1 files changed, 23 insertions, 2 deletions
diff --git a/hw/virtio-console.c b/hw/virtio-console.c
index b076331d37..7ebfa26516 100644
--- a/hw/virtio-console.c
+++ b/hw/virtio-console.c
@@ -12,6 +12,7 @@
 
 #include "qemu-char.h"
 #include "qemu-error.h"
+#include "trace.h"
 #include "virtio-serial.h"
 
 typedef struct VirtConsole {
@@ -24,8 +25,26 @@ typedef struct VirtConsole {
 static ssize_t flush_buf(VirtIOSerialPort *port, const uint8_t *buf, size_t len)
 {
     VirtConsole *vcon = DO_UPCAST(VirtConsole, port, port);
-
-    return qemu_chr_write(vcon->chr, buf, len);
+    ssize_t ret;
+
+    ret = qemu_chr_write(vcon->chr, buf, len);
+    trace_virtio_console_flush_buf(port->id, len, ret);
+
+    if (ret < 0) {
+        /*
+         * Ideally we'd get a better error code than just -1, but
+         * that's what the chardev interface gives us right now.  If
+         * we had a finer-grained message, like -EPIPE, we could close
+         * this connection.  Absent such error messages, the most we
+         * can do is to return 0 here.
+         *
+         * This will prevent stray -1 values to go to
+         * virtio-serial-bus.c and cause abort()s in
+         * do_flush_queued_data().
+         */
+        ret = 0;
+    }
+    return ret;
 }
 
 /* Callback function that's called when the guest opens the port */
@@ -57,6 +76,7 @@ static void chr_read(void *opaque, const uint8_t *buf, int size)
 {
     VirtConsole *vcon = opaque;
 
+    trace_virtio_console_chr_read(vcon->port.id, size);
     virtio_serial_write(&vcon->port, buf, size);
 }
 
@@ -64,6 +84,7 @@ static void chr_event(void *opaque, int event)
 {
     VirtConsole *vcon = opaque;
 
+    trace_virtio_console_chr_event(vcon->port.id, event);
     switch (event) {
     case CHR_EVENT_OPENED:
         virtio_serial_open(&vcon->port);