Index: sys/boot/i386/libi386/i386_module.c
===================================================================
--- sys/boot/i386/libi386/i386_module.c
+++ sys/boot/i386/libi386/i386_module.c
@@ -32,12 +32,35 @@
  *
  */
 
+#include <stand.h>
+#include <string.h>
+#include <machine/cpufunc.h>
+
+/* See the kernel's function identify_hypervisor(). */
+static int
+running_on_hypervisor(void)
+{
+    unsigned int regs[4];
+
+    do_cpuid(1, regs);
+    return (regs[2] & 0x80000000);
+}
+
 /*
  * Use voodoo to load modules required by current hardware.
  */
 int
 i386_autoload(void)
 {
+    if (running_on_hypervisor()) {
+        /*
+         * vt(4)'s graphics mode is slow when FreeBSD guest runs on
+         * hypervisors, especially on Hyper-V (e.g., 1 line of boot message
+         * per second), but luckily vt(4) is fast enough in text mode.
+         */
+        if (getenv("hw.vga.textmode") == NULL)
+            setenv("hw.vga.textmode", "1", 1);
+    }
 
     /* XXX use PnP to locate stuff here */
     return(0);