[PATCH v8] xen: Strip xen.efi by default

Frediano Ziglio posted 1 patch 5 days, 8 hours ago
Patches applied successfully (tree, apply log)
git fetch https://gitlab.com/xen-project/patchew/xen tags/patchew/20251113154358.28704-1-frediano.ziglio@citrix.com
.gitignore            |  1 +
CHANGELOG.md          |  3 +++
docs/misc/efi.pandoc  |  8 +-------
xen/Kconfig.debug     |  9 ++-------
xen/Makefile          | 25 +++----------------------
xen/arch/x86/Makefile | 11 ++++++++---
6 files changed, 18 insertions(+), 39 deletions(-)
[PATCH v8] xen: Strip xen.efi by default
Posted by Frediano Ziglio 5 days, 8 hours ago
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>
---
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.
---
 .gitignore            |  1 +
 CHANGELOG.md          |  3 +++
 docs/misc/efi.pandoc  |  8 +-------
 xen/Kconfig.debug     |  9 ++-------
 xen/Makefile          | 25 +++----------------------
 xen/arch/x86/Makefile | 11 ++++++++---
 6 files changed, 18 insertions(+), 39 deletions(-)

diff --git a/.gitignore b/.gitignore
index d83427aba8..213972b65c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -222,6 +222,7 @@ 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 c9932a2af0..bc16e316e7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -34,6 +34,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
      BAR for HVM guests, to improve performance of guests using it to map the
      grant table or foreign memory.
    - Allow configuring the number of altp2m tables per domain via vm.cfg.
+   - 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
  - Introduce new PDX compression algorithm to cope with Intel Sierra Forest and
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 fc9244420e..5ed029fed1 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -493,22 +493,6 @@ 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))
@@ -526,18 +510,15 @@ _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 407571c510..a154ffe6b2 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -228,12 +228,17 @@ endif
 	$(MAKE) $(build)=$(@D) .$(@F).1r.o .$(@F).1s.o
 	$(LD) $(call EFI_LDFLAGS,$(VIRT_BASE)) -T $(obj)/efi.lds $< \
 	      $(dot-target).1r.o $(dot-target).1s.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)
-- 
2.43.0
Re: [PATCH v8] xen: Strip xen.efi by default
Posted by Oleksii Kurochko 4 days, 8 hours ago
On 11/13/25 4:43 PM, Frediano Ziglio wrote:
> 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>

Release-Acked-By: Oleksii Kurochko<oleksii.kurochko@gmail.com>

Thanks.

~ Oleksii

> ---
> 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.
> ---
>   .gitignore            |  1 +
>   CHANGELOG.md          |  3 +++
>   docs/misc/efi.pandoc  |  8 +-------
>   xen/Kconfig.debug     |  9 ++-------
>   xen/Makefile          | 25 +++----------------------
>   xen/arch/x86/Makefile | 11 ++++++++---
>   6 files changed, 18 insertions(+), 39 deletions(-)
>
> diff --git a/.gitignore b/.gitignore
> index d83427aba8..213972b65c 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -222,6 +222,7 @@ 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 c9932a2af0..bc16e316e7 100644
> --- a/CHANGELOG.md
> +++ b/CHANGELOG.md
> @@ -34,6 +34,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
>        BAR for HVM guests, to improve performance of guests using it to map the
>        grant table or foreign memory.
>      - Allow configuring the number of altp2m tables per domain via vm.cfg.
> +   - 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
>    - Introduce new PDX compression algorithm to cope with Intel Sierra Forest and
> 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 fc9244420e..5ed029fed1 100644
> --- a/xen/Makefile
> +++ b/xen/Makefile
> @@ -493,22 +493,6 @@ 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))
> @@ -526,18 +510,15 @@ _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 407571c510..a154ffe6b2 100644
> --- a/xen/arch/x86/Makefile
> +++ b/xen/arch/x86/Makefile
> @@ -228,12 +228,17 @@ endif
>   	$(MAKE) $(build)=$(@D) .$(@F).1r.o .$(@F).1s.o
>   	$(LD) $(call EFI_LDFLAGS,$(VIRT_BASE)) -T $(obj)/efi.lds $< \
>   	      $(dot-target).1r.o $(dot-target).1s.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)
Re: [PATCH v8] xen: Strip xen.efi by default
Posted by Andrew Cooper 4 days, 5 hours ago
On 14/11/2025 3:40 pm, Oleksii Kurochko wrote:
>
>
> On 11/13/25 4:43 PM, Frediano Ziglio wrote:
>> 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>
> Release-Acked-By: Oleksii Kurochko <oleksii.kurochko@gmail.com>
>
> Thanks.

Thanks.  Unfortunately CI says no.

Ubuntu's 20.04, 18.04 and 16.04 all fail: 
https://gitlab.com/xen-project/hardware/xen-staging/-/pipelines/2159622869

From 16.04:

2025-11-14T18:01:51.192964Z 01O strip xen-syms.efi -o xen.efi
2025-11-14T18:01:51.198151Z 01O strip:xen-syms.efi[.init]: relocation count is negative: File truncated
2025-11-14T18:01:51.198166Z 01O strip: xen.efi: Failed to read debug data section
2025-11-14T18:01:51.198169Z 01O strip:xen.efi: error copying private BFD data: File truncated
2025-11-14T18:01:51.198932Z 01O arch/x86/Makefile:207: recipe for target 'xen.efi' failed
2025-11-14T18:01:51.198937Z 01O make[3]: *** [xen.efi] Error 1
2025-11-14T18:01:51.199616Z 01O build.mk:90: recipe for target 'xen' failed
2025-11-14T18:01:51.199619Z 01O make[2]: *** [xen] Error 2
2025-11-14T18:01:51.200402Z 01O Makefile:600: recipe for target 'xen' failed
2025-11-14T18:01:51.200409Z 01O make[1]: *** [xen] Error 2


I find it hard to believe that the relocation count is really negative,
and given that newer binuitls works, I expect this is a binutils bug.

