allow stripping of generated symbols under CONFIG_KALLSYMS_ALL

Building upon parts of the module stripping patch, this patch
introduces similar stripping for vmlinux when CONFIG_KALLSYMS_ALL=y.
Using CONFIG_KALLSYMS_STRIP_GENERATED reduces the overhead of
CONFIG_KALLSYMS_ALL from 245k/310k to 65k/80k for the (i386/x86-64)
kernels I tested with.

The patch also does away with the need to special case the kallsyms-
internal symbols by making them available even in the first linking
stage.

While it is a generated file, the patch includes the changes to
scripts/genksyms/keywords.c_shipped, as I'm unsure what the procedure
here is.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

1 files changed, 6 insertions, 10 deletions

diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 7b8b0f21a5b1..e694afa0eb8c 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -30,20 +30,19 @@
 #define all_var 0
 #endif
 
-/* These will be re-linked against their real values during the second link stage */
-extern const unsigned long kallsyms_addresses[] __attribute__((weak));
-extern const u8 kallsyms_names[] __attribute__((weak));
+extern const unsigned long kallsyms_addresses[];
+extern const u8 kallsyms_names[];
 
 /* tell the compiler that the count isn't in the small data section if the arch
  * has one (eg: FRV)
  */
 extern const unsigned long kallsyms_num_syms
-__attribute__((weak, section(".rodata")));
+        __attribute__((__section__(".rodata")));
 
-extern const u8 kallsyms_token_table[] __attribute__((weak));
-extern const u16 kallsyms_token_index[] __attribute__((weak));
+extern const u8 kallsyms_token_table[];
+extern const u16 kallsyms_token_index[];
 
-extern const unsigned long kallsyms_markers[] __attribute__((weak));
+extern const unsigned long kallsyms_markers[];
 
 static inline int is_kernel_inittext(unsigned long addr)
 {
@@ -168,9 +167,6 @@ static unsigned long get_symbol_pos(unsigned long addr,
         unsigned long symbol_start = 0, symbol_end = 0;
         unsigned long i, low, high, mid;
 
-        /* This kernel should never had been booted. */
-        BUG_ON(!kallsyms_addresses);
-
         /* do a binary search on the sorted kallsyms_addresses array */
         low = 0;
         high = kallsyms_num_syms;