[PATCH] kexec:arm: support zImage with appended device tree

[Hoeun Ryu]

> On Jun 27, 2017, at 5:53 PM, Russell King <rmk at armlinux.org.uk> wrote:
> 
>> On Tue, Jun 27, 2017 at 11:36:43AM +0900, Hoeun Ryu wrote:
>> We have some cases when we would like to use different dtb from the
>> running system when using kexec and I think that's why kexec-tools
>> supports --dtb command line option.
>> 
>> For example, I have the second kernel for the crash dump with different
>> kernel configuration and the different dtb from the running system. I'd
>> like to exclude some nodes/properties from dtb like memory reservations
>> or unnecessary devices to keep the second kernel/dtb minimal.
>> 
>> The concatenated zImage for arm has a benefit (whether it's intended or
>> not) to make it possible for users to merge multiple boot images into a
>> simple single file.
>> What I'd like to do is just to support the concatenated zImage so that
>> users can use --load(-panic) zImage_with_dtb_from_the_running_system
>> instead of --load(-panic) zImage --dtb
>> different_dtb_from_the_running_system.
> 
> Don't you mean --load(-panic) zImage_with_different_dtb_from_the_running_system
> ?
> 

I'm sorry. This is what I mean.

> So, what you seem to be saying is that you think it's easier for the user
> to do this:
> 
> # cat zImage some-other-dtb > zImage.dtb
> # kexec --load-panic zImage.dtb
> 
> rather than:
> 
> # kexec --load-panic zImage --dtb some-other-dtb
> 
> ?

Right.

> What about the initrd?  Do you want to append that as well?

I have thought of it.
I think It would be better to have it.
But I think this is the first step to do so.

> 
> -- 
> Russell King