Comment 143 for bug 191137

hp pavilion dv6500
Booting with kernel options:

without ac-power it hangs too
  after ac-power-button press (or wlan-button change) it boots further
  and hangs then later

[ 25.334075] ACPI: Battery Slot [BAT0] (battery present)
[ 25.335892] ACPI: WMI: Mapper loaded
[ 25.603699] ACPI: device:25 is registered as cooling_device2
[ 25.603699] input: Video Bus as /class/input/input7
[ 25.651769] ACPI: Video Device [UVGA] (multi-head: yes rom: no post: no)
[ 25.714598] pci_hotplug: PCI Hot Plug PCI Core version: 0.5
[ 25.908925] shpchp: Standard Hot Plug PCI Controller Driver version: 0.4
[ 26.165161] ricoh-mmc: Ricoh MMC Controller disabling driver
[ 26.166967] ricoh-mmc: Copyright(c) Philip Langdale
[ 26.169028] ricoh-mmc: Ricoh MMC controller found at 0000:02:05.2 [1180:0843] (rev 12)
[ 26.169047] ricoh-mmc: Controller is now disabled.
[ 26.230659] input: PC Speaker as /class/input/input8
[ 175.522250] BUG: soft lockup - CPU#1 stuck for 140s! [swapper:0]
[ 175.522250] Modules linked in: pcspkr(+) soundcore ricoh_mmc mmc_core k8temp shpchp pci_hotplug video output wmi battery ac button evdev ext3 jbd mbcache sg sr_mod sd_mod cdrom ata_generic pata_acpi usbhid hid pata_amd ahci ssb libata ohci1394 ehci_hcd ohci_hcd ieee1394 scsi_mod forcedeth dock usbcore thermal processor fan fuse
[ 175.522250]
[ 175.522250] Pid: 0, comm: swapper Not tainted (2.6.26-20080716 #2)
[ 175.522250] EIP: 0060:[<c01176a2>] EFLAGS: 00000246 CPU: 1
[ 175.522250] EIP is at native_safe_halt+0x2/0x10

175.52... then I re-connected the ac-power chord into the laptop