On Fri, May 26, Ian Jackson wrote:

> This seems like a real problem which should be improved.  But maybe we
> should use Xen's EXTRAVERSION by default ?

After thinking about it, why does the tools build not just enforce a
fixed string? There is no point for scripts/buildversion.py to put
current time and buildhost into the binary. This breaks reproducible
builds. A simple, untested change like this should be enough:

diff --git a/tools/firmware/Makefile b/tools/firmware/Makefile
index 8562f547bc..c2b5985dc7 100644
--- a/tools/firmware/Makefile
+++ b/tools/firmware/Makefile
@@ -22,6 +22,8 @@ ovmf-dir:
 seabios-dir:
 	GIT=$(GIT) $(XEN_ROOT)/scripts/git-checkout.sh $(SEABIOS_UPSTREAM_URL) $(SEABIOS_UPSTREAM_REVISION) seabios-dir
 	cp seabios-config seabios-dir/.config;
+	rm -f seabios-dir/.version
+	echo '$(SEABIOS_UPSTREAM_REVISION)' > seabios-dir/.version
 	$(MAKE) -C seabios-dir olddefconfig
 
 .PHONY: all
@@ -35,7 +37,7 @@ ifeq ($(CONFIG_ROMBIOS),y)
 	false ; \
 	fi
 endif
-	$(MAKE) $(LD32BIT-y) CC=$(CC) PYTHON=$(PYTHON) subdirs-$@
+	$(MAKE) $(LD32BIT-y) CC=$(CC) PYTHON=$(PYTHON) EXTRAVERSION="-Xen" subdirs-$@
 
 
 .PHONY: install

Olaf