[ARM] 5383/2: unwind: Add core support for ARM stack unwinding

This patch adds the main functionality for parsing the stack unwinding
information generated by the ARM EABI toolchains. The unwinding
information consists of an index with a pair of words per function and a
table with unwinding instructions. For more information, see "Exception
Handling ABI for the ARM Architecture" at:

http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 19 insertions, 0 deletions

diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 00216071eaf7..5f664599c945 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -80,6 +80,8 @@ SECTIONS
                 EXIT_TEXT
                 EXIT_DATA
                 *(.exitcall.exit)
+                *(.ARM.exidx.exit.text)
+                *(.ARM.extab.exit.text)
 #ifndef CONFIG_MMU
                 *(.fixup)
                 *(__ex_table)
@@ -110,6 +112,23 @@ SECTIONS
 
         _etext = .;                     /* End of text and rodata section */
 
+#ifdef CONFIG_ARM_UNWIND
+        /*
+         * Stack unwinding tables
+         */
+        . = ALIGN(8);
+        .ARM.unwind_idx : {
+                __start_unwind_idx = .;
+                *(.ARM.exidx*)
+                __stop_unwind_idx = .;
+        }
+        .ARM.unwind_tab : {
+                __start_unwind_tab = .;
+                *(.ARM.extab*)
+                __stop_unwind_tab = .;
+        }
+#endif
+
 #ifdef CONFIG_XIP_KERNEL
         __data_loc = ALIGN(4);          /* location in binary */
         . = PAGE_OFFSET + TEXT_OFFSET;