On Mon, 2017-06-26 at 10:14 +0100, Russell King wrote: > On Fri, Jun 23, 2017 at 05:55:38PM +0900, Hoeun Ryu wrote: > > > > Arm linux supports zImage with appended dtb > > (CONFIG_ARM_APPENDED_DTB) and > > the concatenated image is generated like `cat zImage dtb > > > zImage_w_dtb`. > We support that only for the purpose of allowing old boot loaders > that > are not DT aware to load kernels that require DT.??If it weren't for > that, we wouldn't have it. > > I don't see why we should propagate this hack to other systems such > as > kexec, especially when they have native DT support. > 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. Thank you for the review.
