diff --git a/Makefile b/Makefile
index 64cbc66cebca..9a70578922d3 100644
--- a/Makefile
+++ b/Makefile
@@ -1172,11 +1172,11 @@ headers_check: headers_install
 
 PHONY += kselftest
 kselftest:
-	$(Q)$(MAKE) -C tools/testing/selftests run_tests
+	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
 
 PHONY += kselftest-clean
 kselftest-clean:
-	$(Q)$(MAKE) -C tools/testing/selftests clean
+	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests clean
 
 PHONY += kselftest-merge
 kselftest-merge:
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 26ce4f7168be..ff805643b5f7 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -52,6 +52,10 @@ override LDFLAGS =
 override MAKEFLAGS =
 endif
 
+ifneq ($(KBUILD_SRC),)
+override LDFLAGS =
+endif
+
 BUILD := $(O)
 ifndef BUILD
   BUILD := $(KBUILD_OUTPUT)
@@ -62,32 +66,32 @@ endif
 
 export BUILD
 all:
-	for TARGET in $(TARGETS); do		\
+	@for TARGET in $(TARGETS); do		\
 		BUILD_TARGET=$$BUILD/$$TARGET;	\
 		mkdir $$BUILD_TARGET  -p;	\
 		make OUTPUT=$$BUILD_TARGET -C $$TARGET;\
 	done;
 
 run_tests: all
-	for TARGET in $(TARGETS); do \
+	@for TARGET in $(TARGETS); do \
 		BUILD_TARGET=$$BUILD/$$TARGET;	\
 		make OUTPUT=$$BUILD_TARGET -C $$TARGET run_tests;\
 	done;
 
 hotplug:
-	for TARGET in $(TARGETS_HOTPLUG); do \
+	@for TARGET in $(TARGETS_HOTPLUG); do \
 		BUILD_TARGET=$$BUILD/$$TARGET;	\
 		make OUTPUT=$$BUILD_TARGET -C $$TARGET;\
 	done;
 
 run_hotplug: hotplug
-	for TARGET in $(TARGETS_HOTPLUG); do \
+	@for TARGET in $(TARGETS_HOTPLUG); do \
 		BUILD_TARGET=$$BUILD/$$TARGET;	\
 		make OUTPUT=$$BUILD_TARGET -C $$TARGET run_full_test;\
 	done;
 
 clean_hotplug:
-	for TARGET in $(TARGETS_HOTPLUG); do \
+	@for TARGET in $(TARGETS_HOTPLUG); do \
 		BUILD_TARGET=$$BUILD/$$TARGET;	\
 		make OUTPUT=$$BUILD_TARGET -C $$TARGET clean;\
 	done;
@@ -103,7 +107,7 @@ install:
 ifdef INSTALL_PATH
 	@# Ask all targets to install their files
 	mkdir -p $(INSTALL_PATH)
-	for TARGET in $(TARGETS); do \
+	@for TARGET in $(TARGETS); do \
 		BUILD_TARGET=$$BUILD/$$TARGET;	\
 		make OUTPUT=$$BUILD_TARGET -C $$TARGET INSTALL_PATH=$(INSTALL_PATH)/$$TARGET install; \
 	done;
@@ -128,7 +132,7 @@ else
 endif
 
 clean:
-	for TARGET in $(TARGETS); do \
+	@for TARGET in $(TARGETS); do \
 		BUILD_TARGET=$$BUILD/$$TARGET;	\
 		make OUTPUT=$$BUILD_TARGET -C $$TARGET clean;\
 	done;
diff --git a/tools/testing/selftests/bpf/bpf_util.h b/tools/testing/selftests/bpf/bpf_util.h
index 20ecbaa0d85d..6c53a8906eff 100644
--- a/tools/testing/selftests/bpf/bpf_util.h
+++ b/tools/testing/selftests/bpf/bpf_util.h
@@ -12,6 +12,7 @@ static inline unsigned int bpf_num_possible_cpus(void)
 	unsigned int start, end, possible_cpus = 0;
 	char buff[128];
 	FILE *fp;
+	int n;
 
 	fp = fopen(fcpu, "r");
 	if (!fp) {
@@ -20,17 +21,17 @@ static inline unsigned int bpf_num_possible_cpus(void)
 	}
 
