diff --git a/tools/testing/selftests/kselftest/runner.sh b/tools/testing/selftests/kselftest/runner.sh
index eff3ee303d0d6a5648acf335412637c4956f0c0e..00c9020bdda8b4f133807b0b6eb86f5ec90331e4 100644
--- a/tools/testing/selftests/kselftest/runner.sh
+++ b/tools/testing/selftests/kselftest/runner.sh
@@ -24,16 +24,6 @@ tap_prefix()
 	fi
 }
 
-# If stdbuf is unavailable, we must fall back to line-at-a-time piping.
-tap_unbuffer()
-{
-	if ! which stdbuf >/dev/null ; then
-		"$@"
-	else
-		stdbuf -i0 -o0 -e0 "$@"
-	fi
-}
-
 run_one()
 {
 	DIR="$1"
@@ -54,7 +44,7 @@ run_one()
 		echo "not ok $test_num $TEST_HDR_MSG"
 	else
 		cd `dirname $TEST` > /dev/null
-		(((((tap_unbuffer ./$BASENAME_TEST 2>&1; echo $? >&3) |
+		(((((./$BASENAME_TEST 2>&1; echo $? >&3) |
 			tap_prefix >&4) 3>&1) |
 			(read xs; exit $xs)) 4>>"$logfile" &&
 		echo "ok $test_num $TEST_HDR_MSG") ||
diff --git a/tools/testing/selftests/timers/adjtick.c b/tools/testing/selftests/timers/adjtick.c
index 0caca3a06bd26eebdff08ce7700aff14f58eb558..54d8d87f36b3ca628da694181bfd134039093a23 100644
--- a/tools/testing/selftests/timers/adjtick.c
+++ b/tools/testing/selftests/timers/adjtick.c
@@ -136,6 +136,7 @@ int check_tick_adj(long tickval)
 
 	eppm = get_ppm_drift();
 	printf("%lld usec, %lld ppm", systick + (systick * eppm / MILLION), eppm);
+	fflush(stdout);
 
 	tx1.modes = 0;
 	adjtimex(&tx1);
diff --git a/tools/testing/selftests/timers/leapcrash.c b/tools/testing/selftests/timers/leapcrash.c
index 830c462f605d9476b712f909db2a62c09e053959..dc80728ed1915551bf83c1ea855450d0ccc31c8a 100644
--- a/tools/testing/selftests/timers/leapcrash.c
+++ b/tools/testing/selftests/timers/leapcrash.c
@@ -101,6 +101,7 @@ int main(void)
 		}
 		clear_time_state();
 		printf(".");
+		fflush(stdout);
 	}
 	printf("[OK]\n");
 	return ksft_exit_pass();
diff --git a/tools/testing/selftests/timers/mqueue-lat.c b/tools/testing/selftests/timers/mqueue-lat.c
index 1867db5d6f5e0fcf9a9f494e54a570dc07aae0d6..7916cf5cc6fff189708caeb61804d25381b558dd 100644
--- a/tools/testing/selftests/timers/mqueue-lat.c
+++ b/tools/testing/selftests/timers/mqueue-lat.c
@@ -102,6 +102,7 @@ int main(int argc, char **argv)
 	int ret;
 
 	printf("Mqueue latency :                          ");
+	fflush(stdout);
 
 	ret = mqueue_lat_test();
 	if (ret < 0) {
diff --git a/tools/testing/selftests/timers/nanosleep.c b/tools/testing/selftests/timers/nanosleep.c
index 8adb0bb51d4da4a1ab4eddde5d15be21a5ffcfb1..71b5441c2fd9f6f3abb39a9c661556b3e5e13931 100644
--- a/tools/testing/selftests/timers/nanosleep.c
+++ b/tools/testing/selftests/timers/nanosleep.c
@@ -142,6 +142,7 @@ int main(int argc, char **argv)
 			continue;
 
 		printf("Nanosleep %-31s ", clockstring(clockid));
+		fflush(stdout);
 
 		length = 10;
 		while (length <= (NSEC_PER_SEC * 10)) {
diff --git a/tools/testing/selftests/timers/nsleep-lat.c b/tools/testing/selftests/timers/nsleep-lat.c
index c3c3dc10db17fe1493994fa2209bd06ce35b94fb..eb3e79ed7b4a9eb5b58b332490b51f1f2a0db204 100644
--- a/tools/testing/selftests/timers/nsleep-lat.c
+++ b/tools/testing/selftests/timers/nsleep-lat.c
@@ -155,6 +155,7 @@ int main(int argc, char **argv)
 			continue;
 
 		printf("nsleep latency %-26s ", clockstring(clockid));
+		fflush(stdout);
 
 		length = 10;
 		while (length <= (NSEC_PER_SEC * 10)) {
diff --git a/tools/testing/selftests/timers/raw_skew.c b/tools/testing/selftests/timers/raw_skew.c
index dcf73c5dab6e12e9074d15efae1ba9c65a139d60..b41d8dd0c40c564e8abd607fef00140b8a344b33 100644
--- a/tools/testing/selftests/timers/raw_skew.c
+++ b/tools/testing/selftests/timers/raw_skew.c
@@ -112,6 +112,7 @@ int main(int argv, char **argc)
 		printf("WARNING: ADJ_OFFSET in progress, this will cause inaccurate results\n");
 
 	printf("Estimating clock drift: ");
+	fflush(stdout);
 	sleep(120);
 
