[PATCH 4.9 21/59] crypto, x86: aesni - fix token pasting for clang

From: Greg Kroah-Hartman
Date: Wed Nov 21 2018 - 14:10:19 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Michael Davidson <md@xxxxxxxxxx>

commit fdb2726f4e61c5e3abc052f547d5a5f6c0dc5504 upstream.

aes_ctrby8_avx-x86_64.S uses the C preprocessor for token pasting
of character sequences that are not valid preprocessor tokens.
While this is allowed when preprocessing assembler files it exposes
an incompatibilty between the clang and gcc preprocessors where
clang does not strip leading white space from macro parameters,
leading to the CONCAT(%xmm, i) macro expansion on line 96 resulting
in a token with a space character embedded in it.

While this could be resolved by deleting the offending space character,
the assembler is perfectly capable of doing the token pasting correctly
for itself so we can just get rid of the preprocessor macros.

Signed-off-by: Michael Davidson <md@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/crypto/aes_ctrby8_avx-x86_64.S | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

--- a/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
+++ b/arch/x86/crypto/aes_ctrby8_avx-x86_64.S
@@ -65,7 +65,6 @@
#include <linux/linkage.h>
#include <asm/inst.h>

-#define CONCAT(a,b) a##b
#define VMOVDQ vmovdqu

#define xdata0 %xmm0
@@ -92,8 +91,6 @@
#define num_bytes %r8

#define tmp %r10
-#define DDQ(i) CONCAT(ddq_add_,i)
-#define XMM(i) CONCAT(%xmm, i)
#define DDQ_DATA 0
#define XDATA 1
#define KEY_128 1
@@ -131,12 +128,12 @@ ddq_add_8:
/* generate a unique variable for ddq_add_x */

.macro setddq n
- var_ddq_add = DDQ(\n)
+ var_ddq_add = ddq_add_\n
.endm

/* generate a unique variable for xmm register */
.macro setxdata n
- var_xdata = XMM(\n)
+ var_xdata = %xmm\n
.endm

/* club the numeric 'id' to the symbol 'name' */