1 files changed, 31 insertions, 0 deletions
diff --git a/arch/x86/kernel/static_call.c b/arch/x86/kernel/static_call.c
new file mode 100644
index 000000000000..0565825970af
--- /dev/null
+++ b/arch/x86/kernel/static_call.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/static_call.h>
+#include <linux/memory.h>
+#include <linux/bug.h>
+#include <asm/text-patching.h>
+
+static void __static_call_transform(void *insn, u8 opcode, void *func)
+{
+	const void *code = text_gen_insn(opcode, insn, func);
+
+	if (WARN_ONCE(*(u8 *)insn != opcode,
+		      "unexpected static call insn opcode 0x%x at %pS\n",
+		      opcode, insn))
+		return;
+
+	if (memcmp(insn, code, CALL_INSN_SIZE) == 0)
+		return;
+
+	text_poke_bp(insn, code, CALL_INSN_SIZE, NULL);
+}
+
+void arch_static_call_transform(void *site, void *tramp, void *func)
+{
+	mutex_lock(&text_mutex);
+
+	if (tramp)
+		__static_call_transform(tramp, JMP32_INSN_OPCODE, func);
+
+	mutex_unlock(&text_mutex);
+}
+EXPORT_SYMBOL_GPL(arch_static_call_transform);