[PATCH 4/4] fuzz: run the main-loop in fork-server process

[Alexander Bulekov <alxndr@bu.edu>]

Without this, the time since the last main-loop keeps increasing, as the
fuzzer runs. The forked children need to handle all the "past-due"
timers, slowing them down, over time. With this change, the
parent/fork-server process runs the main-loop, while waiting on the
child, ensuring that the timer events do not pile up, over time.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
---
 tests/qtest/fuzz/i440fx_fuzz.c      | 1 +
 tests/qtest/fuzz/virtio_net_fuzz.c  | 2 ++
 tests/qtest/fuzz/virtio_scsi_fuzz.c | 2 ++
 3 files changed, 5 insertions(+)

I'm working on another series to abstract away the details of resetting
qemu state between runs from the individual targets. That should relieve
us from needing to add this for each new fuzzing target.

diff --git a/tests/qtest/fuzz/i440fx_fuzz.c b/tests/qtest/fuzz/i440fx_fuzz.c
index 90e75ffaea..8449f81687 100644
--- a/tests/qtest/fuzz/i440fx_fuzz.c
+++ b/tests/qtest/fuzz/i440fx_fuzz.c
@@ -138,6 +138,7 @@ static void i440fx_fuzz_qos_fork(QTestState *s,
         i440fx_fuzz_qos(s, Data, Size);
         _Exit(0);
     } else {
+        flush_events(s);
         wait(NULL);
     }
 }
diff --git a/tests/qtest/fuzz/virtio_net_fuzz.c b/tests/qtest/fuzz/virtio_net_fuzz.c
index d08a47e278..a33bd73067 100644
--- a/tests/qtest/fuzz/virtio_net_fuzz.c
+++ b/tests/qtest/fuzz/virtio_net_fuzz.c
@@ -122,6 +122,7 @@ static void virtio_net_fork_fuzz(QTestState *s,
         flush_events(s);
         _Exit(0);
     } else {
+        flush_events(s);
         wait(NULL);
     }
 }
@@ -134,6 +135,7 @@ static void virtio_net_fork_fuzz_check_used(QTestState *s,
         flush_events(s);
         _Exit(0);
     } else {
+        flush_events(s);
         wait(NULL);
     }
 }
diff --git a/tests/qtest/fuzz/virtio_scsi_fuzz.c b/tests/qtest/fuzz/virtio_scsi_fuzz.c
index 3b95247f12..51dce491ab 100644
--- a/tests/qtest/fuzz/virtio_scsi_fuzz.c
+++ b/tests/qtest/fuzz/virtio_scsi_fuzz.c
@@ -145,6 +145,7 @@ static void virtio_scsi_fork_fuzz(QTestState *s,
         flush_events(s);
         _Exit(0);
     } else {
+        flush_events(s);
         wait(NULL);
     }
 }
@@ -164,6 +165,7 @@ static void virtio_scsi_with_flag_fuzz(QTestState *s,
         }
         _Exit(0);
     } else {
+        flush_events(s);
         wait(NULL);
     }
 }
-- 
2.26.2