x86, asm: Fix CFI macro invocations to deal with shortcomings in gas

gas prior to (perhaps) 2.16.90 has problems with passing non-
parenthesized expressions containing spaces to macros. Spaces, however,
get inserted by cpp between any macro expanding to a number and a
subsequent + or -. For the +, current x86 gas then removes the space
again (future gas may not do so), but for the - the space gets retained
and is then considered a separator between macro arguments.

Fix the respective definitions for both the - and + cases, so that they
neither contain spaces nor make cpp insert any (the latter by adding
seemingly redundant parentheses).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4CBDBEBA020000780001E05A@vpn.id2.novell.com>
Cc: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 27 insertions, 25 deletions

diff --git a/arch/x86/include/asm/calling.h b/arch/x86/include/asm/calling.h
index 0e63c9a2a8d0..30af5a832163 100644
--- a/arch/x86/include/asm/calling.h
+++ b/arch/x86/include/asm/calling.h
@@ -48,36 +48,38 @@ For 32-bit we have the following conventions - kernel is built with
 
 
 /*
- * 64-bit system call stack frame layout defines and helpers,
- * for assembly code:
+ * 64-bit system call stack frame layout defines and helpers, for
+ * assembly code (note that the seemingly unnecessary parentheses
+ * are to prevent cpp from inserting spaces in expressions that get
+ * passed to macros):
  */
 
-#define R15               0
-#define R14               8
-#define R13              16
-#define R12              24
-#define RBP              32
-#define RBX              40
+#define R15               (0)
+#define R14               (8)
+#define R13              (16)
+#define R12              (24)
+#define RBP              (32)
+#define RBX              (40)
 
 /* arguments: interrupts/non tracing syscalls only save up to here: */
-#define R11              48
-#define R10              56
-#define R9               64
-#define R8               72
-#define RAX              80
-#define RCX              88
-#define RDX              96
-#define RSI             104
-#define RDI             112
-#define ORIG_RAX        120       /* + error_code */
+#define R11              (48)
+#define R10              (56)
+#define R9               (64)
+#define R8               (72)
+#define RAX              (80)
+#define RCX              (88)
+#define RDX              (96)
+#define RSI             (104)
+#define RDI             (112)
+#define ORIG_RAX        (120)       /* + error_code */
 /* end of arguments */
 
 /* cpu exception frame or undefined in case of fast syscall: */
-#define RIP             128
-#define CS              136
-#define EFLAGS          144
-#define RSP             152
-#define SS              160
+#define RIP             (128)
+#define CS              (136)
+#define EFLAGS          (144)
+#define RSP             (152)
+#define SS              (160)
 
 #define ARGOFFSET       R11
 #define SWFRAME         ORIG_RAX
@@ -111,7 +113,7 @@ For 32-bit we have the following conventions - kernel is built with
         .endif
         .endm
 
-#define ARG_SKIP        9*8
+#define ARG_SKIP        (9*8)
 
         .macro RESTORE_ARGS skiprax=0, addskip=0, skiprcx=0, skipr11=0, \
                             skipr8910=0, skiprdx=0
@@ -169,7 +171,7 @@ For 32-bit we have the following conventions - kernel is built with
         .endif
         .endm
 
-#define REST_SKIP       6*8
+#define REST_SKIP       (6*8)
 
         .macro SAVE_REST
         subq $REST_SKIP, %rsp