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));
 	}
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 23f25acf43a9..cce18c85d2e8 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -1315,15 +1315,15 @@ static int armpmu_device_probe(struct platform_device *pdev)
 	if (!cpu_pmu)
 		return -ENODEV;
 
-	irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL);
-	if (!irqs)
-		return -ENOMEM;
-
 	/* Don't bother with PPIs; they're already affine */
 	irq = platform_get_irq(pdev, 0);
 	if (irq >= 0 && irq_is_percpu(irq))
 		return 0;
 
+	irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL);
+	if (!irqs)
+		return -ENOMEM;
+
 	for (i = 0; i < pdev->num_resources; ++i) {
 		struct device_node *dn;
 		int cpu;
diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c
index 74c256744b25..f3d6221cd5bd 100644
--- a/arch/arm64/mm/dump.c
+++ b/arch/arm64/mm/dump.c
@@ -328,10 +328,12 @@ static int ptdump_init(void)
 			for (j = 0; j < pg_level[i].num; j++)
 				pg_level[i].mask |= pg_level[i].bits[j].mask;
 
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
 	address_markers[VMEMMAP_START_NR].start_address =
 				(unsigned long)virt_to_page(PAGE_OFFSET);
 	address_markers[VMEMMAP_END_NR].start_address =
 				(unsigned long)virt_to_page(high_memory);
+#endif
 
 	pe = debugfs_create_file("kernel_page_tables", 0400, NULL, NULL,
 				 &ptdump_fops);
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index edba042b2325..dc6a4842683a 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -487,7 +487,7 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 			return -EINVAL;
 		}
 
-		imm64 = (u64)insn1.imm << 32 | imm;
+		imm64 = (u64)insn1.imm << 32 | (u32)imm;
 		emit_a64_mov_i64(dst, imm64, ctx);
 
 		return 1;