Am Mittwoch, 06 Juli 2016, 16:52:19 schrieb AKASHI Takahiro:
On the startup of primary kernel, the memory region used by crash dump
kernel must be specified by "crashkernel=" kernel parameter.
reserve_crashkernel() will allocate and reserve the region for later use.
User space tools, like kexec-tools, will be able to find that region
marked as "Crash kernel" in /proc/iomem.
On powerpc, userspace tools get everything from the device tree (exposed to
userspace in /proc/device-tree/), not /proc/iomem.
In the case of the crashkernel reserved region, that information is in
/chosen/linux,crashkernel-base and /chosen/linux,crashkernel-size.
Either way is fine I think. I'm just mentioning this for reference in case
you want the ARM implementation to be closer to another arch which is also
based on the device tree.
--
[]'s
Thiago Jung Bauermann
IBM Linux Technology Center