openwrtv4/target/linux/generic/hack-4.9/221-module_exports.patch
John Crispin 74d00a8c38 kernel: split patches folder up into backport, pending and hack folders
* properly format/comment all patches
* merge debloat patches
* merge Kconfig patches
* merge swconfig patches
* merge hotplug patches
* drop 200-fix_localversion.patch - upstream
* drop 222-arm_zimage_none.patch - unused
* drop 252-mv_cesa_depends.patch - no longer required
* drop 410-mtd-move-forward-declaration-of-struct-mtd_info.patch - unused
* drop 661-fq_codel_keep_dropped_stats.patch - outdated
* drop 702-phy_add_aneg_done_function.patch - upstream
* drop 840-rtc7301.patch - unused
* drop 841-rtc_pt7c4338.patch - upstream
* drop 921-use_preinit_as_init.patch - unused
* drop spio-gpio-old and gpio-mmc - unused

Signed-off-by: John Crispin <john@phrozen.org>
2017-08-05 08:46:36 +02:00

110 lines
3.6 KiB
Diff

From b14784e7883390c20ed3ff904892255404a5914b Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Fri, 7 Jul 2017 17:05:53 +0200
Subject: add an optional config option for stripping all unnecessary symbol exports from the kernel image
lede-commit: bb5a40c64b7c4f4848509fa0a6625055fc9e66cc
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
include/asm-generic/vmlinux.lds.h | 18 +++++++++++++++---
include/linux/export.h | 9 ++++++++-
scripts/Makefile.build | 2 +-
3 files changed, 24 insertions(+), 5 deletions(-)
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 83784d9492b1..189b5c7a0758 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -54,6 +54,16 @@
#define LOAD_OFFSET 0
#endif
+#ifndef SYMTAB_KEEP
+#define SYMTAB_KEEP KEEP(*(SORT(___ksymtab+*)))
+#define SYMTAB_KEEP_GPL KEEP(*(SORT(___ksymtab_gpl+*)))
+#endif
+
+#ifndef SYMTAB_DISCARD
+#define SYMTAB_DISCARD
+#define SYMTAB_DISCARD_GPL
+#endif
+
#include <linux/export.h>
/* Align . to a 8 byte boundary equals to maximum function alignment. */
@@ -329,14 +339,14 @@
/* Kernel symbol table: Normal symbols */ \
__ksymtab : AT(ADDR(__ksymtab) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ksymtab) = .; \
- KEEP(*(SORT(___ksymtab+*))) \
+ SYMTAB_KEEP \
VMLINUX_SYMBOL(__stop___ksymtab) = .; \
} \
\
/* Kernel symbol table: GPL-only symbols */ \
__ksymtab_gpl : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) { \
VMLINUX_SYMBOL(__start___ksymtab_gpl) = .; \
- KEEP(*(SORT(___ksymtab_gpl+*))) \
+ SYMTAB_KEEP_GPL \
VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .; \
} \
\
@@ -398,7 +408,7 @@
\
/* Kernel symbol table: strings */ \
__ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
- *(__ksymtab_strings) \
+ *(__ksymtab_strings+*) \
} \
\
/* __*init sections */ \
@@ -749,6 +759,8 @@
EXIT_TEXT \
EXIT_DATA \
EXIT_CALL \
+ SYMTAB_DISCARD \
+ SYMTAB_DISCARD_GPL \
*(.discard) \
*(.discard.*) \
}
diff --git a/include/linux/export.h b/include/linux/export.h
index 2a0f61fbc731..889331d9643d 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -53,12 +53,19 @@ extern struct module __this_module;
#define __CRC_SYMBOL(sym, sec)
#endif
+#ifdef MODULE
+#define __EXPORT_SUFFIX(sym)
+#else
+#define __EXPORT_SUFFIX(sym) "+" #sym
+#endif
+
/* For every exported symbol, place a struct in the __ksymtab section */
#define ___EXPORT_SYMBOL(sym, sec) \
extern typeof(sym) sym; \
__CRC_SYMBOL(sym, sec) \
static const char __kstrtab_##sym[] \
- __attribute__((section("__ksymtab_strings"), aligned(1))) \
+ __attribute__((section("__ksymtab_strings" \
+ __EXPORT_SUFFIX(sym)), aligned(1))) \
= VMLINUX_SYMBOL_STR(sym); \
static const struct kernel_symbol __ksymtab_##sym \
__used \
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 108d73273788..76a0e450123c 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -398,7 +398,7 @@ targets += $(extra-y) $(MAKECMDGOALS) $(always)
# Linker scripts preprocessor (.lds.S -> .lds)
# ---------------------------------------------------------------------------
quiet_cmd_cpp_lds_S = LDS $@
- cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
+ cmd_cpp_lds_S = $(CPP) $(EXTRA_LDSFLAGS) $(cpp_flags) -P -C -U$(ARCH) \
-D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
$(obj)/%.lds: $(src)/%.lds.S FORCE
--
2.11.0