On Mon, Sep 15, 2025 at 07:56:16AM +0200, Nicolas Schier wrote:

On Mon, Aug 18, 2025 at 06:54:57PM +0200, Alexey Gladkov wrote:

quoted

From: Masahiro Yamada <masahiroy@kernel.org>

Keep the .modinfo section during linking, but strip it from the final
vmlinux.

Adjust scripts/mksysmap to exclude modinfo symbols from kallsyms.

This change will allow the next commit to extract the .modinfo section
from the vmlinux.unstripped intermediate.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
 include/asm-generic/vmlinux.lds.h | 2 +-
 scripts/Makefile.vmlinux          | 2 +-
 scripts/mksysmap                  | 3 +++
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index ae2d2359b79e9..cfa63860dfd4c 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h

@@ -831,6 +831,7 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG)
 
 /* Required sections not related to debugging. */
 #define ELF_DETAILS							\
+		.modinfo : { *(.modinfo) }				\
 		.comment 0 : { *(.comment) }				\
 		.symtab 0 : { *(.symtab) }				\
 		.strtab 0 : { *(.strtab) }				\

@@ -1044,7 +1045,6 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG)
 	*(.discard.*)							\
 	*(.export_symbol)						\
 	*(.no_trim_symbol)						\
-	*(.modinfo)							\
 	/* ld.bfd warns about .gnu.version* even when not emitted */	\
 	*(.gnu.version*)						\
 

diff --git a/scripts/Makefile.vmlinux b/scripts/Makefile.vmlinux
index 4f2d4c3fb7372..e2ceeb9e168d4 100644
--- a/scripts/Makefile.vmlinux
+++ b/scripts/Makefile.vmlinux

@@ -86,7 +86,7 @@ endif
 # vmlinux
 # ---------------------------------------------------------------------------
 
-remove-section-y                                   :=
+remove-section-y                                   := .modinfo
 remove-section-$(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS) += '.rel*'
 
 quiet_cmd_strip_relocs = OBJCOPY $@

diff --git a/scripts/mksysmap b/scripts/mksysmap
index 3accbdb269ac7..a607a0059d119 100755
--- a/scripts/mksysmap
+++ b/scripts/mksysmap

@@ -79,6 +79,9 @@
 / _SDA_BASE_$/d
 / _SDA2_BASE_$/d
 
+# MODULE_INFO()
+/ __UNIQUE_ID_modinfo[0-9]*$/d
+
 # ---------------------------------------------------------------------------
 # Ignored patterns
 #  (symbols that contain the pattern are ignored)

-- 
2.50.1

Hi Alexey,

with this patch applied, I still get a warning from objcpy as Masahiro
and Stephen wrote [1,2]

  SORTTAB vmlinux.unstripped
+ sorttable vmlinux.unstripped
+ nm -S vmlinux.unstripped
+ ./scripts/sorttable -s .tmp_vmlinux.nm-sort vmlinux.unstripped
+ is_enabled CONFIG_KALLSYMS
+ grep -q ^CONFIG_KALLSYMS=y include/config/auto.conf
+ cmp -s System.map .tmp_vmlinux2.syms
+ echo vmlinux.unstripped: ../scripts/link-vmlinux.sh
# OBJCOPY vmlinux
  objcopy --remove-section=.modinfo vmlinux.unstripped vmlinux
objcopy: vmlinux.unstripped: warning: empty loadable segment detected at vaddr=0xffff8000807a0000, is this intentional?

(arm64, allnoconfig)

Kind regards,
Nicolas


[1]: https://lore.kernel.org/linux-kbuild/CAK7LNAR-gD2H6Kk-rZjo0R3weTHCGTm0a=u2tRH1WWW6Sx6=RQ@mail.gmail.com/ (local)
[2]: https://lore.kernel.org/lkml/20250730164047.7c4a731a@canb.auug.org.au/ (local)

Hm. I missed that. I need to investigate how to fix this. Nothing comes
to mind right now.

-- 
Rgrds, legion