Re: [PATCH 4/8] symbols/ppc: don't use symbols-dummy

[Timothy Pearson <tpearson@xxxxxxxxxxxxxxxxxxxxx>]

----- Original Message -----
> From: "Jan Beulich" <jbeulich@xxxxxxxx>
> To: "xen-devel" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
> Cc: "Andrew Cooper" <andrew.cooper3@xxxxxxxxxx>, "Julien Grall" 
> <julien@xxxxxxx>, "Stefano Stabellini"
> <sstabellini@xxxxxxxxxx>, "Anthony PERARD" <anthony.perard@xxxxxxxxxx>, 
> "Michal Orzel" <michal.orzel@xxxxxxx>, "Roger
> Pau Monné" <roger.pau@xxxxxxxxxx>, "Timothy Pearson" 
> <tpearson@xxxxxxxxxxxxxxxxxxxxx>
> Sent: Wednesday, November 26, 2025 7:43:46 AM
> Subject: [PATCH 4/8] symbols/ppc: don't use symbols-dummy

> In particular when linking with lld, which converts hidden symbols to
> local ones, the ELF symbol table can change in unhelpful ways between the
> first two linking passes, resulting in the .rodata contributions to change
> between the 2nd and 3rd pass. That, however, renders our embedded symbol
> table pretty much unusable; the recently introduced self-test may then
> also fail. (Another difference between compiling a C file and assembling
> the generated ones is that - with -fdata-sections in use - the .rodata
> contributions move between passes 1 and 2, when we'd prefer them not to.)
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

Looks good to me.  Thanks!

Acked-by: Timothy Pearson <tpearson@xxxxxxxxxxxxxxxxxxxxx>

> --- a/xen/arch/ppc/Makefile
> +++ b/xen/arch/ppc/Makefile
> @@ -12,8 +12,10 @@ $(TARGET): $(TARGET)-syms
>       cp -f $< $@
> 
> $(TARGET)-syms: $(objtree)/prelink.o $(obj)/xen.lds
> +     $(objtree)/tools/symbols $(all_symbols) --empty > $(dot-target).0.S
> +     $(MAKE) $(build)=$(@D) $(dot-target).0.o
>       $(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds $< \
> -         $(objtree)/common/symbols-dummy.o -o $(dot-target).0
> +           $(dot-target).0.o -o $(dot-target).0
>       $(NM) -pa --format=sysv $(dot-target).0 \
>               | $(objtree)/tools/symbols $(all_symbols) --sysv --sort \
>               > $(dot-target).1.S