Nevertheless, we need some workaround.  Given that the previous
behaviour was not to strip, I think we can reuse that for broken toolchains?

~Andrew

Re: [PATCH v8] xen: Strip xen.efi by default
Posted by Frediano Ziglio 3 days, 18 hours ago
On Fri, 14 Nov 2025 at 19:18, Andrew Cooper <andrew.cooper3@citrix.com> wrote:
>
> On 14/11/2025 3:40 pm, Oleksii Kurochko wrote:
> >
> >
> > On 11/13/25 4:43 PM, Frediano Ziglio wrote:
> >> 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>
> > Release-Acked-By: Oleksii Kurochko <oleksii.kurochko@gmail.com>
> >
> > Thanks.
>
> Thanks.  Unfortunately CI says no.
>
> Ubuntu's 20.04, 18.04 and 16.04 all fail:
> https://gitlab.com/xen-project/hardware/xen-staging/-/pipelines/2159622869
>
> From 16.04:
>
> 2025-11-14T18:01:51.192964Z 01O strip xen-syms.efi -o xen.efi
> 2025-11-14T18:01:51.198151Z 01O strip:xen-syms.efi[.init]: relocation count is negative: File truncated
> 2025-11-14T18:01:51.198166Z 01O strip: xen.efi: Failed to read debug data section
> 2025-11-14T18:01:51.198169Z 01O strip:xen.efi: error copying private BFD data: File truncated
> 2025-11-14T18:01:51.198932Z 01O arch/x86/Makefile:207: recipe for target 'xen.efi' failed
> 2025-11-14T18:01:51.198937Z 01O make[3]: *** [xen.efi] Error 1
> 2025-11-14T18:01:51.199616Z 01O build.mk:90: recipe for target 'xen' failed
> 2025-11-14T18:01:51.199619Z 01O make[2]: *** [xen] Error 2
> 2025-11-14T18:01:51.200402Z 01O Makefile:600: recipe for target 'xen' failed
> 2025-11-14T18:01:51.200409Z 01O make[1]: *** [xen] Error 2
>
>
> I find it hard to believe that the relocation count is really negative,
> and given that newer binuitls works, I expect this is a binutils bug.
>

Unless the message is just misleading I find it hard to have a
negative number of items in a container.

> Nevertheless, we need some workaround.  Given that the previous
> behaviour was not to strip, I think we can reuse that for broken toolchains?
>

Something like that ?

diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index a154ffe6b2..c465eb12e2 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -236,7 +236,9 @@ ifeq ($(CONFIG_DEBUG_INFO),y)
        $(if $(filter --strip-debug,$(EFI_LDFLAGS)),:$(space))$(OBJCOPY) \
                -O elf64-x86-64 $(TARGET)-syms.efi $@.elf
 endif
-       $(STRIP) $(TARGET)-syms.efi -o $@
+       $(STRIP) $(TARGET)-syms.efi -o $@ || { \
+               LANG=C strip $(TARGET)-syms.efi -o $@ 2>&1 | grep -q \
+               "relocation count is negative" && mv -f $(TARGET)-syms.efi $@; }
 ifneq ($(CONFIG_DEBUG_INFO),y)
        rm -f $(TARGET)-syms.efi
 endif

It will fall back to not stripping in case that bug is detected. I
don't know how to test it.
(the LANG=C is to always force the English message).

> ~Andrew

Frediano
Re: [PATCH v8] xen: Strip xen.efi by default
Posted by Marek Marczykowski-Górecki 5 days, 5 hours ago
On Thu, Nov 13, 2025 at 03:43:58PM +0000, Frediano Ziglio wrote:
> 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.

You meant xen-syms here, right?

> 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>

With the above fixed:

Reviewed-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>

-- 
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
Re: [PATCH for-4.21 v8] xen: Strip xen.efi by default
Posted by Andrew Cooper 5 days, 5 hours ago
On 13/11/2025 6:35 pm, Marek Marczykowski-Górecki wrote:
> On Thu, Nov 13, 2025 at 03:43:58PM +0000, Frediano Ziglio wrote:
>> 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.
> You meant xen-syms here, right?

I think so.  I just noticed the same.

>
>> 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>
> With the above fixed:
>
> Reviewed-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
>

I've done some ad-hoc testing and everything seems to be in order.

Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

Re: [PATCH for-4.21 v8] xen: Strip xen.efi by default
Posted by Frediano Ziglio 5 days ago
On Thu, 13 Nov 2025 at 18:40, Andrew Cooper <andrew.cooper3@citrix.com> wrote:
>
> On 13/11/2025 6:35 pm, Marek Marczykowski-Górecki wrote:
> > On Thu, Nov 13, 2025 at 03:43:58PM +0000, Frediano Ziglio wrote:
> >> 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.
> > You meant xen-syms here, right?
>
> I think so.  I just noticed the same.
>

Yes, my mistake

> >
> >> 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>
> > With the above fixed:
> >
> > Reviewed-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
> >
>
> I've done some ad-hoc testing and everything seems to be in order.
>
> Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

Thanks,
   Frediano