> Ananth forwarded me this mail as it has some mention of kexec. > In this posting you mentioned that the recent regset changes > you are planning might break kexec. > > Could you elaborate on this ? Also will these changes break > kexec only on powerpc or other arch also ?
Please see http://lkml.org/lkml/2008/1/18/583 No arch's kexec is affected unless it has removed its ELF_CORE_COPY_REGS macro. My x86 changes in the x86/mm tree did that, but it's now been added back to unbreak kexec. The powerpc patches I posted also remove the macro, but those patches haven't been incorporated anywhere yet anyway; it's simple just not to remove the macro (it's part of patch 10/16 in the powerpc patch series; patch 10 does nothing but remove old code, all of which but this is truly unused). As I mentioned in that lkml message, I think it would be better for kexec to clean up its arch interfaces not to use elf_core_copy_regs at all. There is already machine-specific kexec code that goes through contortions with register values, so it might as well be consolidated into a single set of contortions that produces the final data format (i.e. elf_gregset_t). But there is no big rush to resolve that. The machine-specific macro ELF_CORE_COPY_REGS no longer has any use for core files and it's unsightly to keep it around with that name, but that's all. kexec will not be broken by the user_regset changes when they are merged. If kexec cleaned up, that and user_regset support together would permit each arch to drop the ELF_CORE_COPY_REGS macro and cut down the clutter. Thanks, Roland
