[PATCH v10 2/2] xen: Strip xen.efi by default

[Frediano Ziglio <frediano.ziglio@citrix.com>]

From: Frediano Ziglio <frediano.ziglio@cloud.com>

For xen.gz file we strip all symbols and have an additional
xen-syms.efi file version with all symbols.
Make xen.efi more coherent stripping all symbols too.
xen-syms.efi can be used for debugging.

Signed-off-by: Frediano Ziglio <frediano.ziglio@cloud.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>
---
Changes since v1:
- avoid leaving target if some command fails.

Changes since v2:
- do not convert type but retain PE format;
- use xen-syms.efi for new file name, more consistent with ELF.

Changes since v3:
- update documentation;
- do not remove xen.efi.elf;
- check endbr instruction before generating final target.

Changes since v4:
- simplify condition check;
- avoid reuse of $@.tmp file.

Changes since v5:
- avoid creation of temporary file.

Changes since v6:
- install xen-syms.efi;
- always strip xen.efi;
- restore EFI_LDFLAGS check during rule execution;
- update CHANGELOG.md;
- added xen-syms.efi to .gitignore.

Changes since v7:
- move and improve CHANGELOG.md changes.

Changes since v8:
- rebase on master;
- clean xen-syms.efi file.

Changes since v9:
- Move changelog change to 4.22.
---
 .gitignore            |  1 +
 CHANGELOG.md          |  4 ++++
 docs/misc/efi.pandoc  |  8 +-------
 xen/Kconfig.debug     |  9 ++-------
 xen/Makefile          | 25 +++----------------------
 xen/arch/x86/Makefile | 12 +++++++++---
 6 files changed, 20 insertions(+), 39 deletions(-)

diff --git a/.gitignore b/.gitignore
index 57d54f676f..f282192b3e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -223,6 +223,7 @@ tools/flask/policy/xenpolicy-*
 xen/xen
 xen/suppression-list.txt
 xen/xen-syms
+xen/xen-syms.efi
 xen/xen-syms.map
 xen/xen.*
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3aaf598623..d15988fe1f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 ## [4.22.0 UNRELEASED](https://xenbits.xenproject.org/gitweb/?p=xen.git;a=shortlog;h=staging) - TBD
 
 ### Changed
+ - On x86:
+   - The install-time environment variable INSTALL_EFI_STRIP no longer exists.
+     xen.efi is always stripped, while the symbols remain available in
+     xen-syms.efi.
 
 ### Added
 
diff --git a/docs/misc/efi.pandoc b/docs/misc/efi.pandoc
index 11c1ac3346..c66b18a66b 100644
--- a/docs/misc/efi.pandoc
+++ b/docs/misc/efi.pandoc
@@ -20,13 +20,7 @@ Xen to load the configuration file even if multiboot modules are found.
 Once built, `make install-xen` will place the resulting binary directly into
 the EFI boot partition, provided `EFI_VENDOR` is set in the environment (and
 `EFI_MOUNTPOINT` is overridden as needed, should the default of `/boot/efi` not
-match your system). When built with debug info, the binary can be quite large.
-Setting `INSTALL_EFI_STRIP=1` in the environment will cause it to be stripped
-of debug info in the process of installing. `INSTALL_EFI_STRIP` can also be set
-to any combination of options suitable to pass to `strip`, in case the default
-ones don't do. The xen.efi binary will also be installed in `/usr/lib64/efi/`,
-unless `EFI_DIR` is set in the environment to override this default. This
-binary will not be stripped in the process.
+match your system).
 
 The binary itself will require a configuration file (names with the `.efi`
 extension of the binary's name replaced by `.cfg`, and - until an existing
diff --git a/xen/Kconfig.debug b/xen/Kconfig.debug
index d900d926c5..1a8e0c6ec3 100644
--- a/xen/Kconfig.debug
+++ b/xen/Kconfig.debug
@@ -147,12 +147,7 @@ config DEBUG_INFO
 	  Say Y here if you want to build Xen with debug information. This
 	  information is needed e.g. for doing crash dump analysis of the
 	  hypervisor via the "crash" tool.
-	  Saying Y will increase the size of the xen-syms and xen.efi
-	  binaries. In case the space on the EFI boot partition is rather
-	  limited, you may want to install a stripped variant of xen.efi in
-	  the EFI boot partition (look for "INSTALL_EFI_STRIP" in
-	  docs/misc/efi.pandoc for more information - when not using
-	  "make install-xen" for installing xen.efi, stripping needs to be
-	  done outside the Xen build environment).
+	  Saying Y will increase the size of the xen-syms, xen-syms.efi and
+	  xen.efi.elf binaries.
 
