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

[Frediano Ziglio <freddy77@xxxxxxxxx>]

On Fri, 14 Nov 2025 at 19:18, Andrew Cooper <andrew.cooper3@xxxxxxxxxx> 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@xxxxxxxxx>
> >>
> >> 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@xxxxxxxxx>
> > Release-Acked-By: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> >
> > 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