 	while (fgets(buff, sizeof(buff), fp)) {
-		if (sscanf(buff, "%u-%u", &start, &end) == 2) {
-			possible_cpus = start == 0 ? end + 1 : 0;
-			break;
+		n = sscanf(buff, "%u-%u", &start, &end);
+		if (n == 0) {
+			printf("Failed to retrieve # possible CPUs!\n");
+			exit(1);
+		} else if (n == 1) {
+			end = start;
 		}
+		possible_cpus = start == 0 ? end + 1 : 0;
+		break;
 	}
-
 	fclose(fp);
-	if (!possible_cpus) {
-		printf("Failed to retrieve # possible CPUs!\n");
-		exit(1);
-	}
 
 	return possible_cpus;
 }
diff --git a/tools/testing/selftests/breakpoints/Makefile b/tools/testing/selftests/breakpoints/Makefile
index 6b214b7b10fb..247b0a1899d7 100644
--- a/tools/testing/selftests/breakpoints/Makefile
+++ b/tools/testing/selftests/breakpoints/Makefile
@@ -2,14 +2,14 @@
 uname_M := $(shell uname -m 2>/dev/null || echo not)
 ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/x86/ -e s/x86_64/x86/)
 
+TEST_GEN_PROGS := step_after_suspend_test
+
 ifeq ($(ARCH),x86)
-TEST_GEN_PROGS := breakpoint_test
+TEST_GEN_PROGS += breakpoint_test
 endif
 ifneq (,$(filter $(ARCH),aarch64 arm64))
-TEST_GEN_PROGS := breakpoint_test_arm64
+TEST_GEN_PROGS += breakpoint_test_arm64
 endif
 
-TEST_GEN_PROGS += step_after_suspend_test
-
 include ../lib.mk
 
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
index 2a1cb9908746..a4fd4c851a5b 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/multiple_kprobes.tc
@@ -1,6 +1,8 @@
 #!/bin/sh
 # description: Register/unregister many kprobe events
 
+[ -f kprobe_events ] || exit_unsupported # this is configurable
+
 # ftrace fentry skip size depends on the machine architecture.
 # Currently HAVE_KPROBES_ON_FTRACE defined on x86 and powerpc64le
 case `uname -m` in
diff --git a/tools/testing/selftests/futex/Makefile b/tools/testing/selftests/futex/Makefile
index 7c647f619d63..f0c0369ccb79 100644
--- a/tools/testing/selftests/futex/Makefile
+++ b/tools/testing/selftests/futex/Makefile
@@ -7,14 +7,17 @@ TEST_PROGS := run.sh
 include ../lib.mk
 
 all:
-	for DIR in $(SUBDIRS); do		\
+	@for DIR in $(SUBDIRS); do		\
 		BUILD_TARGET=$(OUTPUT)/$$DIR;	\
 		mkdir $$BUILD_TARGET  -p;	\
 		make OUTPUT=$$BUILD_TARGET -C $$DIR $@;\
+		if [ -e $$DIR/$(TEST_PROGS) ]; then
+			rsync -a $$DIR/$(TEST_PROGS) $$BUILD_TARGET/;
+		fi
 	done
 
 override define RUN_TESTS
-	$(OUTPUT)/run.sh
+	@cd $(OUTPUT); ./run.sh
 endef
 
 override define INSTALL_RULE
@@ -33,7 +36,7 @@ override define EMIT_TESTS
 endef
 
 override define CLEAN
-	for DIR in $(SUBDIRS); do		\
+	@for DIR in $(SUBDIRS); do		\
 		BUILD_TARGET=$(OUTPUT)/$$DIR;	\
 		mkdir $$BUILD_TARGET  -p;	\
 		make OUTPUT=$$BUILD_TARGET -C $$DIR $@;\
diff --git a/tools/testing/selftests/intel_pstate/Makefile b/tools/testing/selftests/intel_pstate/Makefile
index 849a90ffe8dd..a97e24edde39 100644
--- a/tools/testing/selftests/intel_pstate/Makefile
+++ b/tools/testing/selftests/intel_pstate/Makefile
@@ -1,7 +1,9 @@
 CFLAGS := $(CFLAGS) -Wall -D_GNU_SOURCE
 LDLIBS := $(LDLIBS) -lm
 
