[PATCH] x86: fix CFI macro invocations to deal with shortcomings in gas

Jan Beulich
2010-10-19T13:52:26Z

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>
Cc: Alexander van Heukelum <heukelum@fastmail.fm>

---
Kbuild | 2 -
arch/x86/include/asm/calling.h | 52 +++++++++++++++++++-------------------
arch/x86/include/asm/entry_arch.h | 19 ++-----------
arch/x86/include/asm/segment.h | 32 +++++++++++------------
arch/x86/kernel/asm-offsets_32.c | 4 --
arch/x86/kernel/entry_32.S | 6 ++--
arch/x86/kernel/entry_64.S | 20 ++------------
7 files changed, 56 insertions(+), 79 deletions(-)

--- 2.6.36-rc8-x86-cfi.orig/Kbuild
+++ 2.6.36-rc8-x86-cfi/Kbuild
@@ -53,7 +53,7 @@ targets += arch/$(SRCARCH)/kernel/asm-of
# Default sed regexp - multiline due to syntax constraints
define sed-y
"/^->/{s:->#\(.*\):/* \1 */:; \
- s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
+ s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 (\2) /* \3 */:; \
s:->::; p;}"
endef

--- 2.6.36-rc8-x86-cfi.orig/arch/x86/include/asm/calling.h
+++ 2.6.36-rc8-x86-cfi/arch/x86/include/asm/calling.h
@@ -48,36 +48,38 @@ For 32-bit we have the following convent

/*
- * 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 convent
.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 convent
.endif
.endm

-#define REST_SKIP 6*8
+#define REST_SKIP (6*8)

.macro SAVE_REST
subq $REST_SKIP, %rsp
--- 2.6.36-rc8-x86-cfi.orig/arch/x86/include/asm/entry_arch.h
+++ 2.6.36-rc8-x86-cfi/arch/x86/include/asm/entry_arch.h
@@ -16,22 +16,11 @@ BUILD_INTERRUPT(call_function_single_int
BUILD_INTERRUPT(irq_move_cleanup_interrupt,IRQ_MOVE_CLEANUP_VECTOR)
BUILD_INTERRUPT(reboot_interrupt,REBOOT_VECTOR)

-BUILD_INTERRUPT3(invalidate_interrupt0,INVALIDATE_TLB_VECTOR_START+0,
- smp_invalidate_interrupt)
-BUILD_INTERRUPT3(invalidate_interrupt1,INVALIDATE_TLB_VECTOR_START+1,
- smp_invalidate_interrupt)
-BUILD_INTERRUPT3(invalidate_interrupt2,INVALIDATE_TLB_VECTOR_START+2,
- smp_invalidate_interrupt)
-BUILD_INTERRUPT3(invalidate_interrupt3,INVALIDATE_TLB_VECTOR_START+3,
- smp_invalidate_interrupt)
-BUILD_INTERRUPT3(invalidate_interrupt4,INVALIDATE_TLB_VECTOR_START+4,
- smp_invalidate_interrupt)
-BUILD_INTERRUPT3(invalidate_interrupt5,INVALIDATE_TLB_VECTOR_START+5,
- smp_invalidate_interrupt)
-BUILD_INTERRUPT3(invalidate_interrupt6,INVALIDATE_TLB_VECTOR_START+6,
- smp_invalidate_interrupt)
-BUILD_INTERRUPT3(invalidate_interrupt7,INVALIDATE_TLB_VECTOR_START+7,
+.irpc idx, "01234567"
+BUILD_INTERRUPT3(invalidate_interrupt\idx,
+ (INVALIDATE_TLB_VECTOR_START)+\idx,
smp_invalidate_interrupt)
+.endr
#endif

BUILD_INTERRUPT(x86_platform_ipi, X86_PLATFORM_IPI_VECTOR)
--- 2.6.36-rc8-x86-cfi.orig/arch/x86/include/asm/segment.h
+++ 2.6.36-rc8-x86-cfi/arch/x86/include/asm/segment.h
@@ -73,31 +73,31 @@

#define GDT_ENTRY_DEFAULT_USER_DS 15

-#define GDT_ENTRY_KERNEL_BASE 12
+#define GDT_ENTRY_KERNEL_BASE (12)

-#define GDT_ENTRY_KERNEL_CS (GDT_ENTRY_KERNEL_BASE + 0)
+#define GDT_ENTRY_KERNEL_CS (GDT_ENTRY_KERNEL_BASE+0)

-#define GDT_ENTRY_KERNEL_DS (GDT_ENTRY_KERNEL_BASE + 1)
+#define GDT_ENTRY_KERNEL_DS (GDT_ENTRY_KERNEL_BASE+1)

-#define GDT_ENTRY_TSS (GDT_ENTRY_KERNEL_BASE + 4)
-#define GDT_ENTRY_LDT (GDT_ENTRY_KERNEL_BASE + 5)
+#define GDT_ENTRY_TSS (GDT_ENTRY_KERNEL_BASE+4)
+#define GDT_ENTRY_LDT (GDT_ENTRY_KERNEL_BASE+5)

-#define GDT_ENTRY_PNPBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 6)
-#define GDT_ENTRY_APMBIOS_BASE (GDT_ENTRY_KERNEL_BASE + 11)
+#define GDT_ENTRY_PNPBIOS_BASE (GDT_ENTRY_KERNEL_BASE+6)
+#define GDT_ENTRY_APMBIOS_BASE (GDT_ENTRY_KERNEL_BASE+11)

-#define GDT_ENTRY_ESPFIX_SS (GDT_ENTRY_KERNEL_BASE + 14)
-#define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8)
+#define GDT_ENTRY_ESPFIX_SS (GDT_ENTRY_KERNEL_BASE+14)
+#define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS*8)