 endmenu
diff --git a/xen/Makefile b/xen/Makefile
index e6cf287425..c2f1f84aae 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -491,22 +491,6 @@ 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(s) below
-# will be used. Otherwise, INSTALL_EFI_STRIP value will be used as the
-# option(s) to the strip command.
-ifdef INSTALL_EFI_STRIP
-
-ifeq ($(INSTALL_EFI_STRIP),1)
-efi-strip-opt := --strip-debug --keep-file-symbols
-else
-efi-strip-opt := $(INSTALL_EFI_STRIP)
-endif
-
-endif
-
 .PHONY: _install
 _install: D=$(DESTDIR)
 _install: T=$(notdir $(TARGET))
@@ -524,18 +508,15 @@ _install: $(TARGET)$(CONFIG_XEN_INSTALL_SUFFIX)
 	if [ -r $(TARGET).efi -a -n '$(EFI_DIR)' ]; then \
 		[ -d $(D)$(EFI_DIR) ] || $(INSTALL_DIR) $(D)$(EFI_DIR); \
 		$(INSTALL_DATA) $(TARGET).efi $(D)$(EFI_DIR)/$(T)-$(XEN_FULLVERSION).efi; \
-		for x in map elf; do \
-			if [ -e $(TARGET).efi.$$x ]; then \
-				$(INSTALL_DATA) $(TARGET).efi.$$x $(D)$(DEBUG_DIR)/$(T)-$(XEN_FULLVERSION).efi.$$x; \
+		for x in .efi.map .efi.elf -syms.efi; do \
+			if [ -e $(TARGET)$$x ]; then \
+				$(INSTALL_DATA) $(TARGET)$$x $(D)$(DEBUG_DIR)/$(T)-$(XEN_FULLVERSION)$$x; \
 			fi; \
 		done; \
 		ln -sf $(T)-$(XEN_FULLVERSION).efi $(D)$(EFI_DIR)/$(T)-$(XEN_VERSION).$(XEN_SUBVERSION).efi; \
 		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 ||) \
 			$(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; \
diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index 300cc67407..ee787068f8 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -232,12 +232,17 @@ endif
 	$(MAKE) $(build)=$(@D) .$(@F).2r.o .$(@F).2s.o
 	$(LD) $(call EFI_LDFLAGS,$(VIRT_BASE)) -T $(obj)/efi.lds $< \
 	      $(dot-target).2r.o $(dot-target).2s.o $(orphan-handling-y) \
-	      $(note_file_option) -o $@
-	$(NM) -pa --format=sysv $@ \
+	      $(note_file_option) -o $(TARGET)-syms.efi
+	$(NM) -pa --format=sysv $(TARGET)-syms.efi \
 		| $(objtree)/tools/symbols --all-symbols --xensyms --sysv --sort \
 		> $@.map
 ifeq ($(CONFIG_DEBUG_INFO),y)
-	$(if $(filter --strip-debug,$(EFI_LDFLAGS)),:$(space))$(OBJCOPY) -O elf64-x86-64 $@ $@.elf
+	$(if $(filter --strip-debug,$(EFI_LDFLAGS)),:$(space))$(OBJCOPY) \
+		-O elf64-x86-64 $(TARGET)-syms.efi $@.elf
+endif
+	$(STRIP) $(TARGET)-syms.efi -o $@
+ifneq ($(CONFIG_DEBUG_INFO),y)
+	rm -f $(TARGET)-syms.efi
 endif
 	rm -f $(dot-target).[0-9]* $(@D)/..$(@F).[0-9]*
 ifeq ($(CONFIG_XEN_IBT),y)
@@ -281,6 +286,7 @@ $(obj)/xen.lds $(obj)/efi.lds: $(src)/xen.lds.S FORCE
 clean-files := \
     include/asm/asm-macros.* \
     $(objtree)/.xen-syms.[0-9]* \
+    $(objtree)/xen-syms.efi \
     $(objtree)/.xen.elf32 \
     $(objtree)/.xen.efi.[0-9]* \
     efi/*.efi
-- 
2.43.0