[PATCH] arm64: fix endianness annotation for __apply_alternatives()/get_alt_insn()

[Luc Van Oostenryck]

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.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck at gmail.com>
---
 arch/arm64/kernel/alternative.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c
index 8840c109c..56bfda8cb 100644
--- a/arch/arm64/kernel/alternative.c
+++ b/arch/arm64/kernel/alternative.c
@@ -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;
@@ -122,9 +122,9 @@ static void __apply_alternatives(void *alt_region, bool use_linear_alias)
 
 		pr_info_once("patching kernel code\n");
 
-		origptr = ALT_ORIG_PTR(alt);
-		replptr = ALT_REPL_PTR(alt);
-		updptr = use_linear_alias ? (u32 *)lm_alias(origptr) : origptr;
+		origptr = (__le32 __force *) ALT_ORIG_PTR(alt);
+		replptr = (__le32 __force *) ALT_REPL_PTR(alt);
+		updptr = use_linear_alias ? (__le32 *)lm_alias(origptr) : origptr;
 		nr_inst = alt->alt_len / sizeof(insn);
 
 		for (i = 0; i < nr_inst; i++) {
-- 
2.13.0