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-rw-r--r--include/exec/cpu_ldst.h20
-rw-r--r--include/exec/cpu_ldst_useronly_template.h12
2 files changed, 26 insertions, 6 deletions
diff --git a/include/exec/cpu_ldst.h b/include/exec/cpu_ldst.h
index a08b11bd2c..9de8c93303 100644
--- a/include/exec/cpu_ldst.h
+++ b/include/exec/cpu_ldst.h
@@ -89,6 +89,26 @@ typedef target_ulong abi_ptr;
 
 extern __thread uintptr_t helper_retaddr;
 
+static inline void set_helper_retaddr(uintptr_t ra)
+{
+    helper_retaddr = ra;
+    /*
+     * Ensure that this write is visible to the SIGSEGV handler that
+     * may be invoked due to a subsequent invalid memory operation.
+     */
+    signal_barrier();
+}
+
+static inline void clear_helper_retaddr(void)
+{
+    /*
+     * Ensure that previous memory operations have succeeded before
+     * removing the data visible to the signal handler.
+     */
+    signal_barrier();
+    helper_retaddr = 0;
+}
+
 /* In user-only mode we provide only the _code and _data accessors. */
 
 #define MEMSUFFIX _data
diff --git a/include/exec/cpu_ldst_useronly_template.h b/include/exec/cpu_ldst_useronly_template.h
index bc45e2b8d4..e65733f7e2 100644
--- a/include/exec/cpu_ldst_useronly_template.h
+++ b/include/exec/cpu_ldst_useronly_template.h
@@ -78,9 +78,9 @@ glue(glue(glue(cpu_ld, USUFFIX), MEMSUFFIX), _ra)(CPUArchState *env,
                                                   uintptr_t retaddr)
 {
     RES_TYPE ret;
-    helper_retaddr = retaddr;
+    set_helper_retaddr(retaddr);
     ret = glue(glue(cpu_ld, USUFFIX), MEMSUFFIX)(env, ptr);
-    helper_retaddr = 0;
+    clear_helper_retaddr();
     return ret;
 }
 
@@ -102,9 +102,9 @@ glue(glue(glue(cpu_lds, SUFFIX), MEMSUFFIX), _ra)(CPUArchState *env,
                                                   uintptr_t retaddr)
 {
     int ret;
-    helper_retaddr = retaddr;
+    set_helper_retaddr(retaddr);
     ret = glue(glue(cpu_lds, SUFFIX), MEMSUFFIX)(env, ptr);
-    helper_retaddr = 0;
+    clear_helper_retaddr();
     return ret;
 }
 #endif
@@ -128,9 +128,9 @@ glue(glue(glue(cpu_st, SUFFIX), MEMSUFFIX), _ra)(CPUArchState *env,
                                                   RES_TYPE v,
                                                   uintptr_t retaddr)
 {
-    helper_retaddr = retaddr;
+    set_helper_retaddr(retaddr);
     glue(glue(cpu_st, SUFFIX), MEMSUFFIX)(env, ptr, v);
-    helper_retaddr = 0;
+    clear_helper_retaddr();
 }
 #endif