--- vmmon-only/freebsd/driver.c.orig	2008-03-04 10:05:14.000000000 +0300
+++ vmmon-only/freebsd/driver.c	2008-03-04 10:09:23.000000000 +0300
@@ -397,12 +397,12 @@
 	if ((error = falloc(td, &fp, &fd)) != 0)
 		return error;
 
-	FILEDESC_LOCK(p->p_fd);
+	FILEDESC_XLOCK(p->p_fd);
 	fp->f_data = data;
 	fp->f_flag = flags & FMASK;
 	fp->f_ops = &vmmon_fileops;
 	fp->f_type = DTYPE_SOCKET;
-	FILEDESC_UNLOCK(p->p_fd);
+	FILEDESC_XUNLOCK(p->p_fd);
 
 #if __FreeBSD_version >= 501111
 	/* falloc now returns TWO references to the file, not one. */
@@ -1309,6 +1309,19 @@
 	return FALSE;
 }
 
+static vm_paddr_t
+get_avail_end(void)
+{
+	vm_paddr_t avail_end;
+	int i;
+	avail_end = phys_avail[1];
+	for (i = 0; phys_avail[i + 1]; i += 2) {
+		if (phys_avail[i + 1] > avail_end)
+			avail_end = phys_avail[i + 1];
+	}
+	return avail_end;
+}
+
 /*
  * Allocate and lock numPages of memory physically continguous addresses
  * below 4GB.
@@ -1341,6 +1354,7 @@
 		VMDEBUG("vmmon_alloc_low_pages: malloc MemRange failed\n");
 		return ENOMEM;
 	}
+	vm_paddr_t avail_end = get_avail_end();
 	if (avail_end > ISA_DMA_BOUNCE_THRESHOLD)
 		high = trunc_page(ISA_DMA_BOUNCE_THRESHOLD);
 	else