[IA64] Add __mca_table to the DISCARD list in gate.lds

Add __mca_table to the DISCARD list for the gate.lds linker script to
avoid broken linker references when linking the final vmlinux file.

Also add comment to include/asm-ia64/asmmacros.h to avoid anyone else
hitting this problem in the future.

Credits to James Bottomley <James.Bottomley@SteelEye.com> for spotting
the DISCARD list in gate.lds.S

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

2 files changed, 5 insertions, 0 deletions

diff --git a/arch/ia64/kernel/gate.lds.S b/arch/ia64/kernel/gate.lds.S
index e1e4aba9ecd0..7c99e6ec3daf 100644
--- a/arch/ia64/kernel/gate.lds.S
+++ b/arch/ia64/kernel/gate.lds.S
@@ -59,6 +59,7 @@ SECTIONS
         *(.dynbss)
         *(.bss .bss.* .gnu.linkonce.b.*)
         *(__ex_table)
+        *(__mca_table)
   }
 }
 
diff --git a/include/asm-ia64/asmmacro.h b/include/asm-ia64/asmmacro.h
index d4cec32083d8..edf2cebb2969 100644
--- a/include/asm-ia64/asmmacro.h
+++ b/include/asm-ia64/asmmacro.h
@@ -38,6 +38,10 @@ name:
 
 /*
  * Helper macros for accessing user memory.
+ *
+ * When adding any new .section/.previous entries here, make sure to
+ * also add it to the DISCARD section in arch/ia64/kernel/gate.lds.S or
+ * unpleasant things will happen.
  */
 
         .section "__ex_table", "a"              // declare section & section attributes