On Thu, 2010-07-15 at 00:21 -0600, Grant Likely wrote:

On Wed, Jul 14, 2010 at 9:18 AM, Matthew McClintock
[off-list ref] wrote:

quoted

To build a proper flat device tree for kexec we need to know which
memreserve region was used for the device tree for the currently
running kernel, so we can remove it and replace it with the new
memreserve for the kexec'ed kernel

Signed-off-by: Matthew McClintock <redacted>

Hi Matthew.

I don't understand.  Why does userspace need to know about the old
memreserve sections?  Doesn't kexec tear down all of the old
allocations anyway?  How are they relevant for constructing the dtb
for the kexec kernel?  I'll need a lot more details before I consider
merging this.

Also, please cc: me and Ben Herrenschmidt on powerpc related device
tree changes.

Cheers,
g. 

Grant,

Thanks for taking a look. My first thought was to just blow away all the
memreserve regions and start over. But, there are reserve regions for
other things that I might not want to blow away. For example, on mpc85xx
SMP systems we have an additional reserve region for our boot page. 

There is already precedence for exporting the initrd physical addresses
in the same fashion, which is mostly why I took this route. So instead I
just choose to find and replace the device tree and initrd reserve
regions.

I'm open to other ideas, just let me know. 

Regards,
Matthew