[PATCH v8 13/21] main: keep rcu_atfork callback enabled for qtest

[Bulekov, Alexander]

The qtest-based fuzzer makes use of forking to reset-state between
tests. Keep the callback enabled, so the call_rcu thread gets created
within the child process.

Signed-off-by: Alexander Bulekov <alx...@bu.edu>
---
 vl.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/vl.c b/vl.c
index bb77935f04..cf8e2d3ebb 100644
--- a/vl.c
+++ b/vl.c
@@ -3794,7 +3794,14 @@ void qemu_init(int argc, char **argv, char **envp)
     set_memory_options(&ram_slots, &maxram_size, machine_class);
 
     os_daemonize();
-    rcu_disable_atfork();
+
+    /*
+     * If QTest is enabled, keep the rcu_atfork enabled, since system processes
+     * may be forked testing purposes (e.g. fork-server based fuzzing)
+     */
+    if (!qtest_enabled()) {
+        rcu_disable_atfork();
+    }
 
     if (pid_file && !qemu_write_pidfile(pid_file, &err)) {
         error_reportf_err(err, "cannot create PID file: ");
-- 
2.23.0