[llvmlinux] [PATCH v3.10] ftrace: x86: Revert parts of 0033 patch from llvmlinux

Sedat Dilek sedat.dilek at gmail.com
Thu Jul 25 13:05:22 UTC 2013

Background: The build on x86_64 breaks with tracing support enabled.

pageexec from PaX Team suggested to drop the changes in 0033.
The result is tracing-support builds fine, now.
Also, I could boot into the generated kernel.

For more details see this thread on llvmlinux ML:
"[arch/x86/kernel/head64.c] In function `early_make_pgtable': undefined reference to `mcount'"

See also original patch from [1].

[1] http://git.linuxfoundation.org/?p=llvmlinux.git;a=blob;f=arch/x86_64/patches/0033-Various-fixes-in-arch-x86-include-asm.patch

Tested with pre-built toolchain v3.3 (AMD64) from <llvm.org> against Linux v3.10.

[ Untested: Doing some real tracing on x86_64. ]

Suggested-by: PaX Team <pageexec at gmail.com>
Signed-off-by: Sedat Dilek <sedat.dilek at gmail.com>
 arch/x86/include/asm/ftrace.h | 11 -----------
 1 file changed, 11 deletions(-)

diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h
index ca98134..0525a8b 100644
--- a/arch/x86/include/asm/ftrace.h
+++ b/arch/x86/include/asm/ftrace.h
@@ -32,17 +32,6 @@
 	addq $(SS+8-\skip), %rsp
-#define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
-#define CALLER_ADDR1 0UL
-#define CALLER_ADDR2 0UL
-#define CALLER_ADDR3 0UL
-#define CALLER_ADDR4 0UL
-#define CALLER_ADDR5 0UL
-#define CALLER_ADDR6 0UL

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