Index: sys/arch/sparc64/conf/GENERIC
===================================================================
RCS file: /cvsroot/src/sys/arch/sparc64/conf/GENERIC,v
retrieving revision 1.191
diff -u -r1.191 GENERIC
--- sys/arch/sparc64/conf/GENERIC	22 Jun 2016 20:12:59 -0000	1.191
+++ sys/arch/sparc64/conf/GENERIC	14 Aug 2016 19:19:27 -0000
@@ -277,6 +277,7 @@
 
 # Virtual devices for sun4v systems.
 vrtc0	at vbus?
+vdsk*	at cbus?
 
 #### Serial port configuration
 
Index: sys/arch/sparc64/conf/files.sparc64
===================================================================
RCS file: /cvsroot/src/sys/arch/sparc64/conf/files.sparc64,v
retrieving revision 1.151
diff -u -r1.151 files.sparc64
--- sys/arch/sparc64/conf/files.sparc64	22 Jun 2016 20:12:59 -0000	1.151
+++ sys/arch/sparc64/conf/files.sparc64	14 Aug 2016 19:19:27 -0000
@@ -325,3 +325,11 @@
 device	vrtc
 attach	vrtc at vbus
 file	arch/sparc64/dev/vrtc.c			vrtc
+
+define	ldc
+file	arch/sparc64/dev/ldc.c			ldc
+
+# Virtual disk
+device	vdsk: ldc, scsi
+attach	vdsk at cbus
+file	arch/sparc64/dev/vdsk.c			vdsk
Index: sys/arch/sparc64/sparc64/autoconf.c
===================================================================
RCS file: /cvsroot/src/sys/arch/sparc64/sparc64/autoconf.c,v
retrieving revision 1.207
diff -u -r1.207 autoconf.c
--- sys/arch/sparc64/sparc64/autoconf.c	16 Dec 2015 08:01:19 -0000	1.207
+++ sys/arch/sparc64/sparc64/autoconf.c	14 Aug 2016 19:19:27 -0000
@@ -93,6 +93,7 @@
 #include <machine/bootinfo.h>
 #include <sparc64/sparc64/cache.h>
 #include <sparc64/sparc64/timerreg.h>
+#include <sparc64/dev/cbusvar.h>
 
 #include <dev/ata/atavar.h>
 #include <dev/pci/pcivar.h>
@@ -980,6 +981,11 @@
 		dev_path_drive_match(dev, ofnode, adev->adev_channel*2+
 		    adev->adev_drv_data->drive, 0, 0);
 		return;
+	} else if (device_is_a(dev, "vdsk")) {
+		struct cbus_attach_args *ca = aux;
+		ofnode = ca->ca_node;
+		/* Ensure that the devices ofnode is stored for later use */
+		device_setofnode(dev, ofnode);
 	}
 
 	if (busdev == NULL)
@@ -1317,6 +1323,49 @@
 			}
 		}
 	}
+
+	if (CPU_ISSUN4V) {
+
+	  /*
+	   * Special sun4v handling in case the kernel is running in a 
+	   * secondary logical domain
+	   *
+	   * The bootpath looks something like this:
+	   *   /virtual-devices@100/channel-devices@200/disk@1:a
+	   *
+	   * The device hierarchy constructed during autoconfiguration is:
+	   *   mainbus/vbus/vdsk/scsibus/sd
+	   *
+	   * The logic to figure out the boot device is to look at the
+	   * grandparent to the 'sd' device and if this is a 'vdsk' device
+	   * and the ofnode matches the bootpaths ofnode then we have located
+	   * the boot device.
+	   */
+
+	  int ofnode;
+
+	  /* Cache the vdsk ofnode for later use later/below with sd device */  
+	  if (device_is_a(dev, "vdsk")) {
+	    ofnode = device_ofnode(dev);
+	    device_setofnode(dev, ofnode);
+	  }
+
+	  /* Examine if this is a sd device */  
+	  if (device_is_a(dev, "sd")) {
+	    device_t parent = device_parent(dev);
+	    device_t parent_parent = device_parent(parent);
+	    if (device_is_a(parent_parent, "vdsk")) {
+	      ofnode = device_ofnode(parent_parent);
+	      if (ofnode == ofbootpackage) {
+		booted_device = dev;
+		DPRINTF(ACDB_BOOTDEV, ("booted_device: %s\n", 
+				       device_xname(dev)));
+		return;
+	      }
+	    }
+	  }
+	}
+
 }
 
 static void