path: root/arch/arm/lib/copy_from_user.S
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authorLin Yongting <linyongting@gmail.com>2014-11-26 14:38:33 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2014-11-27 16:00:25 +0000
commit279f487e0b471577e2b3c134e2ff9af939129d0f (patch)
tree6c772b214b5110c695a2774a5785489bc5c6cfc9 /arch/arm/lib/copy_from_user.S
parent207a6cb06990c298d0eac982e053d370e216d93d (diff)
ARM: 8225/1: Add unwinding support for memory copy functions
The memory copy functions(memcpy, __copy_from_user, __copy_to_user) never had unwinding annotations added. Currently, when accessing invalid pointer by these functions occurs the backtrace shown will stop at these functions or some completely unrelated function. Add unwinding annotations in hopes of getting a more useful backtrace in following cases: 1. die on accessing invalid pointer by these functions 2. kprobe trapped at any instruction within these functions 3. interrupted at any instruction within these functions Signed-off-by: Lin Yongting <linyongting@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/lib/copy_from_user.S')
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/arm/lib/copy_from_user.S b/arch/arm/lib/copy_from_user.S
index 66a477a3e3cc..7a235b9952be 100644
--- a/arch/arm/lib/copy_from_user.S
+++ b/arch/arm/lib/copy_from_user.S
@@ -12,6 +12,7 @@
#include <linux/linkage.h>
#include <asm/assembler.h>
+#include <asm/unwind.h>
* Prototype:
@@ -77,6 +78,10 @@
stmdb sp!, {r0, r2, r3, \reg1, \reg2}
+ .macro usave reg1 reg2
+ UNWIND( .save {r0, r2, r3, \reg1, \reg2} )
+ .endm
.macro exit reg1 reg2
add sp, sp, #8
ldmfd sp!, {r0, \reg1, \reg2}