On Thu, Jun 09, 2022 at 05:52:45PM +0200, Jan Beulich wrote: > With debug info retained, xen.efi can be quite large. Unlike for xen.gz > there's no intermediate step (mkelf32 there) involved which would strip > debug info kind of as a side effect. While the installing of xen.efi on > the EFI partition is an optional step (intended to be a courtesy to the > developer), adjust it also for the purpose of documenting what distros > would be expected to do during boot loader configuration (which is what > would normally put xen.efi into the EFI partition). > > Model the control over stripping after Linux'es module installation, > except that the stripped executable is constructed in the build area > instead of in the destination location. This is to conserve on space > used there - EFI partitions tend to be only a few hundred Mb in size. > > Signed-off-by: Jan Beulich <[email protected]> > --- > GNU strip 2.38 appears to have issues when acting on a PE binary: > - file name symbols are also stripped; while there is a separate > --keep-file-symbols option (which I would have thought to be on by > default anyway), its use so far makes no difference, > - the string table grows in size, when one would expect it to retain its > size (or shrink), > - linker version is changed in and timestamp zapped from the header. > Older GNU strip (observed with 2.35.1) doesn't work at all ("Data > Directory size (1c) exceeds space left in section (8)"). > > Future GNU strip is going to honor --keep-file-symbols (and will also > have the other issues fixed). Question is whether we should use that > option (for the symbol table as a whole to make sense), or whether > instead we should (by default) strip the symbol table as well.
I guess trying to keep those symbol might be useful, if it's not too big, to help debugging system in production. > --- a/xen/Makefile > +++ b/xen/Makefile > @@ -465,6 +465,22 @@ endif > .PHONY: _build > _build: $(TARGET)$(CONFIG_XEN_INSTALL_SUFFIX) > > +# Strip > +# > +# INSTALL_EFI_STRIP, if defined, will cause xen.efi to be stripped before it > +# is installed. If INSTALL_EFI_STRIP is '1', then the default option > +# --strip-debug will be used. Otherwise, INSTALL_EFI_STRIP value will be used > +# as the option(s) to the strip command. It would be useful to also document INSTALL_EFI_STRIP in ./INSTALL or in ./docs/misc/efi.pandoc (efi.pandoc is where EFI_VENDOR is documented for example, so probably a better place for the doc of the new option). > +ifdef INSTALL_EFI_STRIP > + > +ifeq ($(INSTALL_EFI_STRIP),1) > +efi-strip-opt := --strip-debug > +else > +efi-strip-opt := $(INSTALL_EFI_STRIP) > +endif > + > +endif > + > .PHONY: _install > _install: D=$(DESTDIR) > _install: T=$(notdir $(TARGET)) > @@ -489,6 +505,9 @@ _install: $(TARGET)$(CONFIG_XEN_INSTALL_ > ln -sf $(T)-$(XEN_FULLVERSION).efi > $(D)$(EFI_DIR)/$(T)-$(XEN_VERSION).efi; \ > ln -sf $(T)-$(XEN_FULLVERSION).efi $(D)$(EFI_DIR)/$(T).efi; \ > if [ -n '$(EFI_MOUNTPOINT)' -a -n '$(EFI_VENDOR)' ]; then \ > + $(if $(efi-strip-opt), \ > + $(STRIP) $(efi-strip-opt) -p -o > $(TARGET).efi.stripped $(TARGET).efi && \ > + $(INSTALL_DATA) $(TARGET).efi.stripped > $(D)$(EFI_MOUNTPOINT)/efi/$(EFI_VENDOR)/$(T)-$(XEN_FULLVERSION).efi ||) \ This optional part of the script that ends with "||" means that if `strip` or `install` fails, we would install the non stripped binary. Is this something that's acceptable? (Plus of doing that is avoiding changing the next line, and avoiding a longer $(if ,). > $(INSTALL_DATA) $(TARGET).efi > $(D)$(EFI_MOUNTPOINT)/efi/$(EFI_VENDOR)/$(T)-$(XEN_FULLVERSION).efi; \ > elif [ "$(D)" = "$(patsubst $(shell cd $(XEN_ROOT) && > pwd)/%,%,$(D))" ]; then \ > echo 'EFI installation only partially done (EFI_VENDOR > not set)' >&2; \ An other thing, the "*.efi.stripped" file is I think going to be left over and not removed during `make clean`. Cheers, -- Anthony PERARD