+ifeq (,$(filter $(ARCH),x86))
 TEST_GEN_FILES := msr aperf
+endif
 
 TEST_PROGS := run.sh
 
diff --git a/tools/testing/selftests/intel_pstate/run.sh b/tools/testing/selftests/intel_pstate/run.sh
index 7868c106b8b1..d3ab48f91cd6 100755
--- a/tools/testing/selftests/intel_pstate/run.sh
+++ b/tools/testing/selftests/intel_pstate/run.sh
@@ -29,13 +29,12 @@
 
 EVALUATE_ONLY=0
 
-max_cpus=$(($(nproc)-1))
+if ! uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ | grep -q x86; then
+	echo "$0 # Skipped: Test can only run on x86 architectures."
+	exit 0
+fi
 
-# compile programs
-gcc aperf.c -Wall -D_GNU_SOURCE -o aperf  -lm
-[ $? -ne 0 ] && echo "Problem compiling aperf.c." && exit 1
-gcc -o msr msr.c -lm
-[ $? -ne 0 ] && echo "Problem compiling msr.c." && exit 1
+max_cpus=$(($(nproc)-1))
 
 function run_test () {
 
diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk
index 693616651da5..f65886af7c0c 100644
--- a/tools/testing/selftests/lib.mk
+++ b/tools/testing/selftests/lib.mk
@@ -6,7 +6,14 @@ ifeq (0,$(MAKELEVEL))
 OUTPUT := $(shell pwd)
 endif
 
+# The following are built by lib.mk common compile rules.
+# TEST_CUSTOM_PROGS should be used by tests that require
+# custom build rule and prevent common build rule use.
+# TEST_PROGS are for test shell scripts.
+# TEST_CUSTOM_PROGS and TEST_PROGS will be run by common run_tests
+# and install targets. Common clean doesn't touch them.
 TEST_GEN_PROGS := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_PROGS))
+TEST_GEN_PROGS_EXTENDED := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_PROGS_EXTENDED))
 TEST_GEN_FILES := $(patsubst %,$(OUTPUT)/%,$(TEST_GEN_FILES))
 
 all: $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES)
@@ -20,17 +27,28 @@ define RUN_TESTS
 		test_num=`echo $$test_num+1 | bc`;	\
 		echo "selftests: $$BASENAME_TEST";	\
 		echo "========================================";	\
-		if [ ! -x $$BASENAME_TEST ]; then	\
+		if [ ! -x $$TEST ]; then	\
 			echo "selftests: Warning: file $$BASENAME_TEST is not executable, correct this.";\
 			echo "not ok 1..$$test_num selftests: $$BASENAME_TEST [FAIL]"; \
 		else					\
-			cd `dirname $$TEST` > /dev/null; (./$$BASENAME_TEST && echo "ok 1..$$test_num selftests: $$BASENAME_TEST [PASS]") || echo "not ok 1..$$test_num selftests:  $$BASENAME_TEST [FAIL]"; cd - > /dev/null;\
+			cd `dirname $$TEST` > /dev/null; (./$$BASENAME_TEST > /tmp/$$BASENAME_TEST 2>&1 && echo "ok 1..$$test_num selftests: $$BASENAME_TEST [PASS]") || echo "not ok 1..$$test_num selftests:  $$BASENAME_TEST [FAIL]"; cd - > /dev/null;\
 		fi;					\
 	done;
 endef
 
 run_tests: all
-	$(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_PROGS))
+ifneq ($(KBUILD_SRC),)
+	@if [ "X$(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES)" != "X" ]; then
+		@rsync -aq $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(OUTPUT)
+	fi
+	@if [ "X$(TEST_PROGS)" != "X" ]; then
+		$(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(OUTPUT)/$(TEST_PROGS))
+	else
+		$(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS))
+	fi
+else
+	$(call RUN_TESTS, $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(TEST_PROGS))
+endif
 
