Re: [Minios-devel] [UNIKRAFT PATCHv5 16/46] plat/kvm: Generate linker scripts from source code

[Simon Kuenzer <simon.kuenzer@xxxxxxxxx>]

On 07.09.2018 07:40, Wei Chen (Arm Technology China) wrote:
> Hi Simon,
>
> > -----Original Message-----
> > From: Simon Kuenzer <simon.kuenzer@xxxxxxxxx>
> > Sent: 2018年9月6日 23:50
> > To: Wei Chen (Arm Technology China) <Wei.Chen@xxxxxxx>; minios-
> > devel@xxxxxxxxxxxxxxxxxxxx
> > Cc: Kaly Xin (Arm Technology China) <Kaly.Xin@xxxxxxx>; nd <nd@xxxxxxx>
> > Subject: Re: [Minios-devel] [UNIKRAFT PATCHv5 16/46] plat/kvm: Generate linker
> > scripts from source code
> >
> > Hey Wei,
> >
> > I am currently thinking of a nicer solution for linker scripts that have
> > to be pre-processed. I think also other platforms could benefit from
> > something like this. The build system should provide you an easy way to
> > let you do this. Let me come up with a patch tomorrow to achieve this.
> > You could then just use this one.
> Oh, that would be better if we have a common solution for all platform : )
>
> > On 10.08.2018 09:08, Wei Chen wrote:
> > > Sometimes, using a macro in linker script will be easier for people
> > > to see what is done. This means we will share macros with source code.
> > > So, generate linker script from a .S will help linker script to share
> > > macros with source code.
> > >
> > > Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
> > > ---
> > >    plat/kvm/Linker.uk                       | 7 +++++--
> > >    plat/kvm/x86/{link64.ld => link64.lds.S} | 0
> > >    2 files changed, 5 insertions(+), 2 deletions(-)
> > >    rename plat/kvm/x86/{link64.ld => link64.lds.S} (100%)
> > >
> > > diff --git a/plat/kvm/Linker.uk b/plat/kvm/Linker.uk
> > > index 2292b03..fbadde2 100644
> > > --- a/plat/kvm/Linker.uk
> > > +++ b/plat/kvm/Linker.uk
> > > @@ -1,5 +1,6 @@
> > >    ifeq (x86_64,$(CONFIG_UK_ARCH))
> > > -KVM_LDSCRIPT  := -Wl,-T,$(CONFIG_UK_BASE)/plat/kvm/x86/link64.ld
> > > +KVM_LDSCRIPT  := -Wl,-T,$(CONFIG_UK_BASE)/plat/kvm/x86/link64.lds
> > > +KVM_LDSCRIPT_FLAGS := -Wl,-T,$(KVM_LDSCRIPT)
> > >    KVM_LDFLAGS-y += -Wl,-m,elf_x86_64
> > >    endif
> > >
> > > @@ -14,8 +15,10 @@ $(KVM_IMAGE): $(KVM_LINK) $(KVM_LINK-y) $(UK_LINK)
> > $(UK_LINK-y)
> > >         $(call build_cmd,OBJCOPY,,$@.o,\
> > >                $(OBJCOPY) -w -G kvmos_* -G _libkvmplat_entry $@.ld.o $@.o)
> > >    ifeq (x86_64,$(CONFIG_UK_ARCH))
> > > +       $(call build_cmd,CC,,link64.lds.o,\
> > > +              $(CC) -E $(ASINCLUDES) $(ASFLAGS) $(ASFLAGS-y) -P
> > $(KVM_LDSCRIPT).S -o $(KVM_LDSCRIPT))
> >
> > This rule says that the generated linker script is not saved to the
> > build directory. We should definitely avoid this since multiple projects
> > may use the same unikraft source base. Project configurations may result
> > in different linker scripts. Because of this, each project has its own
> > build directory.
> Yes, this would be a problem. Should I fix it in my patch or will you cover
> it in your new patch?
I will send the patch, try to get it in quickly, and then you can just 
use the introduced mechanism in this patch.
> > >         $(call build_cmd,LD,,$@,\
> > > -              $(LD) $(LDFLAGS) $(LDFLAGS-y) $(KVM_LDFLAGS) $(KVM_LDFLAGS-y)
> > $(KVM_LDSCRIPT) $@.o -o $@)
> > > +              $(LD) $(LDFLAGS) $(LDFLAGS-y) $(KVM_LDFLAGS) $(KVM_LDFLAGS-y)
> > $(KVM_LDSCRIPT_FLAGS) $@.o -o $@)
> > >    ifeq ($(CONFIG_OPTIMIZE_DBGFILE),y)
> > >         $(call build_cmd,OBJCOPY,,$@.dbg,\
> > >                $(OBJCOPY) --only-keep-debug $@ $@.dbg)
> > > diff --git a/plat/kvm/x86/link64.ld b/plat/kvm/x86/link64.lds.S
> > > similarity index 100%
> > > rename from plat/kvm/x86/link64.ld
> > > rename to plat/kvm/x86/link64.lds.S
> > Thanks,
> >
> > Simon
_______________________________________________
Minios-devel mailing list
Minios-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/minios-devel