*** NO COMMENTS ***

@@ -285,10 +285,11 @@
 }
 
 void
 ddt_phys_fill(ddt_phys_t *ddp, const blkptr_t *bp)
 {
+        ASSERT(ddp != NULL);
         ASSERT(ddp->ddp_phys_birth == 0);
 
         for (int d = 0; d < SPA_DVAS_PER_BP; d++)
                 ddp->ddp_dva[d] = bp->blk_dva[d];
         ddp->ddp_phys_birth = BP_PHYSICAL_BIRTH(bp);

@@ -295,24 +296,33 @@
 }
 
 void
 ddt_phys_clear(ddt_phys_t *ddp)
 {
+        ASSERT(ddp != NULL);
+        if (ddp) {
         bzero(ddp, sizeof (*ddp));
+        }
 }
 
 void
 ddt_phys_addref(ddt_phys_t *ddp)
 {
+        ASSERT(ddp != NULL);
+        if (ddp) {
         ddp->ddp_refcnt++;
+        }
 }
 
 void
 ddt_phys_decref(ddt_phys_t *ddp)
 {
+//      ASSERT(ddp != NULL);
+        if (ddp) {
         ASSERT((int64_t)ddp->ddp_refcnt > 0);
         ddp->ddp_refcnt--;
+        }
 }
 
 void
 ddt_phys_free(ddt_t *ddt, ddt_key_t *ddk, ddt_phys_t *ddp, uint64_t txg)
 {

@@ -331,10 +341,17 @@
         for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
                 if (DVA_EQUAL(BP_IDENTITY(bp), &ddp->ddp_dva[0]) &&
                     BP_PHYSICAL_BIRTH(bp) == ddp->ddp_phys_birth)
                         return (ddp);
         }
+        (void) printf("ddt_phys_select() found nothing for "
+            "DVA[BP]=<%llu:%llx:%llx> and phys_birth[BP]=%llu\n",
+            (u_longlong_t)DVA_GET_VDEV(BP_IDENTITY(bp)),
+            (u_longlong_t)DVA_GET_OFFSET(BP_IDENTITY(bp)),
+            (u_longlong_t)DVA_GET_ASIZE(BP_IDENTITY(bp)),
+            (u_longlong_t)BP_PHYSICAL_BIRTH(bp)
+        );
         return (NULL);
 }
 
 uint64_t
 ddt_phys_total_refcnt(const ddt_entry_t *dde)