 define INSTALL_RULE
 	@if [ "X$(TEST_PROGS)$(TEST_PROGS_EXTENDED)$(TEST_FILES)" != "X" ]; then					\
@@ -38,10 +56,10 @@ define INSTALL_RULE
 		echo "rsync -a $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(INSTALL_PATH)/";	\
 		rsync -a $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES) $(INSTALL_PATH)/;		\
 	fi
-	@if [ "X$(TEST_GEN_PROGS)$(TEST_GEN_PROGS_EXTENDED)$(TEST_GEN_FILES)" != "X" ]; then					\
+	@if [ "X$(TEST_GEN_PROGS)$(TEST_CUSTOM_PROGS)$(TEST_GEN_PROGS_EXTENDED)$(TEST_GEN_FILES)" != "X" ]; then					\
 		mkdir -p ${INSTALL_PATH};										\
-		echo "rsync -a $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(INSTALL_PATH)/";	\
-		rsync -a $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(INSTALL_PATH)/;		\
+		echo "rsync -a $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(INSTALL_PATH)/";	\
+		rsync -a $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(INSTALL_PATH)/;		\
 	fi
 endef
 
@@ -53,15 +71,20 @@ else
 endif
 
 define EMIT_TESTS
-	@for TEST in $(TEST_GEN_PROGS) $(TEST_PROGS); do \
+	@for TEST in $(TEST_GEN_PROGS) $(TEST_CUSTOM_PROGS) $(TEST_PROGS); do \
 		BASENAME_TEST=`basename $$TEST`;	\
-		echo "(./$$BASENAME_TEST && echo \"selftests: $$BASENAME_TEST [PASS]\") || echo \"selftests: $$BASENAME_TEST [FAIL]\""; \
+		echo "(./$$BASENAME_TEST > /tmp/$$BASENAME_TEST 2>&1 && echo \"selftests: $$BASENAME_TEST [PASS]\") || echo \"selftests: $$BASENAME_TEST [FAIL]\""; \
 	done;
 endef
 
 emit_tests:
 	$(EMIT_TESTS)
 
+# define if isn't already. It is undefined in make O= case.
+ifeq ($(RM),)
+RM := rm -f
+endif
+
 define CLEAN
 	$(RM) -r $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED) $(TEST_GEN_FILES) $(EXTRA_CLEAN)
 endef
@@ -69,6 +92,15 @@ endef
 clean:
 	$(CLEAN)
 
+# When make O= with kselftest target from main level
+# the following aren't defined.
+#
+ifneq ($(KBUILD_SRC),)
+LINK.c = $(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH)
+COMPILE.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c
+LINK.S = $(CC) $(ASFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH)
+endif
+
 $(OUTPUT)/%:%.c
 	$(LINK.c) $^ $(LDLIBS) -o $@
 
diff --git a/tools/testing/selftests/memfd/run_tests.sh b/tools/testing/selftests/memfd/run_tests.sh
old mode 100644
new mode 100755
diff --git a/tools/testing/selftests/mqueue/Makefile b/tools/testing/selftests/mqueue/Makefile
index 79a664aeb8d7..0f5e347b068d 100644
--- a/tools/testing/selftests/mqueue/Makefile
+++ b/tools/testing/selftests/mqueue/Makefile
@@ -5,8 +5,8 @@ TEST_GEN_PROGS := mq_open_tests mq_perf_tests
 include ../lib.mk
 
 override define RUN_TESTS
-	@./mq_open_tests /test1 || echo "selftests: mq_open_tests [FAIL]"
-	@./mq_perf_tests || echo "selftests: mq_perf_tests [FAIL]"
+	$(OUTPUT)/mq_open_tests /test1 || echo "selftests: mq_open_tests [FAIL]"
+	$(OUTPUT)//mq_perf_tests || echo "selftests: mq_perf_tests [FAIL]"
 endef
 
 override define EMIT_TESTS
diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore
index 9801253e4802..c612d6e38c62 100644
--- a/tools/testing/selftests/net/.gitignore
+++ b/tools/testing/selftests/net/.gitignore
@@ -6,3 +6,4 @@ reuseport_bpf
 reuseport_bpf_cpu
 reuseport_bpf_numa
 reuseport_dualstack
+reuseaddr_conflict
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index de1f5772b878..d86bca991f45 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -5,9 +5,9 @@ CFLAGS += -I../../../../usr/include/
 
