable to handle kernel paging request at virtual address 6a494846 Aug 6 19:21:22 aporo2 kernel: [32311.896000] printing eip: Aug 6 19:21:22 aporo2 kernel: [32311.896000] c01fd3cb Aug 6 19:21:22 aporo2 kernel: [32311.896000] *pde = 00000000 Aug 6 19:21:22 aporo2 kernel: [32311.896000] Oops: 0000 [#1] Aug 6 19:21:22 aporo2 kernel: [32311.896000] SMP Aug 6 19:21:22 aporo2 kernel: [32311.896000] Modules linked in: michael_mic arc4 ecb blkcipher ieee80211_crypt_tkip binfmt_misc capability ipv6 acpi_cpufreq cpufr eq_conservative cpufreq_ondemand cpufreq_userspace cpufreq_powersave cpufreq_stats freq_table container button dock sbs battery ac video sbp2 lp snd_hda_intel snd_ pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq pcmcia snd_timer snd_seq_device ieee80211_crypt snd sou ndcore xpad af_packet pcspkr hci_usb yenta_socket rsrc_nonstatic bluetooth tpm_infineon tpm tpm_bios snd_page_alloc parport_pc parport pcmcia_core serio_raw psmous e shpchp pci_hotplug intel_agp agpgart joydev evdev ext3 jbd mbcache sg usbhid hid sd_mod ahci ohci1394 ieee1394 ata_generic ehci_hcd libata scsi_mod uhci_hcd usbc ore thermal processor fan apparmor commoncap aamatch_pcre Aug 6 19:21:22 aporo2 kernel: [32311.896000] CPU: 1 Aug 6 19:21:22 aporo2 kernel: [32311.896000] EIP: 0060:[strstr+27/80] Not tainted VLI Aug 6 19:21:22 aporo2 kernel: [32311.896000] EFLAGS: 00010046 (2.6.22-9-generic #1) Aug 6 19:21:22 aporo2 kernel: [32311.896000] EIP is at strstr+0x1b/0x50 Aug 6 19:21:22 aporo2 kernel: [32311.896000] eax: 00000000 ebx: 6a494846 ecx: ffffffff edx: 6a494846 Aug 6 19:21:22 aporo2 kernel: [32311.896000] esi: c03c4ac4 edi: 6a494846 ebp: 00000001 esp: df839f24 Aug 6 19:21:22 aporo2 kernel: [32311.896000] ds: 007b es: 007b fs: 00d8 gs: 0000 ss: 0068 Aug 6 19:21:22 aporo2 kernel: [32311.896000] Process swapper (pid: 0, ti=df838000 task=df830a40 task.ti=df838000) Aug 6 19:21:22 aporo2 kernel: [32311.896000] Stack: 00000001 c04082cc 00000000 c0271fc4 00000001 01000000 00000000 c01018e1 Aug 6 19:21:22 aporo2 kernel: [32311.896000] 00000280 00000320 c01180df 00000001 40002073 c0438000 ffffffff c010b60d Aug 6 19:21:22 aporo2 kernel: [32311.896000] 00050014 c0371e40 00000001 c2008900 01bd0000 00000001 01000000 00000000 Aug 6 19:21:22 aporo2 kernel: [32311.896000] Call Trace: Aug 6 19:21:22 aporo2 kernel: [32311.896000] [dmi_check_system+52/112] dmi_check_system+0x34/0x70 Aug 6 19:21:22 aporo2 kernel: [32311.896000] [calibrate_delay+17/1840] calibrate_delay+0x11/0x730 Aug 6 19:21:22 aporo2 kernel: [32311.896000] [setup_local_APIC+655/672] setup_local_APIC+0x28f/0x2a0 Aug 6 19:21:22 aporo2 kernel: [32311.896000] [cpu_init+413/592] cpu_init+0x19d/0x250 Aug 6 19:21:22 aporo2 kernel: [32311.896000] [start_secondary+181/896] start_secondary+0xb5/0x380 Aug 6 19:21:22 aporo2 kernel: [32311.896000] [cpu_exit_clear+25/64] cpu_exit_clear+0x19/0x40 Aug 6 19:21:22 aporo2 kernel: [32311.896000] [] acpi_processor_idle+0x0/0x41f [processor] Aug 6 19:21:22 aporo2 kernel: [32311.896000] [cpu_idle+172/224] cpu_idle+0xac/0xe0 Aug 6 19:21:22 aporo2 kernel: [32311.896000] ======================= Aug 6 19:21:22 aporo2 kernel: [32311.896000] Code: 5b c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 83 ec 0c b9 ff ff ff ff 89 1c 24 89 d3 89 74 24 04 89 c6 31 c0 89 7c 24 08 89 df ae f7 d1 49 89 ca 89 df 89 f0 89 d1 f3 a6 74 0a 96 46 80 78 Aug 6 19:21:22 aporo2 kernel: [32311.896000] EIP: [strstr+27/80] strstr+0x1b/0x50 SS:ESP 0068:df839f24 Aug 6 19:21:22 aporo2 kernel: [32311.896000] Kernel panic - not syncing: Attempted to kill the idle task! Aug 6 19:21:22 aporo2 kernel: [32320.412000] Stuck ?? Aug 6 19:21:22 aporo2 kernel: [32320.412000] Inquiring remote APIC #1... Aug 6 19:21:22 aporo2 kernel: [32320.412000] ... APIC #1 ID: failed Aug 6 19:21:22 aporo2 kernel: [32320.412000] ... APIC #1 VERSION: failed Aug 6 19:21:22 aporo2 kernel: [32320.412000] ... APIC #1 SPIV: failed Aug 6 19:21:22 aporo2 kernel: [32320.412000] skipping cpu1, didn't come online Aug 6 19:21:22 aporo2 kernel: [32320.412000] Error taking CPU1 up: -5 Aug 6 19:21:22 aporo2 kernel: [32320.440000] APIC error on CPU0: 00(40)