Reviewed-by: Richard Henderson <r...@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
cpu-exec.c | 6 +++++-
qom/cpu.c | 2 ++
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/cpu-exec.c b/cpu-exec.c
index 567ae8b..e24c640 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -507,8 +507,12 @@ int cpu_exec(CPUState *cpu)
* loop. Whatever requested the exit will also
* have set something else (eg exit_request or
* interrupt_request) which we will handle
- * next time around the loop.
+ * next time around the loop. But we need to
+ * ensure the tcg_exit_req read in generated code
+ * comes before the next read of cpu->exit_request
+ * or cpu->interrupt_request.
*/
+ smp_rmb();
next_tb = 0;
break;
case TB_EXIT_ICOUNT_EXPIRED:
diff --git a/qom/cpu.c b/qom/cpu.c
index 62f4b5d..02b56f7 100644
--- a/qom/cpu.c
+++ b/qom/cpu.c
@@ -114,6 +114,8 @@ void cpu_reset_interrupt(CPUState *cpu, int mask)
void cpu_exit(CPUState *cpu)
{
cpu->exit_request = 1;
+ /* Ensure cpu_exec will see the exit request after TCG has exited. */
+ smp_wmb();
cpu->tcg_exit_req = 1;
}
--
2.4.3
