On 10.12.2024 15:29, Frediano Ziglio wrote: > On Tue, Dec 10, 2024 at 10:14 AM Jan Beulich <jbeul...@suse.com> wrote: >> >> On 22.11.2024 10:33, Frediano Ziglio wrote: >>> Not all headers can be used by 32 bit boot code. >>> Allows to override some headers, we don't want to mess up with >>> main headers as most of the code is only 64 bit so the easy stuff should >>> be done for 64 bit declarations. >>> Boot headers should be 64 bit compatibles to avoid having multiple >>> declarations. >> >> I'm afraid that in isolation it's not clear what is intended. Boot code is >> all located in a single directory. Can't we use local headers there, using >> #include "...", instead of ... >> > > That approach was refused.
Can you provide a reference please? > Some definitions are in the headers (like > CPU features for instance) but duplicating the definitions was > rejected as a solution. > So the idea is to reuse such definitions. But, as stated in the > comment, the "x86" includes are not for x86, but most of them are just > for x64.This for historic reasons. But most of the code is x64 only so > changing headers to be x86 compatible would complicate them for a > minimal gain. Yet the amount of what wants sharing ought to be low. It might even help to clarify what it is that is meant to become shared. >>> --- a/xen/arch/x86/boot/Makefile >>> +++ b/xen/arch/x86/boot/Makefile >>> @@ -18,7 +18,7 @@ CFLAGS_x86_32 := $(subst -m64,-m32 >>> -march=i686,$(XEN_TREEWIDE_CFLAGS)) >>> $(call cc-options-add,CFLAGS_x86_32,CC,$(EMBEDDED_EXTRA_CFLAGS)) >>> CFLAGS_x86_32 += -Werror -fno-builtin -g0 -msoft-float -mregparm=3 >>> CFLAGS_x86_32 += -nostdinc -include $(filter >>> %/include/xen/config.h,$(XEN_CFLAGS)) >>> -CFLAGS_x86_32 += $(filter -I% -O%,$(XEN_CFLAGS)) -D__XEN__ >>> +CFLAGS_x86_32 += -I$(srctree)/arch/x86/include/boot $(filter -I% >>> -O%,$(XEN_CFLAGS)) -D__XEN__ >> >> ... introducing a arch-wide subdir, which non-boot code could easily (ab)use? > > You would have to explicitly add the "boot" into the path, No different from "hvm" or "guest", just to give two examples. > it does not > seem "easy" to me, but if you really want to do it you can do with > these or any other headers, like simply "#include "../arch/arm/..." in > x64 code. Same easiness. Well, no, the ".." in #include directives certainly stands out. Jan
