KVM guests with less than 4 GB of memory might fail to auto reserve crash kernel memory
KVM guests that are running UEK R4 might fail to auto reserve
memory for a crash kernel if the
crashkernel=auto
setting is used on a guest
with less than 4 GB of physical memory.
To prevent this problem from occurring on KVM guests with less
than 4 GB of physical memory, you can reserve memory for a crash
kernel by explicitly requesting a reservation size, for example,
crashkernel=128M
. (Bug ID 26933217 )