 	get_monotonic_and_raw(&mon, &raw);
diff --git a/tools/testing/selftests/timers/set-tai.c b/tools/testing/selftests/timers/set-tai.c
index 70fed27d8fd3cf8db9401542759ed53946e3e512..8c4179ee2ca294a48a4cd9686cbd9377f6434e3d 100644
--- a/tools/testing/selftests/timers/set-tai.c
+++ b/tools/testing/selftests/timers/set-tai.c
@@ -55,6 +55,7 @@ int main(int argc, char **argv)
 	printf("tai offset started at %i\n", ret);
 
 	printf("Checking tai offsets can be properly set: ");
+	fflush(stdout);
 	for (i = 1; i <= 60; i++) {
 		ret = set_tai(i);
 		ret = get_tai();
diff --git a/tools/testing/selftests/timers/set-tz.c b/tools/testing/selftests/timers/set-tz.c
index 877fd5532fee03ee9fe25bed1505fcedf78dde60..62bd33eb16f0a5754255c11651c11dc288550f52 100644
--- a/tools/testing/selftests/timers/set-tz.c
+++ b/tools/testing/selftests/timers/set-tz.c
@@ -65,6 +65,7 @@ int main(int argc, char **argv)
 	printf("tz_minuteswest started at %i, dst at %i\n", min, dst);
 
 	printf("Checking tz_minuteswest can be properly set: ");
+	fflush(stdout);
 	for (i = -15*60; i < 15*60; i += 30) {
 		ret = set_tz(i, dst);
 		ret = get_tz_min();
@@ -76,6 +77,7 @@ int main(int argc, char **argv)
 	printf("[OK]\n");
 
 	printf("Checking invalid tz_minuteswest values are caught: ");
+	fflush(stdout);
 
 	if (!set_tz(-15*60-1, dst)) {
 		printf("[FAILED] %i didn't return failure!\n", -15*60-1);
diff --git a/tools/testing/selftests/timers/threadtest.c b/tools/testing/selftests/timers/threadtest.c
index 759c9c06f1a034d4a566d81c1fb556f0c46bceff..cf3e48919874b3a1a23f8a10bb1e2fce5f9dfadd 100644
--- a/tools/testing/selftests/timers/threadtest.c
+++ b/tools/testing/selftests/timers/threadtest.c
@@ -163,6 +163,7 @@ int main(int argc, char **argv)
 	strftime(buf, 255, "%a, %d %b %Y %T %z", localtime(&start));
 	printf("%s\n", buf);
 	printf("Testing consistency with %i threads for %ld seconds: ", thread_count, runtime);
+	fflush(stdout);
 
 	/* spawn */
 	for (i = 0; i < thread_count; i++)
diff --git a/tools/testing/selftests/timers/valid-adjtimex.c b/tools/testing/selftests/timers/valid-adjtimex.c
index d9d3ab93b31a75a766bb8c1cbf8e30ce2c24bed3..5397de708d3c25bee1f9df965ea98ef1415cac16 100644
--- a/tools/testing/selftests/timers/valid-adjtimex.c
+++ b/tools/testing/selftests/timers/valid-adjtimex.c
@@ -123,6 +123,7 @@ int validate_freq(void)
 	/* Set the leap second insert flag */
 
 	printf("Testing ADJ_FREQ... ");
+	fflush(stdout);
 	for (i = 0; i < NUM_FREQ_VALID; i++) {
 		tx.modes = ADJ_FREQUENCY;
 		tx.freq = valid_freq[i];
@@ -250,6 +251,7 @@ int set_bad_offset(long sec, long usec, int use_nano)
 int validate_set_offset(void)
 {
 	printf("Testing ADJ_SETOFFSET... ");
+	fflush(stdout);
 
 	/* Test valid values */
 	if (set_offset(NSEC_PER_SEC - 1, 1))
diff --git a/tools/testing/selftests/x86/syscall_arg_fault.c b/tools/testing/selftests/x86/syscall_arg_fault.c
index 7db4fc9fa09feb970363ccb778252ce44bbd739c..d2548401921f1ea27918c606bc18d0fa7e046419 100644
--- a/tools/testing/selftests/x86/syscall_arg_fault.c
+++ b/tools/testing/selftests/x86/syscall_arg_fault.c
@@ -43,7 +43,7 @@ static sigjmp_buf jmpbuf;
 
 static volatile sig_atomic_t n_errs;
 
-static void sigsegv(int sig, siginfo_t *info, void *ctx_void)
+static void sigsegv_or_sigbus(int sig, siginfo_t *info, void *ctx_void)
 {
 	ucontext_t *ctx = (ucontext_t*)ctx_void;
 
@@ -73,7 +73,13 @@ int main()
 	if (sigaltstack(&stack, NULL) != 0)
 		err(1, "sigaltstack");
 
-	sethandler(SIGSEGV, sigsegv, SA_ONSTACK);
+	sethandler(SIGSEGV, sigsegv_or_sigbus, SA_ONSTACK);
+	/*
+	 * The actual exception can vary.  On Atom CPUs, we get #SS
+	 * instead of #PF when the vDSO fails to access the stack when
+	 * ESP is too close to 2^32, and #SS causes SIGBUS.
+	 */
+	sethandler(SIGBUS, sigsegv_or_sigbus, SA_ONSTACK);
 	sethandler(SIGILL, sigill, SA_ONSTACK);
 
 	/*