[PATCH v2] arm64: fix endianness annotation for __apply_alternatives()/get_alt_insn()
Luc Van Oostenryck
luc.vanoostenryck at gmail.com
Thu Jun 29 07:40:12 PDT 2017
get_alt_insn() is used to read and create ARM instructions, which
are always stored in memory in little-endian order. These values
are thus correctly converted to/from native order when processed
but the pointers used to hold the address of these instructions
are declared as for native order values.
Fix this by declaring the pointers as __le32* instead of u32* and
make the few appropriate needed changes like removing the unneeded
cast '(u32*)' in front of __ALT_PTR()'s definition.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck at gmail.com>
---
Change since v1:
- remove the unneeded cast '(u32*)' in front of __ALT_PTR()'s definition.
- remove the now unneeded forced cast to __le32* when using
ALT_ORIG_PTR() or ALT_REPL_PTR().
- remove an unnneded cast in front of lm_alias().
arch/arm64/kernel/alternative.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c
index 8840c109c..6dd0a3a3e 100644
--- a/arch/arm64/kernel/alternative.c
+++ b/arch/arm64/kernel/alternative.c
@@ -28,7 +28,7 @@
#include <asm/sections.h>
#include <linux/stop_machine.h>
-#define __ALT_PTR(a,f) (u32 *)((void *)&(a)->f + (a)->f)
+#define __ALT_PTR(a,f) ((void *)&(a)->f + (a)->f)
#define ALT_ORIG_PTR(a) __ALT_PTR(a, orig_offset)
#define ALT_REPL_PTR(a) __ALT_PTR(a, alt_offset)
@@ -60,7 +60,7 @@ static bool branch_insn_requires_update(struct alt_instr *alt, unsigned long pc)
#define align_down(x, a) ((unsigned long)(x) & ~(((unsigned long)(a)) - 1))
-static u32 get_alt_insn(struct alt_instr *alt, u32 *insnptr, u32 *altinsnptr)
+static u32 get_alt_insn(struct alt_instr *alt, __le32 *insnptr, __le32 *altinsnptr)
{
u32 insn;
@@ -109,7 +109,7 @@ static void __apply_alternatives(void *alt_region, bool use_linear_alias)
{
struct alt_instr *alt;
struct alt_region *region = alt_region;
- u32 *origptr, *replptr, *updptr;
+ __le32 *origptr, *replptr, *updptr;
for (alt = region->begin; alt < region->end; alt++) {
u32 insn;
@@ -124,7 +124,7 @@ static void __apply_alternatives(void *alt_region, bool use_linear_alias)
origptr = ALT_ORIG_PTR(alt);
replptr = ALT_REPL_PTR(alt);
- updptr = use_linear_alias ? (u32 *)lm_alias(origptr) : origptr;
+ updptr = use_linear_alias ? lm_alias(origptr) : origptr;
nr_inst = alt->alt_len / sizeof(insn);
for (i = 0; i < nr_inst; i++) {
--
2.13.0
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