Disable the __builtin_return_address() warning globally after all

commit ef6000b4c6706cbb1787836442b5a74542b1809f upstream.

This affectively reverts commit 377ccbb48373 ("Makefile: Mute warning
for __builtin_return_address(>0) for tracing only") because it turns out
that it really isn't tracing only - it's all over the tree.

We already also had the warning disabled separately for mm/usercopy.c
(which this commit also removes), and it turns out that we will also
want to disable it for get_lock_parent_ip(), that is used for at least
TRACE_IRQFLAGS.  Which (when enabled) ends up being all over the tree.

Steven Rostedt had a patch that tried to limit it to just the config
options that actually triggered this, but quite frankly, the extra
complexity and abstraction just isn't worth it.  We have never actually
had a case where the warning is actually useful, so let's just disable
it globally and not worry about it.

Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Makefile b/Makefile
index 7cf2b498570331b8a42529c988ad99b024263e40..89ef9a890d9bced523cef797dbc8e48d16fbff5d 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -621,6 +621,7 @@ include arch/$(SRCARCH)/Makefile
 
 KBUILD_CFLAGS  += $(call cc-option,-fno-delete-null-pointer-checks,)
 KBUILD_CFLAGS  += $(call cc-disable-warning,maybe-uninitialized,)
+KBUILD_CFLAGS  += $(call cc-disable-warning,frame-address,)
 
 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
 KBUILD_CFLAGS  += -Os

diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index d0a1617b52b48d88ae2620713df2d80c2c3d85de..979e7bfbde7a840dd89fa1c0b2b17a9a0021d076 100644 (file)
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -1,8 +1,4 @@
 
-# We are fully aware of the dangers of __builtin_return_address()
-FRAME_CFLAGS := $(call cc-disable-warning,frame-address)
-KBUILD_CFLAGS += $(FRAME_CFLAGS)
-
 # Do not instrument the tracer itself:
 
 ifdef CONFIG_FUNCTION_TRACER

diff --git a/mm/Makefile b/mm/Makefile
index 2ca1faf3fa09038feaeea4fb4adbe5ea6717df30..295bd7a9f76bbb292d68f088546dc220231458d4 100644 (file)
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -21,9 +21,6 @@ KCOV_INSTRUMENT_memcontrol.o := n
 KCOV_INSTRUMENT_mmzone.o := n
 KCOV_INSTRUMENT_vmstat.o := n
 
-# Since __builtin_frame_address does work as used, disable the warning.
-CFLAGS_usercopy.o += $(call cc-disable-warning, frame-address)
-
 mmu-y                  := nommu.o
 mmu-$(CONFIG_MMU)      := gup.o highmem.o memory.o mincore.o \
                           mlock.o mmap.o mprotect.o mremap.o msync.o rmap.o \