 TEST_PROGS := run_netsocktests run_afpackettests test_bpf.sh netdevice.sh rtnetlink.sh
 TEST_GEN_FILES =  socket
-TEST_GEN_FILES += psock_fanout psock_tpacket
-TEST_GEN_FILES += reuseport_bpf reuseport_bpf_cpu reuseport_bpf_numa
-TEST_GEN_FILES += reuseport_dualstack msg_zerocopy
+TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy
+TEST_GEN_PROGS = reuseport_bpf reuseport_bpf_cpu reuseport_bpf_numa
+TEST_GEN_PROGS += reuseport_dualstack reuseaddr_conflict
 
 include ../lib.mk
 
diff --git a/tools/testing/selftests/net/msg_zerocopy.c b/tools/testing/selftests/net/msg_zerocopy.c
index 40232af5b023..3ab6ec403905 100644
--- a/tools/testing/selftests/net/msg_zerocopy.c
+++ b/tools/testing/selftests/net/msg_zerocopy.c
@@ -55,7 +55,7 @@
 #include <unistd.h>
 
 #ifndef SO_EE_ORIGIN_ZEROCOPY
-#define SO_EE_ORIGIN_ZEROCOPY		SO_EE_ORIGIN_UPAGE
+#define SO_EE_ORIGIN_ZEROCOPY		5
 #endif
 
 #ifndef SO_ZEROCOPY
diff --git a/tools/testing/selftests/net/netdevice.sh b/tools/testing/selftests/net/netdevice.sh
index 4e00568d70c2..90cb903c3381 100755
--- a/tools/testing/selftests/net/netdevice.sh
+++ b/tools/testing/selftests/net/netdevice.sh
@@ -178,7 +178,7 @@ if [ "$(id -u)" -ne 0 ];then
 	exit 0
 fi
 
-ip -Version 2>/dev/null >/dev/null
+ip link show 2>/dev/null >/dev/null
 if [ $? -ne 0 ];then
 	echo "SKIP: Could not run test without the ip tool"
 	exit 0
diff --git a/tools/testing/selftests/net/reuseaddr_conflict.c b/tools/testing/selftests/net/reuseaddr_conflict.c
new file mode 100644
index 000000000000..7c5b12664b03
--- /dev/null
+++ b/tools/testing/selftests/net/reuseaddr_conflict.c
@@ -0,0 +1,114 @@
+/*
+ * Test for the regression introduced by
+ *
+ * b9470c27607b ("inet: kill smallest_size and smallest_port")
+ *
+ * If we open an ipv4 socket on a port with reuseaddr we shouldn't reset the tb
+ * when we open the ipv6 conterpart, which is what was happening previously.
+ */
+#include <errno.h>
+#include <error.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#define PORT 9999
+
+int open_port(int ipv6, int any)
+{
+	int fd = -1;
+	int reuseaddr = 1;
+	int v6only = 1;
+	int addrlen;
+	int ret = -1;
+	struct sockaddr *addr;
+	int family = ipv6 ? AF_INET6 : AF_INET;
+
+	struct sockaddr_in6 addr6 = {
+		.sin6_family = AF_INET6,
+		.sin6_port = htons(PORT),
+		.sin6_addr = in6addr_any
+	};
+	struct sockaddr_in addr4 = {
+		.sin_family = AF_INET,
+		.sin_port = htons(PORT),
+		.sin_addr.s_addr = any ? htonl(INADDR_ANY) : inet_addr("127.0.0.1"),
+	};
+
+
+	if (ipv6) {
+		addr = (struct sockaddr*)&addr6;
+		addrlen = sizeof(addr6);
+	} else {
+		addr = (struct sockaddr*)&addr4;
+		addrlen = sizeof(addr4);
+	}
+
+	if ((fd = socket(family, SOCK_STREAM, IPPROTO_TCP)) < 0) {
+		perror("socket");
+		goto out;
+	}
+
+	if (ipv6 && setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, (void*)&v6only,
+			       sizeof(v6only)) < 0) {
+		perror("setsockopt IPV6_V6ONLY");
+		goto out;
+	}
+
+	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &reuseaddr,
+		       sizeof(reuseaddr)) < 0) {
+		perror("setsockopt SO_REUSEADDR");
+		goto out;
+	}
+
+	if (bind(fd, addr, addrlen) < 0) {
+		perror("bind");
+		goto out;
+	}
+
+	if (any)
+		return fd;
+
+	if (listen(fd, 1) < 0) {
+		perror("listen");
+		goto out;
+	}
+	return fd;
+out:
+	close(fd);
+	return ret;
+}
+
+int main(void)
+{
+	int listenfd;
+	int fd1, fd2;
+
+	fprintf(stderr, "Opening 127.0.0.1:%d\n", PORT);
+	listenfd = open_port(0, 0);
+	if (listenfd < 0)
+		error(1, errno, "Couldn't open listen socket");
+	fprintf(stderr, "Opening INADDR_ANY:%d\n", PORT);
+	fd1 = open_port(0, 1);
+	if (fd1 >= 0)
+		error(1, 0, "Was allowed to create an ipv4 reuseport on a already bound non-reuseport socket");
+	fprintf(stderr, "Opening in6addr_any:%d\n", PORT);
+	fd1 = open_port(1, 1);
+	if (fd1 < 0)
+		error(1, errno, "Couldn't open ipv6 reuseport");
+	fprintf(stderr, "Opening INADDR_ANY:%d\n", PORT);
+	fd2 = open_port(0, 1);
+	if (fd2 >= 0)
+		error(1, 0, "Was allowed to create an ipv4 reuseport on a already bound non-reuseport socket");
+	close(fd1);
+	fprintf(stderr, "Opening INADDR_ANY:%d after closing ipv6 socket\n", PORT);
+	fd1 = open_port(0, 1);
+	if (fd1 >= 0)
+		error(1, 0, "Was allowed to create an ipv4 reuseport on an already bound non-reuseport socket with no ipv6");
+	fprintf(stderr, "Success");
+	return 0;
+}
diff --git a/tools/testing/selftests/seccomp/seccomp_bpf.c b/tools/testing/selftests/seccomp/seccomp_bpf.c
index 4d6f92a9df6b..19cd272c234d 100644
--- a/tools/testing/selftests/seccomp/seccomp_bpf.c
+++ b/tools/testing/selftests/seccomp/seccomp_bpf.c
@@ -6,10 +6,18 @@
  */
 
