4 files changed, 46 insertions, 6 deletions

diff --git a/arch/arm64/include/asm/alternative.h b/arch/arm64/include/asm/alternative.h
index f6d206e7f9e9..d261f01e2bae 100644
--- a/arch/arm64/include/asm/alternative.h
+++ b/arch/arm64/include/asm/alternative.h
@@ -13,7 +13,8 @@ struct alt_instr {
         u8  alt_len;            /* size of new instruction(s), <= orig_len */
 };
 
-void apply_alternatives(void);
+void apply_alternatives_all(void);
+void apply_alternatives(void *start, size_t length);
 void free_alternatives_memory(void);
 
 #define ALTINSTR_ENTRY(feature)                                               \
diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c
index 1a3badab800a..ad7821d64a1d 100644
--- a/arch/arm64/kernel/alternative.c
+++ b/arch/arm64/kernel/alternative.c
@@ -28,12 +28,18 @@
 
 extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
 
-static int __apply_alternatives(void *dummy)
+struct alt_region {
+        struct alt_instr *begin;
+        struct alt_instr *end;
+};
+
+static int __apply_alternatives(void *alt_region)
 {
         struct alt_instr *alt;
+        struct alt_region *region = alt_region;
         u8 *origptr, *replptr;
 
-        for (alt = __alt_instructions; alt < __alt_instructions_end; alt++) {
+        for (alt = region->begin; alt < region->end; alt++) {
                 if (!cpus_have_cap(alt->cpufeature))
                         continue;
 
@@ -51,10 +57,25 @@ static int __apply_alternatives(void *dummy)
         return 0;
 }
 
-void apply_alternatives(void)
+void apply_alternatives_all(void)
 {
+        struct alt_region region = {
+                .begin  = __alt_instructions,
+                .end    = __alt_instructions_end,
+        };
+
         /* better not try code patching on a live SMP system */
-        stop_machine(__apply_alternatives, NULL, NULL);
+        stop_machine(__apply_alternatives, &region, NULL);
+}
+
+void apply_alternatives(void *start, size_t length)
+{
+        struct alt_region region = {
+                .begin  = start,
+                .end    = start + length,
+        };
+
+        __apply_alternatives(&region);
 }
 
 void free_alternatives_memory(void)
diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index 1eb1cc955139..fd027b101de5 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -26,6 +26,7 @@
 #include <linux/moduleloader.h>
 #include <linux/vmalloc.h>
 #include <asm/insn.h>
+#include <asm/sections.h>
 
 #define AARCH64_INSN_IMM_MOVNZ          AARCH64_INSN_IMM_MAX
 #define AARCH64_INSN_IMM_MOVK           AARCH64_INSN_IMM_16
@@ -394,3 +395,20 @@ overflow:
                me->name, (int)ELF64_R_TYPE(rel[i].r_info), val);
         return -ENOEXEC;
 }
+
+int module_finalize(const Elf_Ehdr *hdr,
+                    const Elf_Shdr *sechdrs,
+                    struct module *me)
+{
+        const Elf_Shdr *s, *se;
+        const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+        for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) {
+                if (strcmp(".altinstructions", secstrs + s->sh_name) == 0) {
+                        apply_alternatives((void *)s->sh_addr, s->sh_size);
+                        return 0;
+                }
+        }
+
+        return 0;
+}
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 0ef87896e4ae..7ae6ee085261 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -310,7 +310,7 @@ void cpu_die(void)
 void __init smp_cpus_done(unsigned int max_cpus)
 {
         pr_info("SMP: Total of %d processors activated.\n", num_online_cpus());
-        apply_alternatives();
+        apply_alternatives_all();
 }
 
 void __init smp_prepare_boot_cpu(void)