diff --git a/memcheck/tests/supp_unknown.stderr.exp b/memcheck/tests/supp_unknown.stderr.exp
index 8a8d02f49..8f87de722 100644
--- a/memcheck/tests/supp_unknown.stderr.exp
+++ b/memcheck/tests/supp_unknown.stderr.exp
@@ -2,6 +2,7 @@
 Process terminating with default action of signal 11 (SIGSEGV)
  Access not within mapped region at address 0x........
    ...
+   by 0x........: main (badjump.c:17)
  If you believe this happened as a result of a stack
  overflow in your program's main thread (unlikely but
  possible), you can try to increase the size of the
diff --git a/memcheck/tests/supp_unknown.stderr.exp-s390x b/memcheck/tests/supp_unknown.stderr.exp-kfail
similarity index 86%
rename from memcheck/tests/supp_unknown.stderr.exp-s390x
rename to memcheck/tests/supp_unknown.stderr.exp-kfail
index 5adcfa64d..8a8d02f49 100644
--- a/memcheck/tests/supp_unknown.stderr.exp-s390x
+++ b/memcheck/tests/supp_unknown.stderr.exp-kfail
@@ -1,8 +1,7 @@
 
 Process terminating with default action of signal 11 (SIGSEGV)
  Access not within mapped region at address 0x........
-   at 0x........: ???
-   by 0x........: main (badjump.c:17)
+   ...
  If you believe this happened as a result of a stack
  overflow in your program's main thread (unlikely but
  possible), you can try to increase the size of the
diff --git a/memcheck/tests/supp_unknown.vgtest b/memcheck/tests/supp_unknown.vgtest
index de687e653..50d71b772 100644
--- a/memcheck/tests/supp_unknown.vgtest
+++ b/memcheck/tests/supp_unknown.vgtest
@@ -1,3 +1,4 @@
 vgopts: -q --suppressions=supp_unknown.supp
 prog: badjump
 cleanup: rm -f vgcore.pid*
+stderr_filter_args: badjump.c