Merge branch 'akpm' (patchbomb from Andrew Morton)

Merge incoming from Andrew Morton:
 - Various misc things.
 - arch/sh updates.
 - Part of ocfs2.  Review is slow.
 - Slab updates.
 - Most of -mm.
 - printk updates.
 - lib/ updates.
 - checkpatch updates.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (226 commits)
  checkpatch: update $declaration_macros, add uninitialized_var
  checkpatch: warn on missing spaces in broken up quoted
  checkpatch: fix false positives for --strict "space after cast" test
  checkpatch: fix false positive MISSING_BREAK warnings with --file
  checkpatch: add test for native c90 types in unusual order
  checkpatch: add signed generic types
  checkpatch: add short int to c variable types
  checkpatch: add for_each tests to indentation and brace tests
  checkpatch: fix brace style misuses of else and while
  checkpatch: add --fix option for a couple OPEN_BRACE misuses
  checkpatch: use the correct indentation for which()
  checkpatch: add fix_insert_line and fix_delete_line helpers
  checkpatch: add ability to insert and delete lines to patch/file
  checkpatch: add an index variable for fixed lines
  checkpatch: warn on break after goto or return with same tab indentation
  checkpatch: emit a warning on file add/move/delete
  checkpatch: add test for commit id formatting style in commit log
  checkpatch: emit fewer kmalloc_array/kcalloc conversion warnings
  checkpatch: improve "no space after cast" test
  checkpatch: allow multiple const * types
  ...

1 files changed, 19 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index d0901b46b4bf..a897c50db515 100644
--- a/Makefile
+++ b/Makefile
@@ -621,6 +621,9 @@ else
 KBUILD_CFLAGS   += -O2
 endif
 
+# Tell gcc to never replace conditional load with a non-conditional one
+KBUILD_CFLAGS   += $(call cc-option,--param=allow-store-data-races=0)
+
 ifdef CONFIG_READABLE_ASM
 # Disable optimizations that make assembler listings hard to read.
 # reorder blocks reorders the control in the function
@@ -636,6 +639,22 @@ KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN})
 endif
 
 # Handle stack protector mode.
+#
+# Since kbuild can potentially perform two passes (first with the old
+# .config values and then with updated .config values), we cannot error out
+# if a desired compiler option is unsupported. If we were to error, kbuild
+# could never get to the second pass and actually notice that we changed
+# the option to something that was supported.
+#
+# Additionally, we don't want to fallback and/or silently change which compiler
+# flags will be used, since that leads to producing kernels with different
+# security feature characteristics depending on the compiler used. ("But I
+# selected CC_STACKPROTECTOR_STRONG! Why did it build with _REGULAR?!")
+#
+# The middle ground is to warn here so that the failed option is obvious, but
+# to let the build fail with bad compiler flags so that we can't produce a
+# kernel when there is a CONFIG and compiler mismatch.
+#
 ifdef CONFIG_CC_STACKPROTECTOR_REGULAR
   stackp-flag := -fstack-protector
   ifeq ($(call cc-option, $(stackp-flag)),)