Re: [XEN PATCH v4 15/18] xen/build: use if_changed to build guest_%.o

[Jan Beulich <jbeulich@xxxxxxxx>]

On 31.03.2020 12:30, Anthony PERARD wrote:
> Use if_changed for building all guest_%.o objects, and make use of
> command that already exist.
> 
> This patch make a change to the way guest_%.o files are built, and now
> run the same commands that enforce unique symbols. But with patch
> "xen,symbols: rework file symbols selection", ./symbols should still
> select the file symbols directive intended to be used for guest_%.o
> objects.

I'm having trouble making the connection between the change to the
symbols tool and the adjustments made here:

> --- a/xen/arch/x86/mm/Makefile
> +++ b/xen/arch/x86/mm/Makefile
> @@ -11,11 +11,13 @@ obj-y += p2m.o p2m-pt.o
>  obj-$(CONFIG_HVM) += p2m-ept.o p2m-pod.o
>  obj-y += paging.o
>  
> -guest_walk_%.o: guest_walk.c Makefile
> -     $(CC) $(c_flags) -DGUEST_PAGING_LEVELS=$* -c $< -o $@

The original rules didn't do anything special to arrange for the
resulting kallsyms names; these arrangements instead live at the
top of the respective source files, in the form of asm()-s.

Jan