2) Or use the system kernel binary itself as dump-capture kernel and there is
no need to build a separate dump-capture kernel. This is possible
only with the architecutres which support a relocatable kernel. As
- of today i386 and ia64 architectures support relocatable kernel.
+ of today, i386, x86_64 and ia64 architectures support relocatable kernel.
Building a relocatable kernel is advantageous from the point of view that
one does not have to build a second kernel for capturing the dump. But
any space below the alignment point will be wasted.
+Extended crashkernel syntax
+===========================
+
+While the "crashkernel=size[@offset]" syntax is sufficient for most
+configurations, sometimes it's handy to have the reserved memory dependent
+on the value of System RAM -- that's mostly for distributors that pre-setup
+the kernel command line to avoid a unbootable system after some memory has
+been removed from the machine.
+
+The syntax is:
+
+ crashkernel=<range1>:<size1>[,<range2>:<size2>,...][@offset]
+ range=start-[end]
+
+ 'start' is inclusive and 'end' is exclusive.
+
+For example:
+
+ crashkernel=512M-2G:64M,2G-:128M
+
+This would mean:
+
+ 1) if the RAM is smaller than 512M, then don't reserve anything
+ (this is the "rescue" case)
+ 2) if the RAM size is between 512M and 2G (exclusive), then reserve 64M
+ 3) if the RAM size is larger than 2G, then reserve 128M
+
+
+
Boot into System Kernel
=======================