arm64: text replication: handle aarch64_insn_write_literal_u64()

aarch64_insn_write_literal_u64() was introduced in v6.3-rc1 for
updating ftrace ops pointers in the kernel text. This needs to be
fixed up for kernel text replication, so provide a version that
will update the mapping.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

3 files changed, 28 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/ktext.h b/arch/arm64/include/asm/ktext.h
index 289e11289c06..2be2b2a9c9eb 100644
--- a/arch/arm64/include/asm/ktext.h
+++ b/arch/arm64/include/asm/ktext.h
@@ -10,6 +10,7 @@
 #ifdef CONFIG_REPLICATE_KTEXT
 
 void ktext_replication_init(void);
+void ktext_replication_write(void *addr, void *data, size_t size);
 void __kprobes ktext_replication_patch(u32 *tp,  __le32 insn);
 void ktext_replication_patch_alternative(__le32 *src, int nr_inst);
 
@@ -19,6 +20,10 @@ static inline void ktext_replication_init(void)
 {
 }
 
+static inline void ktext_replication_write(void *addr, void *data, size_t size)
+{
+}
+
 static inline void __kprobes ktext_replication_patch(u32 *tp,  __le32 insn)
 {
 }
diff --git a/arch/arm64/kernel/patching.c b/arch/arm64/kernel/patching.c
index 627fff6ddda2..b670e159a766 100644
--- a/arch/arm64/kernel/patching.c
+++ b/arch/arm64/kernel/patching.c
@@ -103,6 +103,8 @@ noinstr int aarch64_insn_write_literal_u64(void *addr, u64 val)
 	patch_unmap(FIX_TEXT_POKE0);
 	raw_spin_unlock_irqrestore(&patch_lock, flags);
 
+	ktext_replication_write(addr, &val, sizeof(val));
+
 	return ret;
 }
 
diff --git a/arch/arm64/mm/ktext.c b/arch/arm64/mm/ktext.c
index 04b5ceddae4e..0017e7760d36 100644
--- a/arch/arm64/mm/ktext.c
+++ b/arch/arm64/mm/ktext.c
@@ -17,6 +17,27 @@
 
 static void *kernel_texts[MAX_NUMNODES];
 
+noinstr void ktext_replication_write(void *addr, void *data, size_t size)
+{
+	unsigned long offset;
+	void *ptr;
+	int nid;
+
+	if (!is_kernel_text((unsigned long)addr))
+		return;
+
+	offset = (unsigned long)addr - (unsigned long)_stext;
+
+	for_each_node(nid) {
+		if (!kernel_texts[nid] || !nid)
+			continue;
+
+		ptr = kernel_texts[nid] + offset;
+
+		memcpy(ptr, data, size);
+	}
+}
+
 void __kprobes ktext_replication_patch(u32 *tp, __le32 insn)
 {
 	unsigned long offset;