File xen.ee41b5c450032ae7f2531e18cd0a73bf5fb48803.patch of Package xen

From: Maximilian Engelhardt <maxi@daemonizer.de>
Date: Tue, 22 Dec 2020 08:59:14 +0100
Subject: ee41b5c450032ae7f2531e18cd0a73bf5fb48803

x86/EFI: don't insert timestamp when SOURCE_DATE_EPOCH is defined

By default a timestamp gets added to the xen efi binary. Unfortunately
ld doesn't seem to provide a way to set a custom date, like from
SOURCE_DATE_EPOCH, so set a zero value for the timestamp (option
--no-insert-timestamp) if SOURCE_DATE_EPOCH is defined. This makes
reproducible builds possible.

This is an alternative to the patch suggested in [1]. This patch only
omits the timestamp when SOURCE_DATE_EPOCH is defined.

[1] https://lists.xenproject.org/archives/html/xen-devel/2020-10/msg02161.html

Signed-off-by: Maximilian Engelhardt <maxi@daemonizer.de>
Acked-by: Jan Beulich <jbeulich@suse.com>
---
 xen/arch/x86/Makefile | 6 ++++++
 1 file changed, 6 insertions(+)

--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -160,24 +160,30 @@ note.o: $(TARGET)-syms
 	$(OBJCOPY) -O binary --only-section=.note.gnu.build-id  $(BASEDIR)/xen-syms $@.bin
 	$(OBJCOPY) -I binary -O elf64-x86-64 -B i386:x86-64 \
 		--rename-section=.data=.note.gnu.build-id -S $@.bin $@
 	rm -f $@.bin
 
 EFI_LDFLAGS = $(patsubst -m%,-mi386pep,$(LDFLAGS)) --subsystem=10
 EFI_LDFLAGS += --image-base=$(1) --stack=0,0 --heap=0,0 --strip-debug
 EFI_LDFLAGS += --section-alignment=0x200000 --file-alignment=0x20
 EFI_LDFLAGS += --major-image-version=$(XEN_VERSION)
 EFI_LDFLAGS += --minor-image-version=$(XEN_SUBVERSION)
 EFI_LDFLAGS += --major-os-version=2 --minor-os-version=0
 EFI_LDFLAGS += --major-subsystem-version=2 --minor-subsystem-version=0
+# It seems ld unfortunately can't set a custom timestamp, so add a zero value
+# for the timestamp (option --no-insert-timestamp) if SOURCE_DATE_EPOCH is
+# defined to make reproducible builds possible.
+ifdef SOURCE_DATE_EPOCH
+EFI_LDFLAGS += --no-insert-timestamp
+endif
 
 # Check if the compiler supports the MS ABI.
 export XEN_BUILD_EFI := $(shell $(CC) $(filter-out $(CFLAGS-y) .%.d,$(CFLAGS)) -c efi/check.c -o efi/check.o 2>/dev/null && echo y)
 # Check if the linker supports PE.
 XEN_BUILD_PE := $(if $(XEN_BUILD_EFI),$(shell $(LD) $(call EFI_LDFLAGS,0x100000000) -o efi/check.efi efi/check.o 2>/dev/null && echo y))
 CFLAGS-$(XEN_BUILD_EFI) += -DXEN_BUILD_EFI
 # Check if the linker produces fixups in PE by default (we need to disable it doing so for now).
 XEN_NO_PE_FIXUPS := $(if $(XEN_BUILD_EFI), \
                          $(shell $(LD) $(call EFI_LDFLAGS,0x100000000) --disable-reloc-section -o efi/check.efi efi/check.o 2>/dev/null && \
                                  echo --disable-reloc-section))
 EFI_LDFLAGS += $(XEN_NO_PE_FIXUPS)