kernel: update 4.9 to 4.9.47
[openwrt/openwrt.git] / target / linux / generic / hack-4.9 / 221-module_exports.patch
1 From b14784e7883390c20ed3ff904892255404a5914b Mon Sep 17 00:00:00 2001
2 From: Felix Fietkau <nbd@nbd.name>
3 Date: Fri, 7 Jul 2017 17:05:53 +0200
4 Subject: add an optional config option for stripping all unnecessary symbol exports from the kernel image
5
6 lede-commit: bb5a40c64b7c4f4848509fa0a6625055fc9e66cc
7 Signed-off-by: Felix Fietkau <nbd@nbd.name>
8 ---
9 include/asm-generic/vmlinux.lds.h | 18 +++++++++++++++---
10 include/linux/export.h | 9 ++++++++-
11 scripts/Makefile.build | 2 +-
12 3 files changed, 24 insertions(+), 5 deletions(-)
13
14 --- a/include/asm-generic/vmlinux.lds.h
15 +++ b/include/asm-generic/vmlinux.lds.h
16 @@ -54,6 +54,16 @@
17 #define LOAD_OFFSET 0
18 #endif
19
20 +#ifndef SYMTAB_KEEP
21 +#define SYMTAB_KEEP KEEP(*(SORT(___ksymtab+*)))
22 +#define SYMTAB_KEEP_GPL KEEP(*(SORT(___ksymtab_gpl+*)))
23 +#endif
24 +
25 +#ifndef SYMTAB_DISCARD
26 +#define SYMTAB_DISCARD
27 +#define SYMTAB_DISCARD_GPL
28 +#endif
29 +
30 #include <linux/export.h>
31
32 /* Align . to a 8 byte boundary equals to maximum function alignment. */
33 @@ -342,14 +352,14 @@
34 /* Kernel symbol table: Normal symbols */ \
35 __ksymtab : AT(ADDR(__ksymtab) - LOAD_OFFSET) { \
36 VMLINUX_SYMBOL(__start___ksymtab) = .; \
37 - KEEP(*(SORT(___ksymtab+*))) \
38 + SYMTAB_KEEP \
39 VMLINUX_SYMBOL(__stop___ksymtab) = .; \
40 } \
41 \
42 /* Kernel symbol table: GPL-only symbols */ \
43 __ksymtab_gpl : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) { \
44 VMLINUX_SYMBOL(__start___ksymtab_gpl) = .; \
45 - KEEP(*(SORT(___ksymtab_gpl+*))) \
46 + SYMTAB_KEEP_GPL \
47 VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .; \
48 } \
49 \
50 @@ -411,7 +421,7 @@
51 \
52 /* Kernel symbol table: strings */ \
53 __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
54 - *(__ksymtab_strings) \
55 + *(__ksymtab_strings+*) \
56 } \
57 \
58 /* __*init sections */ \
59 @@ -763,6 +773,8 @@
60 EXIT_TEXT \
61 EXIT_DATA \
62 EXIT_CALL \
63 + SYMTAB_DISCARD \
64 + SYMTAB_DISCARD_GPL \
65 *(.discard) \
66 *(.discard.*) \
67 }
68 --- a/include/linux/export.h
69 +++ b/include/linux/export.h
70 @@ -53,12 +53,19 @@ extern struct module __this_module;
71 #define __CRC_SYMBOL(sym, sec)
72 #endif
73
74 +#ifdef MODULE
75 +#define __EXPORT_SUFFIX(sym)
76 +#else
77 +#define __EXPORT_SUFFIX(sym) "+" #sym
78 +#endif
79 +
80 /* For every exported symbol, place a struct in the __ksymtab section */
81 #define ___EXPORT_SYMBOL(sym, sec) \
82 extern typeof(sym) sym; \
83 __CRC_SYMBOL(sym, sec) \
84 static const char __kstrtab_##sym[] \
85 - __attribute__((section("__ksymtab_strings"), aligned(1))) \
86 + __attribute__((section("__ksymtab_strings" \
87 + __EXPORT_SUFFIX(sym)), aligned(1))) \
88 = VMLINUX_SYMBOL_STR(sym); \
89 static const struct kernel_symbol __ksymtab_##sym \
90 __used \
91 --- a/scripts/Makefile.build
92 +++ b/scripts/Makefile.build
93 @@ -398,7 +398,7 @@ targets += $(extra-y) $(MAKECMDGOALS) $(
94 # Linker scripts preprocessor (.lds.S -> .lds)
95 # ---------------------------------------------------------------------------
96 quiet_cmd_cpp_lds_S = LDS $@
97 - cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
98 + cmd_cpp_lds_S = $(CPP) $(EXTRA_LDSFLAGS) $(cpp_flags) -P -C -U$(ARCH) \
99 -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
100
101 $(obj)/%.lds: $(src)/%.lds.S FORCE