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Diffstat (limited to 'arch/arm64/kernel/alternative.c')
-rw-r--r--arch/arm64/kernel/alternative.c53
1 files changed, 1 insertions, 52 deletions
diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c
index 21033bba9390..28f8365edc4c 100644
--- a/arch/arm64/kernel/alternative.c
+++ b/arch/arm64/kernel/alternative.c
@@ -24,7 +24,6 @@
#include <asm/cacheflush.h>
#include <asm/alternative.h>
#include <asm/cpufeature.h>
-#include <asm/insn.h>
#include <linux/stop_machine.h>
extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
@@ -34,48 +33,6 @@ struct alt_region {
struct alt_instr *end;
};
-/*
- * Decode the imm field of a b/bl instruction, and return the byte
- * offset as a signed value (so it can be used when computing a new
- * branch target).
- */
-static s32 get_branch_offset(u32 insn)
-{
- s32 imm = aarch64_insn_decode_immediate(AARCH64_INSN_IMM_26, insn);
-
- /* sign-extend the immediate before turning it into a byte offset */
- return (imm << 6) >> 4;
-}
-
-static u32 get_alt_insn(u8 *insnptr, u8 *altinsnptr)
-{
- u32 insn;
-
- aarch64_insn_read(altinsnptr, &insn);
-
- /* Stop the world on instructions we don't support... */
- BUG_ON(aarch64_insn_is_cbz(insn));
- BUG_ON(aarch64_insn_is_cbnz(insn));
- BUG_ON(aarch64_insn_is_bcond(insn));
- /* ... and there is probably more. */
-
- if (aarch64_insn_is_b(insn) || aarch64_insn_is_bl(insn)) {
- enum aarch64_insn_branch_type type;
- unsigned long target;
-
- if (aarch64_insn_is_b(insn))
- type = AARCH64_INSN_BRANCH_NOLINK;
- else
- type = AARCH64_INSN_BRANCH_LINK;
-
- target = (unsigned long)altinsnptr + get_branch_offset(insn);
- insn = aarch64_insn_gen_branch_imm((unsigned long)insnptr,
- target, type);
- }
-
- return insn;
-}
-
static int __apply_alternatives(void *alt_region)
{
struct alt_instr *alt;
@@ -83,9 +40,6 @@ static int __apply_alternatives(void *alt_region)
u8 *origptr, *replptr;
for (alt = region->begin; alt < region->end; alt++) {
- u32 insn;
- int i;
-
if (!cpus_have_cap(alt->cpufeature))
continue;
@@ -95,12 +49,7 @@ static int __apply_alternatives(void *alt_region)
origptr = (u8 *)&alt->orig_offset + alt->orig_offset;
replptr = (u8 *)&alt->alt_offset + alt->alt_offset;
-
- for (i = 0; i < alt->alt_len; i += sizeof(insn)) {
- insn = get_alt_insn(origptr + i, replptr + i);
- aarch64_insn_write(origptr + i, insn);
- }
-
+ memcpy(origptr, replptr, alt->alt_len);
flush_icache_range((uintptr_t)origptr,
(uintptr_t)(origptr + alt->alt_len));
}