Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fix

* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fix:
  mm/slab: fix section mismatch warning
  mm: fix section mismatch warnings
  init/main: use __init_refok to fix section mismatch
  kbuild: introduce __init_refok/__initdata_refok to supress section mismatch warnings
  all-archs: consolidate .data section definition in asm-generic
  all-archs: consolidate .text section definition in asm-generic
  kbuild: add "Section mismatch" warning whitelist for powerpc
  kbuild: make better section mismatch reports on i386, arm and mips
  kbuild: make modpost section warnings clearer
  kconfig: search harder for curses library in check-lxdialog.sh
  kbuild: include limits.h in sumversion.c for PATH_MAX
  powerpc: Fix the MODALIAS generation in modpost for of devices

include/linux/init.h

@@ -45,6 +45,19 @@
 #define __exitdata	__attribute__ ((__section__(".exit.data")))
 #define __exit_call	__attribute_used__ __attribute__ ((__section__ (".exitcall.exit")))
 
+/* modpost check for section mismatches during the kernel build.
+ * A section mismatch happens when there are references from a
+ * code or data section to an init section (both code or data).
+ * The init sections are (for most archs) discarded by the kernel
+ * when early init has completed so all such references are potential bugs.
+ * For exit sections the same issue exists.
+ * The following markers are used for the cases where the reference to
+ * the init/exit section (code or data) is valid and will teach modpost
+ * not to issue a warning.
+ * The markers follow same syntax rules as __init / __initdata. */
+#define __init_refok     noinline __attribute__ ((__section__ (".text.init.refok")))
+#define __initdata_refok          __attribute__ ((__section__ (".data.init.refok")))
+
 #ifdef MODULE
 #define __exit		__attribute__ ((__section__(".exit.text")))
 #else