9.25 Kernel Panic when Assigning More Than 32 virtual CPUs to Oracle Linux 32-bit PVM Guests

You cannot assign more than the 32 virtual CPUs to Oracle Linux 32-bit Paravirtualized (PVM) guests running Oracle Unbreakable Enterprise Kernel (UEK) Release 2. Oracle Linux 32-bit PVM guests running UEK Release 2 support a maximum of 32 virtual CPUs. If you assign more than the maximum virtual CPUs allowed, kernel panic may occur.

Workaround: Set the maximum virtual CPUs to 32 or less. Use the uname command to determine the UEK version you are running on the guest virtual machine and from the result, you can determine the maximum number of virtual CPUs supported, for example:

# uname -r
2.6.39-400.278.3.el6uek.i686
# cat config-2.6.39-400.278.3.el6uek.i686 | grep CONFIG_NR_CPUS
CONFIG_NR_CPUS=32

Bug 25745578