 #include <sys/types.h>
-#include <asm/siginfo.h>
-#define __have_siginfo_t 1
-#define __have_sigval_t 1
-#define __have_sigevent_t 1
+
+/*
+ * glibc 2.26 and later have SIGSYS in siginfo_t. Before that,
+ * we need to use the kernel's siginfo.h file and trick glibc
+ * into accepting it.
+ */
+#if !__GLIBC_PREREQ(2, 26)
+# include <asm/siginfo.h>
+# define __have_siginfo_t 1
+# define __have_sigval_t 1
+# define __have_sigevent_t 1
+#endif
 
 #include <errno.h>
 #include <linux/filter.h>
@@ -676,7 +684,7 @@ TEST_F_SIGNAL(TRAP, ign, SIGSYS)
 	syscall(__NR_getpid);
 }
 
-static struct siginfo TRAP_info;
+static siginfo_t TRAP_info;
 static volatile int TRAP_nr;
 static void TRAP_action(int nr, siginfo_t *info, void *void_context)
 {
diff --git a/tools/testing/selftests/sigaltstack/sas.c b/tools/testing/selftests/sigaltstack/sas.c
index 7d406c3973ba..97bb150837df 100644
--- a/tools/testing/selftests/sigaltstack/sas.c
+++ b/tools/testing/selftests/sigaltstack/sas.c
@@ -39,7 +39,11 @@ void my_usr1(int sig, siginfo_t *si, void *u)
 	stack_t stk;
 	struct stk_data *p;
 
+#if __s390x__
+	register unsigned long sp asm("%15");
+#else
 	register unsigned long sp asm("sp");
+#endif
 
 	if (sp < (unsigned long)sstack ||
 			sp >= (unsigned long)sstack + SIGSTKSZ) {
diff --git a/tools/testing/selftests/sync/Makefile b/tools/testing/selftests/sync/Makefile
index 4981c6b6d050..8e04d0afcbd7 100644
--- a/tools/testing/selftests/sync/Makefile
+++ b/tools/testing/selftests/sync/Makefile
@@ -2,12 +2,16 @@ CFLAGS += -O2 -g -std=gnu89 -pthread -Wall -Wextra
 CFLAGS += -I../../../../usr/include/
 LDFLAGS += -pthread
 
