ARM: 7171/1: unwind: add unwind directives to bitops assembly macros
The bitops functions (e.g. _test_and_set_bit) on ARM do not have unwind
annotations and therefore the kernel cannot backtrace out of them on a
fatal error (for example, NULL pointer dereference).
This patch annotates the bitops assembly macros with UNWIND annotations
so that we can produce a meaningful backtrace on error. Callers of the
macros are modified to pass their function name as a macro parameter,
enforcing that the macros are used as standalone function implementations.
Acked-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/lib/bitops.h b/arch/arm/lib/bitops.h
index 10d868a..d6408d1 100644
--- a/arch/arm/lib/bitops.h
+++ b/arch/arm/lib/bitops.h
@@ -1,5 +1,9 @@
+#include <asm/unwind.h>
+
#if __LINUX_ARM_ARCH__ >= 6
- .macro bitop, instr
+ .macro bitop, name, instr
+ENTRY( \name )
+UNWIND( .fnstart )
ands ip, r1, #3
strneb r1, [ip] @ assert word-aligned
mov r2, #1
@@ -13,9 +17,13 @@
cmp r0, #0
bne 1b
bx lr
+UNWIND( .fnend )
+ENDPROC(\name )
.endm
- .macro testop, instr, store
+ .macro testop, name, instr, store
+ENTRY( \name )
+UNWIND( .fnstart )
ands ip, r1, #3
strneb r1, [ip] @ assert word-aligned
mov r2, #1
@@ -34,9 +42,13 @@
cmp r0, #0
movne r0, #1
2: bx lr
+UNWIND( .fnend )
+ENDPROC(\name )
.endm
#else
- .macro bitop, instr
+ .macro bitop, name, instr
+ENTRY( \name )
+UNWIND( .fnstart )
ands ip, r1, #3
strneb r1, [ip] @ assert word-aligned
and r2, r0, #31
@@ -49,6 +61,8 @@
str r2, [r1, r0, lsl #2]
restore_irqs ip
mov pc, lr
+UNWIND( .fnend )
+ENDPROC(\name )
.endm
/**
@@ -59,7 +73,9 @@
* Note: we can trivially conditionalise the store instruction
* to avoid dirtying the data cache.
*/
- .macro testop, instr, store
+ .macro testop, name, instr, store
+ENTRY( \name )
+UNWIND( .fnstart )
ands ip, r1, #3
strneb r1, [ip] @ assert word-aligned
and r3, r0, #31
@@ -73,5 +89,7 @@
moveq r0, #0
restore_irqs ip
mov pc, lr
+UNWIND( .fnend )
+ENDPROC(\name )
.endm
#endif
diff --git a/arch/arm/lib/changebit.S b/arch/arm/lib/changebit.S
index 68ed5b6..f402786 100644
--- a/arch/arm/lib/changebit.S
+++ b/arch/arm/lib/changebit.S
@@ -12,6 +12,4 @@
#include "bitops.h"
.text
-ENTRY(_change_bit)
- bitop eor
-ENDPROC(_change_bit)
+bitop _change_bit, eor
diff --git a/arch/arm/lib/clearbit.S b/arch/arm/lib/clearbit.S
index 4c04c3b..f6b75fb 100644
--- a/arch/arm/lib/clearbit.S
+++ b/arch/arm/lib/clearbit.S
@@ -12,6 +12,4 @@
#include "bitops.h"
.text
-ENTRY(_clear_bit)
- bitop bic
-ENDPROC(_clear_bit)
+bitop _clear_bit, bic
diff --git a/arch/arm/lib/setbit.S b/arch/arm/lib/setbit.S
index bbee5c6..618feda 100644
--- a/arch/arm/lib/setbit.S
+++ b/arch/arm/lib/setbit.S
@@ -12,6 +12,4 @@
#include "bitops.h"
.text
-ENTRY(_set_bit)
- bitop orr
-ENDPROC(_set_bit)
+bitop _set_bit, orr
diff --git a/arch/arm/lib/testchangebit.S b/arch/arm/lib/testchangebit.S
index 15a4d43..4becdc3 100644
--- a/arch/arm/lib/testchangebit.S
+++ b/arch/arm/lib/testchangebit.S
@@ -12,6 +12,4 @@
#include "bitops.h"
.text
-ENTRY(_test_and_change_bit)
- testop eor, str
-ENDPROC(_test_and_change_bit)
+testop _test_and_change_bit, eor, str
diff --git a/arch/arm/lib/testclearbit.S b/arch/arm/lib/testclearbit.S
index 521b66b..918841d 100644
--- a/arch/arm/lib/testclearbit.S
+++ b/arch/arm/lib/testclearbit.S
@@ -12,6 +12,4 @@
#include "bitops.h"
.text
-ENTRY(_test_and_clear_bit)
- testop bicne, strne
-ENDPROC(_test_and_clear_bit)
+testop _test_and_clear_bit, bicne, strne
diff --git a/arch/arm/lib/testsetbit.S b/arch/arm/lib/testsetbit.S
index 1c98cc2..8d1b2fe 100644
--- a/arch/arm/lib/testsetbit.S
+++ b/arch/arm/lib/testsetbit.S
@@ -12,6 +12,4 @@
#include "bitops.h"
.text
-ENTRY(_test_and_set_bit)
- testop orreq, streq
-ENDPROC(_test_and_set_bit)
+testop _test_and_set_bit, orreq, streq