From e1cf9ca84a1aac86291f7e10c1bcbb86ee9b0e9c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alex=20Benn=C3=A9e?= <alex.bennee@linaro.org>
Date: Mon, 26 Feb 2018 05:08:12 -0500
Subject: [PATCH] qom/cpu: atomically clear the tb_jmp_cache

The ThreadSanitizer rightly complains that something initialised with a
normal access is later updated and read atomically.

Backports commit ce7cf6a973f4b614162b9518954d441fa5e32fc6 from qemu
---
 qemu/qom/cpu.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/qemu/qom/cpu.c b/qemu/qom/cpu.c
index 22e7843e..3ac22786 100644
--- a/qemu/qom/cpu.c
+++ b/qemu/qom/cpu.c
@@ -155,6 +155,7 @@ void cpu_reset(CPUState *cpu)
 static void cpu_common_reset(CPUState *cpu)
 {
     CPUClass *cc = CPU_GET_CLASS(cpu->uc, cpu);
+    int i;
 
     if (qemu_loglevel_mask(CPU_LOG_RESET)) {
         qemu_log("CPU Reset (CPU %d)\n", cpu->cpu_index);
@@ -170,7 +171,10 @@ static void cpu_common_reset(CPUState *cpu)
     cpu->can_do_io = 0;
     cpu->exception_index = -1;
     cpu->crash_occurred = false;
-    memset(cpu->tb_jmp_cache, 0, TB_JMP_CACHE_SIZE * sizeof(void *));
+
+    for (i = 0; i < TB_JMP_CACHE_SIZE; ++i) {
+        atomic_set(&cpu->tb_jmp_cache[i], NULL);
+    }
 }
 
 static bool cpu_common_has_work(CPUState *cs)