-#define GDT_ENTRY_PERCPU (GDT_ENTRY_KERNEL_BASE + 15)
+#define GDT_ENTRY_PERCPU (GDT_ENTRY_KERNEL_BASE+15)
#ifdef CONFIG_SMP
#define __KERNEL_PERCPU (GDT_ENTRY_PERCPU * 8)
#else
#define __KERNEL_PERCPU 0
#endif

-#define GDT_ENTRY_STACK_CANARY (GDT_ENTRY_KERNEL_BASE + 16)
+#define GDT_ENTRY_STACK_CANARY (GDT_ENTRY_KERNEL_BASE+16)
#ifdef CONFIG_CC_STACKPROTECTOR
-#define __KERNEL_STACK_CANARY (GDT_ENTRY_STACK_CANARY * 8)
+#define __KERNEL_STACK_CANARY (GDT_ENTRY_STACK_CANARY*8)
#else
#define __KERNEL_STACK_CANARY 0
#endif
@@ -182,10 +182,10 @@

#endif

-#define __KERNEL_CS (GDT_ENTRY_KERNEL_CS * 8)
-#define __KERNEL_DS (GDT_ENTRY_KERNEL_DS * 8)
-#define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS* 8 + 3)
-#define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS* 8 + 3)
+#define __KERNEL_CS (GDT_ENTRY_KERNEL_CS*8)
+#define __KERNEL_DS (GDT_ENTRY_KERNEL_DS*8)
+#define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS*8+3)
+#define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS*8+3)
#ifndef CONFIG_PARAVIRT
#define get_kernel_rpl() 0
#endif
--- 2.6.36-rc8-x86-cfi.orig/arch/x86/kernel/asm-offsets_32.c
+++ 2.6.36-rc8-x86-cfi/arch/x86/kernel/asm-offsets_32.c
@@ -99,9 +99,7 @@ void foo(void)

DEFINE(PAGE_SIZE_asm, PAGE_SIZE);
DEFINE(PAGE_SHIFT_asm, PAGE_SHIFT);
- DEFINE(PTRS_PER_PTE, PTRS_PER_PTE);
- DEFINE(PTRS_PER_PMD, PTRS_PER_PMD);
- DEFINE(PTRS_PER_PGD, PTRS_PER_PGD);
+ DEFINE(THREAD_SIZE_asm, THREAD_SIZE);

OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx);

--- 2.6.36-rc8-x86-cfi.orig/arch/x86/kernel/entry_32.S
+++ 2.6.36-rc8-x86-cfi/arch/x86/kernel/entry_32.S
@@ -382,20 +382,20 @@ sysenter_past_esp:
* enough kernel state to call TRACE_IRQS_OFF can be called - but
* we immediately enable interrupts at that point anyway.
*/
- pushl_cfi $(__USER_DS)
+ pushl_cfi $__USER_DS
/*CFI_REL_OFFSET ss, 0*/
pushl_cfi %ebp
CFI_REL_OFFSET esp, 0
pushfl_cfi
orl $X86_EFLAGS_IF, (%esp)
- pushl_cfi $(__USER_CS)
+ pushl_cfi $__USER_CS
/*CFI_REL_OFFSET cs, 0*/
/*
* Push current_thread_info()->sysenter_return to the stack.
* A tiny bit of offset fixup is necessary - 4*4 means the 4 words
* pushed above; +8 corresponds to copy_thread's esp0 setting.
*/
- pushl_cfi (TI_sysenter_return-THREAD_SIZE+8+4*4)(%esp)
+ pushl_cfi TI_sysenter_return-THREAD_SIZE_asm+8+4*4(%esp)
CFI_REL_OFFSET eip, 0

pushl_cfi %eax
--- 2.6.36-rc8-x86-cfi.orig/arch/x86/kernel/entry_64.S
+++ 2.6.36-rc8-x86-cfi/arch/x86/kernel/entry_64.S
@@ -964,22 +964,10 @@ apicinterrupt X86_PLATFORM_IPI_VECTOR \
x86_platform_ipi smp_x86_platform_ipi

#ifdef CONFIG_SMP
-apicinterrupt INVALIDATE_TLB_VECTOR_START+0 \
- invalidate_interrupt0 smp_invalidate_interrupt
-apicinterrupt INVALIDATE_TLB_VECTOR_START+1 \
- invalidate_interrupt1 smp_invalidate_interrupt
-apicinterrupt INVALIDATE_TLB_VECTOR_START+2 \
- invalidate_interrupt2 smp_invalidate_interrupt
-apicinterrupt INVALIDATE_TLB_VECTOR_START+3 \
- invalidate_interrupt3 smp_invalidate_interrupt
-apicinterrupt INVALIDATE_TLB_VECTOR_START+4 \
- invalidate_interrupt4 smp_invalidate_interrupt
-apicinterrupt INVALIDATE_TLB_VECTOR_START+5 \
- invalidate_interrupt5 smp_invalidate_interrupt
-apicinterrupt INVALIDATE_TLB_VECTOR_START+6 \
- invalidate_interrupt6 smp_invalidate_interrupt
-apicinterrupt INVALIDATE_TLB_VECTOR_START+7 \
- invalidate_interrupt7 smp_invalidate_interrupt
+.irpc idx, "01234567"
+apicinterrupt (INVALIDATE_TLB_VECTOR_START)+\idx \
+ invalidate_interrupt\idx smp_invalidate_interrupt
+.endr
#endif

apicinterrupt THRESHOLD_APIC_VECTOR \