The GOT is changed during early boot when relocations are applied. Make
it read-only directly. This table exists only for PIE binary.

Position Independent Executable (PIE) support will allow to extended the
KASLR randomization range below the -2G memory limit.

Signed-off-by: Thomas Garnier <thgar...@google.com>
---
 include/asm-generic/vmlinux.lds.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/asm-generic/vmlinux.lds.h 
b/include/asm-generic/vmlinux.lds.h
index 1ab0e520d6fc..89398d042f78 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -295,6 +295,17 @@
        VMLINUX_SYMBOL(__end_ro_after_init) = .;
 #endif
 
+#ifdef CONFIG_X86_PIE
+#define RO_GOT_X86                                                     \
+       .got        : AT(ADDR(.got) - LOAD_OFFSET) {                    \
+               VMLINUX_SYMBOL(__start_got) = .;                        \
+               *(.got);                                                \
+               VMLINUX_SYMBOL(__end_got) = .;                          \
+       }
+#else
+#define RO_GOT_X86
+#endif
+
 /*
  * Read only Data
  */
@@ -351,6 +362,7 @@
                VMLINUX_SYMBOL(__end_builtin_fw) = .;                   \
        }                                                               \
                                                                        \
+       RO_GOT_X86                                                      \
        TRACEDATA                                                       \
                                                                        \
        /* Kernel symbol table: Normal symbols */                       \
-- 
2.16.2.660.g709887971b-goog

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