From 7e6d21d27c8316fbaca3ad8a7f11fbb33cd8f8da Mon Sep 17 00:00:00 2001
From: lazymio <mio@lazym.io>
Date: Sun, 3 Apr 2022 21:44:09 +0200
Subject: [PATCH] Fix memory leak in code_gen_buffer

---
 qemu/accel/tcg/translate-all.c | 12 ++++++++----
 qemu/include/tcg/tcg.h         |  2 ++
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/qemu/accel/tcg/translate-all.c b/qemu/accel/tcg/translate-all.c
index 0d50cf76..9a6f79fe 100644
--- a/qemu/accel/tcg/translate-all.c
+++ b/qemu/accel/tcg/translate-all.c
@@ -879,16 +879,18 @@ static inline void *alloc_code_gen_buffer(struct uc_struct *uc)
 void free_code_gen_buffer(struct uc_struct *uc)
 {
     TCGContext *tcg_ctx = uc->tcg_ctx;
-    if (tcg_ctx->code_gen_buffer) {
-        VirtualFree(tcg_ctx->code_gen_buffer, 0, MEM_RELEASE);
+    if (tcg_ctx->initial_buffer) {
+        VirtualFree(tcg_ctx->initial_buffer, 0, MEM_RELEASE);
     }
 }
 #else
 void free_code_gen_buffer(struct uc_struct *uc)
 {
     TCGContext *tcg_ctx = uc->tcg_ctx;
-    if (tcg_ctx->code_gen_buffer) {
-        munmap(tcg_ctx->code_gen_buffer, tcg_ctx->code_gen_buffer_size);
+    if (tcg_ctx->initial_buffer) {
+        if (munmap(tcg_ctx->initial_buffer, tcg_ctx->initial_buffer_size)) {
+            perror("fail code_gen_buffer");
+        }
     }
 }
 
@@ -953,6 +955,8 @@ static inline void code_gen_alloc(struct uc_struct *uc, size_t tb_size)
     TCGContext *tcg_ctx = uc->tcg_ctx;
     tcg_ctx->code_gen_buffer_size = size_code_gen_buffer(tb_size);
     tcg_ctx->code_gen_buffer = alloc_code_gen_buffer(uc);
+    tcg_ctx->initial_buffer = tcg_ctx->code_gen_buffer;
+    tcg_ctx->initial_buffer_size = tcg_ctx->code_gen_buffer_size;
     if (tcg_ctx->code_gen_buffer == NULL) {
         fprintf(stderr, "Could not allocate dynamic translator buffer\n");
         exit(1);
diff --git a/qemu/include/tcg/tcg.h b/qemu/include/tcg/tcg.h
index 85eec860..33acbd7c 100644
--- a/qemu/include/tcg/tcg.h
+++ b/qemu/include/tcg/tcg.h
@@ -642,6 +642,8 @@ struct TCGContext {
     void *code_gen_prologue;
     void *code_gen_epilogue;
     void *code_gen_buffer;
+    void *initial_buffer;
+    size_t initial_buffer_size;
     size_t code_gen_buffer_size;
     void *code_gen_ptr;
     void *data_gen_ptr;