CPU failed to start Panics Seen on Reboots in Elastic Mode

Bug ID 6852379: Under rare circumstances, when Power Management mode is set to elastic, a domain that is booting might panic very early in its boot sequence with messages similar to one of the following:

Boot device: /virtual-devices@100/channel-devices@200/disk@0  File and args:
SunOS Release 5.10 Version Generic_139555-08 64-bit
Copyright 1983-2009 Sun Microsystems, Inc.  All rights reserved.
Use is subject to license terms.

panic[cpu0]/thread=180e000: cpu1 failed to start (2)

Or:

Boot device: /virtual-devices@100/channel-devices@200/disk@0  File and args:
SunOS Release 5.10 Version Generic_139555-08 64-bit
Copyright 1983-2009 Sun Microsystems, Inc.  All rights reserved.
Use is subject to license terms.

panic[cpu0]/thread=180e000: XC SPL ENTER already entered (0x0)

Impact: Because the panic occurs very early in the boot sequence, it has no impact on applications or file systems because they have not yet been started. The domain should automatically reboot. Note that the domain might not reboot because of CR 6853590, see Reboot Stops at OpenBoot Prompt When Services Cannot Be Initialized.

Workaround: If the domain fails to boot, do one of the following:

• Stop and start the impacted domain while the system is in elastic mode

• Configure the Power Management mode from elastic to performance mode, boot the domain, and then return the system to elastic mode