-TEST_PROGS = sync_test
-
-all: $(TEST_PROGS)
+.PHONY: all clean
 
 include ../lib.mk
 
+# lib.mk TEST_CUSTOM_PROGS var is for custom tests that need special
+# build rules. lib.mk will run and install them.
+
+TEST_CUSTOM_PROGS := $(OUTPUT)/sync_test
+all: $(TEST_CUSTOM_PROGS)
+
 OBJS = sync_test.o sync.o
 
 TESTS += sync_alloc.o
@@ -18,6 +22,16 @@ TESTS += sync_stress_parallelism.o
 TESTS += sync_stress_consumer.o
 TESTS += sync_stress_merge.o
 
-sync_test: $(OBJS) $(TESTS)
+OBJS := $(patsubst %,$(OUTPUT)/%,$(OBJS))
+TESTS := $(patsubst %,$(OUTPUT)/%,$(TESTS))
+
+$(TEST_CUSTOM_PROGS): $(TESTS) $(OBJS)
+	$(CC) -o $(TEST_CUSTOM_PROGS) $(OBJS) $(TESTS) $(CFLAGS) $(LDFLAGS)
+
+$(OBJS): $(OUTPUT)/%.o: %.c
+	$(CC) -c $^ -o $@
+
+$(TESTS): $(OUTPUT)/%.o: %.c
+	$(CC) -c $^ -o $@
 
-EXTRA_CLEAN := sync_test $(OBJS) $(TESTS)
+EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(OBJS) $(TESTS)
diff --git a/tools/testing/selftests/timers/set-timer-lat.c b/tools/testing/selftests/timers/set-timer-lat.c
index 9c92b7bd5641..50da45437daa 100644
--- a/tools/testing/selftests/timers/set-timer-lat.c
+++ b/tools/testing/selftests/timers/set-timer-lat.c
@@ -143,7 +143,8 @@ int setup_timer(int clock_id, int flags, int interval, timer_t *tm1)
 			printf("%-22s %s missing CAP_WAKE_ALARM?    : [UNSUPPORTED]\n",
 					clockstring(clock_id),
 					flags ? "ABSTIME":"RELTIME");
-			return 0;
+			/* Indicate timer isn't set, so caller doesn't wait */
+			return 1;
 		}
 		printf("%s - timer_create() failed\n", clockstring(clock_id));
 		return -1;
@@ -213,8 +214,9 @@ int do_timer(int clock_id, int flags)
 	int err;
 
 	err = setup_timer(clock_id, flags, interval, &tm1);
+	/* Unsupported case - return 0 to not fail the test */
 	if (err)
-		return err;
+		return err == 1 ? 0 : err;
 
 	while (alarmcount < 5)
 		sleep(1);
@@ -228,18 +230,17 @@ int do_timer_oneshot(int clock_id, int flags)
 	timer_t tm1;
 	const int interval = 0;
 	struct timeval timeout;
-	fd_set fds;
 	int err;
 
 	err = setup_timer(clock_id, flags, interval, &tm1);
+	/* Unsupported case - return 0 to not fail the test */
 	if (err)
-		return err;
+		return err == 1 ? 0 : err;
 
 	memset(&timeout, 0, sizeof(timeout));
 	timeout.tv_sec = 5;
-	FD_ZERO(&fds);
 	do {
-		err = select(FD_SETSIZE, &fds, NULL, NULL, &timeout);
+		err = select(0, NULL, NULL, NULL, &timeout);
 	} while (err == -1 && errno == EINTR);
 
 	timer_delete(tm1);
diff --git a/tools/testing/selftests/watchdog/Makefile b/tools/testing/selftests/watchdog/Makefile
index f863c664e3d1..ee068511fd0b 100644
--- a/tools/testing/selftests/watchdog/Makefile
+++ b/tools/testing/selftests/watchdog/Makefile
@@ -1,8 +1,3 @@
-TEST_PROGS := watchdog-test
-
-all: $(TEST_PROGS)
+TEST_GEN_PROGS := watchdog-test
 
 include ../lib.mk
-
-clean:
-	rm -fr $(TEST_PROGS)