diff --git a/sys/cddl/dev/systrace/systrace.c b/sys/cddl/dev/systrace/systrace.c
index cc48747..31c11c2 100644
--- a/sys/cddl/dev/systrace/systrace.c
+++ b/sys/cddl/dev/systrace/systrace.c
@@ -220,8 +220,12 @@ systrace_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *des
 {
 	int sysnum = SYSTRACE_SYSNUM((uintptr_t)parg);
 
-	systrace_setargdesc(sysnum, desc->dtargd_ndx, desc->dtargd_native,
-	    sizeof(desc->dtargd_native));
+	if (SYSTRACE_ISENTRY((uintptr_t)parg))
+		systrace_entry_setargdesc(sysnum, desc->dtargd_ndx, 
+		    desc->dtargd_native, sizeof(desc->dtargd_native));
+	else
+		systrace_return_setargdesc(sysnum, desc->dtargd_ndx, 
+		    desc->dtargd_native, sizeof(desc->dtargd_native));
 
 	if (desc->dtargd_native[0] == '\0')
 		desc->dtargd_ndx = DTRACE_ARGNONE;
diff --git a/sys/kern/makesyscalls.sh b/sys/kern/makesyscalls.sh
index d1162b5..1f081ce 100644
--- a/sys/kern/makesyscalls.sh
+++ b/sys/kern/makesyscalls.sh
@@ -38,6 +38,7 @@ sysinc="sysinc.switch.$$"
 sysarg="sysarg.switch.$$"
 sysprotoend="sysprotoend.$$"
 systracetmp="systrace.$$"
+systraceret="systraceret.$$"
 
 if [ -r capabilities.conf ]; then
 	capenabled=`cat capabilities.conf | grep -v "^#" | grep -v "^$"`
@@ -46,9 +47,9 @@ else
 	capenabled=""
 fi
 
-trap "rm $sysaue $sysdcl $syscompat $syscompatdcl $syscompat4 $syscompat4dcl $syscompat6 $syscompat6dcl $syscompat7 $syscompat7dcl $sysent $sysinc $sysarg $sysprotoend $systracetmp" 0
+trap "rm $sysaue $sysdcl $syscompat $syscompatdcl $syscompat4 $syscompat4dcl $syscompat6 $syscompat6dcl $syscompat7 $syscompat7dcl $sysent $sysinc $sysarg $sysprotoend $systracetmp $systraceret" 0
 
-touch $sysaue $sysdcl $syscompat $syscompatdcl $syscompat4 $syscompat4dcl $syscompat6 $syscompat6dcl $syscompat7 $syscompat7dcl $sysent $sysinc $sysarg $sysprotoend $systracetmp
+touch $sysaue $sysdcl $syscompat $syscompatdcl $syscompat4 $syscompat4dcl $syscompat6 $syscompat6dcl $syscompat7 $syscompat7dcl $sysent $sysinc $sysarg $sysprotoend $systracetmp $systraceret
 
 case $# in
     0)	echo "usage: $0 input-file <config-file>" 1>&2
@@ -96,6 +97,7 @@ s/\$//g
 		sysmk = \"$sysmk\"
 		systrace = \"$systrace\"
 		systracetmp = \"$systracetmp\"
+		systraceret = \"$systraceret\"
 		compat = \"$compat\"
 		compat4 = \"$compat4\"
 		compat6 = \"$compat6\"
@@ -179,9 +181,12 @@ s/\$//g
 		printf "\tint64_t *iarg  = (int64_t *) uarg;\n" > systrace
 		printf "\tswitch (sysnum) {\n" > systrace
 
-		printf "static void\nsystrace_setargdesc(int sysnum, int ndx, char *desc, size_t descsz)\n{\n\tconst char *p = NULL;\n" > systracetmp
+		printf "static void\nsystrace_entry_setargdesc(int sysnum, int ndx, char *desc, size_t descsz)\n{\n\tconst char *p = NULL;\n" > systracetmp
 		printf "\tswitch (sysnum) {\n" > systracetmp
 
+		printf "static void\nsystrace_return_setargdesc(int sysnum, int ndx, char *desc, size_t descsz)\n{\n\tconst char *p = NULL;\n" > systraceret
+		printf "\tswitch (sysnum) {\n" > systraceret
+
 		next
 	}
 	NF == 0 || $1 ~ /^;/ {
@@ -202,6 +207,7 @@ s/\$//g
 		print > sysnames
 		print > systrace
 		print > systracetmp
+		print > systraceret
 		savesyscall = syscall
 		next
 	}
@@ -216,6 +222,7 @@ s/\$//g
 		print > sysnames
 		print > systrace
 		print > systracetmp
+		print > systraceret
 		syscall = savesyscall
 		next
 	}
@@ -230,6 +237,7 @@ s/\$//g
 		print > sysnames
 		print > systrace
 		print > systracetmp
+		print > systraceret
 		next
 	}
 	syscall != $1 {
@@ -303,7 +311,8 @@ s/\$//g
 			parserr($end, ")")
 		end--
 
-		f++	#function return type
+		syscallret=$f
+		f++
 
 		funcname=$f
 
@@ -387,6 +396,7 @@ s/\$//g
 		parseline()
 		printf("\t/* %s */\n\tcase %d: {\n", funcname, syscall) > systrace
 		printf("\t/* %s */\n\tcase %d:\n", funcname, syscall) > systracetmp
+		printf("\t/* %s */\n\tcase %d:\n", funcname, syscall) > systraceret
 		if (argc > 0) {
 			printf("\t\tswitch(ndx) {\n") > systracetmp
 			printf("\t\tstruct %s *p = params;\n", argalias) > systrace
@@ -406,6 +416,10 @@ s/\$//g
 					     argname[i], argtype[i]) > systrace
 			}
 			printf("\t\tdefault:\n\t\t\tbreak;\n\t\t};\n") > systracetmp
+
+			printf("\t\tif (ndx == 0 || ndx == 1)\n") > systraceret
+			printf("\t\t\tp = \"%s\";\n", syscallret) > systraceret
+			printf("\t\tbreak;\n") > systraceret
 		}
 		printf("\t\t*n_args = %d;\n\t\tbreak;\n\t}\n", argc) > systrace
 		printf("\t\tbreak;\n") > systracetmp
@@ -623,6 +637,7 @@ s/\$//g
 		    > syshdr
 		printf "\tdefault:\n\t\t*n_args = 0;\n\t\tbreak;\n\t};\n}\n" > systrace
 		printf "\tdefault:\n\t\tbreak;\n\t};\n\tif (p != NULL)\n\t\tstrlcpy(desc, p, descsz);\n}\n" > systracetmp
+		printf "\tdefault:\n\t\tbreak;\n\t};\n\tif (p != NULL)\n\t\tstrlcpy(desc, p, descsz);\n}\n" > systraceret
 	} '
 
 cat $sysinc $sysent >> $syssw
@@ -633,4 +648,5 @@ cat $sysarg $sysdcl \
 	$syscompat7 $syscompat7dcl \
 	$sysaue $sysprotoend > $sysproto
 cat $systracetmp >> $systrace
+cat $systraceret >> $systrace