arm: 1M align init, text, rodata if CONFIG_STRICT_MEMORY_RWX is set

Init code, text, rodata and data need different permissions
and so they need to be on different pages. The kernel 1-to-1
mapping is constructed using 1M pages to improve TLB performance
and this should not be changed (to 4K pages). Therefore
ensure that each of these regions starts on a 1M boundary.

Change-Id: I855b58d3deff6c34e58d1cbdef4b360c2b23ca6d
Signed-off-by: Larry Bassel <lbassel@codeaurora.org>
Signed-off-by: Jin Hong <jinh@codeaurora.org>
(cherry picked from commit 4cfee820adbdd7514b67e59c1b87008436d984ab)

arch/arm/kernel/vmlinux.lds.S

@@ -8,7 +8,10 @@
 #include <asm/thread_info.h>
 #include <asm/memory.h>
 #include <asm/page.h>
-	
+#ifdef CONFIG_STRICT_MEMORY_RWX
+#include <asm/pgtable.h>
+#endif
+
 #define PROC_INFO							\
 	. = ALIGN(4);							\
 	VMLINUX_SYMBOL(__proc_info_begin) = .;				\
@@ -90,6 +93,7 @@ SECTIONS
 		_text = .;
 		HEAD_TEXT
 	}
+
 	.text : {			/* Real text segment		*/
 		_stext = .;		/* Text and read-only data	*/
 			__exception_text_start = .;
@@ -111,6 +115,9 @@ SECTIONS
 		*(.got)			/* Global offset table		*/
 			ARM_CPU_KEEP(PROC_INFO)
 	}
+#ifdef CONFIG_STRICT_MEMORY_RWX
+	. = ALIGN(1<<SECTION_SHIFT);
+#endif
 
 	RO_DATA(PAGE_SIZE)
 
@@ -134,7 +141,11 @@ SECTIONS
 	_etext = .;			/* End of text and rodata section */
 
 #ifndef CONFIG_XIP_KERNEL
+#ifdef CONFIG_STRICT_MEMORY_RWX
+	. = ALIGN(1<<SECTION_SHIFT);
+#else
 	. = ALIGN(PAGE_SIZE);
+#endif
 	__init_begin = .;
 #endif
 
@@ -178,6 +189,10 @@ SECTIONS
 		INIT_RAM_FS
 	}
 #ifndef CONFIG_XIP_KERNEL
+#ifdef CONFIG_STRICT_MEMORY_RWX
+	. = ALIGN(1<<SECTION_SHIFT);
+#endif
+	__init_data = .;
 	.exit.data : {
 		ARM_EXIT_KEEP(EXIT_DATA)
 	}