Changes since V1:
1. Enhance patch header.
2. Use BITS_PER_LONG and set_node() to simplify the logic.

In kernel, if user specified more nodes, e.g, 512 nodes, than the
supported, e.g, 4 nodes, kernel will check if the non supported
part, e.g, 508 nodes, is all zeroed in node bitmap. Currently, we
are overrunning "nmask", whose length is shorter than MAXNODES,
and where the unsupported bits should be cleared to pass the check.

Signed-off-by: Lans Zhang <lans.zhang2008@gmail.com>
---
  testcases/kernel/mem/cpuset/cpuset01.c |   11 +++++++----
  testcases/kernel/mem/include/mem.h     |    7 +++++++
  testcases/kernel/mem/ksm/ksm02.c       |    6 +++---
  testcases/kernel/mem/ksm/ksm04.c       |    6 +++---
  testcases/kernel/mem/lib/mem.c         |    9 +++++----
  5 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/testcases/kernel/mem/cpuset/cpuset01.c b/testcases/kernel/mem/cpuset/cpuset01.c
index 1069335..99fbb9c 100644
--- a/testcases/kernel/mem/cpuset/cpuset01.c
+++ b/testcases/kernel/mem/cpuset/cpuset01.c
@@ -93,7 +93,7 @@ static void testcpuset(void)
  {
  	int lc;
  	int child, i, status;
-	unsigned long nmask = 0;
+	unsigned long nmask[MAXNODES / BITS_PER_LONG] = { 0 };
  	char mems[BUFSIZ], buf[BUFSIZ];

  	read_cpuset_files(CPATH, "cpus", buf);
@@ -107,9 +107,12 @@ static void testcpuset(void)
  	case -1:
  		tst_brkm(TBROK | TERRNO, cleanup, "fork");
  	case 0:
-		for (i = 0; i < nnodes; i++)
-			nmask += 1 << nodes[i];
-		if (set_mempolicy(MPOL_BIND, &nmask, MAXNODES) == -1)
+		for (i = 0; i < nnodes; i++) {
+			if (nodes[i] >= MAXNODES)
+				continue;
+			set_node(nmask, nodes[i]);
+		}
+		if (set_mempolicy(MPOL_BIND, nmask, MAXNODES) == -1)
  			tst_brkm(TBROK | TERRNO, cleanup, "set_mempolicy");
  		exit(mem_hog_cpuset(ncpus > 1 ? ncpus : 1));
  	}
diff --git a/testcases/kernel/mem/include/mem.h b/testcases/kernel/mem/include/mem.h
index fdf558e..f54aa17 100644
--- a/testcases/kernel/mem/include/mem.h
+++ b/testcases/kernel/mem/include/mem.h
@@ -14,6 +14,13 @@
  #define PATH_SYS_SYSTEM		"/sys/devices/system"
  #define PATH_SYSVM		"/proc/sys/vm/"
  #define PATH_MEMINFO		"/proc/meminfo"
+#define BITS_PER_LONG           (8 * sizeof(long))
+
+static inline void set_node(unsigned long *array, unsigned int node,
+                            unsigned int v)
+{
+	array[node / BITS_PER_LONG] |= 1UL << (node % BITS_PER_LONG);
+}

  /* OOM */

diff --git a/testcases/kernel/mem/ksm/ksm02.c b/testcases/kernel/mem/ksm/ksm02.c
index 412b52e..6c96c74 100644
--- a/testcases/kernel/mem/ksm/ksm02.c
+++ b/testcases/kernel/mem/ksm/ksm02.c
@@ -87,7 +87,7 @@ int main(int argc, char *argv[])
  	int lc;
  	char *msg;
  	int size = 128, num = 3, unit = 1;
-	unsigned long nmask = 0;
+	unsigned long nmask[MAXNODES / BITS_PER_LONG] = { 0 };
  	unsigned int node;

  	msg = parse_opts(argc, argv, ksm_options, ksm_usage);
@@ -95,7 +95,7 @@ int main(int argc, char *argv[])
  		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);

  	node = get_a_numa_node(tst_exit);
-	nmask = 1 << node;
+	set_node(nmask, node);

  	setup();

@@ -103,7 +103,7 @@ int main(int argc, char *argv[])
  		tst_count = 0;
  		check_ksm_options(&size, &num, &unit);

-		if (set_mempolicy(MPOL_BIND, &nmask, MAXNODES) == -1) {
+		if (set_mempolicy(MPOL_BIND, nmask, MAXNODES) == -1) {
  			if (errno != ENOSYS)
  				tst_brkm(TBROK | TERRNO, cleanup,
  					 "set_mempolicy");
diff --git a/testcases/kernel/mem/ksm/ksm04.c b/testcases/kernel/mem/ksm/ksm04.c
index e164b29..ed5e0b3 100644
--- a/testcases/kernel/mem/ksm/ksm04.c
+++ b/testcases/kernel/mem/ksm/ksm04.c
@@ -87,7 +87,7 @@ int main(int argc, char *argv[])
  	int lc;
  	char *msg;
  	int size = 128, num = 3, unit = 1;
-	unsigned long nmask = 0;
+	unsigned long nmask[MAXNODES / BITS_PER_LONG] = { 0 };
  	unsigned int node;

  	msg = parse_opts(argc, argv, ksm_options, ksm_usage);
@@ -95,7 +95,7 @@ int main(int argc, char *argv[])
  		tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);

  	node = get_a_numa_node(tst_exit);
-	nmask = 1 << node;
+	set_node(nmask, node);

  	setup();

@@ -105,7 +105,7 @@ int main(int argc, char *argv[])

  		write_memcg();

-		if (set_mempolicy(MPOL_BIND, &nmask, MAXNODES) == -1) {
+		if (set_mempolicy(MPOL_BIND, nmask, MAXNODES) == -1) {
  			if (errno != ENOSYS)
  				tst_brkm(TBROK | TERRNO, cleanup,
  					 "set_mempolicy");
diff --git a/testcases/kernel/mem/lib/mem.c b/testcases/kernel/mem/lib/mem.c
index c9525e5..69ea046 100644
--- a/testcases/kernel/mem/lib/mem.c
+++ b/testcases/kernel/mem/lib/mem.c
@@ -95,7 +95,7 @@ void testoom(int mempolicy, int lite)
  {
  #if HAVE_NUMA_H && HAVE_LINUX_MEMPOLICY_H && HAVE_NUMAIF_H \
  	&& HAVE_MPOL_CONSTANTS
-	unsigned long nmask = 0;
+	unsigned long nmask[MAXNODES / BITS_PER_LONG] = { 0 };
  	unsigned int num_nodes, *nodes;
  	int ret;

@@ -112,7 +112,7 @@ void testoom(int mempolicy, int lite)
  		switch(mempolicy) {
  		case MPOL_BIND:
  			/* bind the second node */
-			nmask = 1 << nodes[1];
+			set_node(nmask, nodes[1]);
  			break;
  		case MPOL_INTERLEAVE:
  		case MPOL_PREFERRED:
@@ -123,13 +123,14 @@ void testoom(int mempolicy, int lite)
  				return;
  			} else {
  				/* Using the 2nd,3rd node */
-				nmask = (1 << nodes[1]) | (1 << nodes[2]);
+				set_node(nmask, nodes[1]);
+				set_node(nmask, nodes[2]);
  			}
  			break;
  		default:
  			tst_brkm(TBROK|TERRNO, cleanup, "Bad mempolicy mode");
  		}
-		if (set_mempolicy(mempolicy, &nmask, MAXNODES) == -1)
+		if (set_mempolicy(mempolicy, nmask, MAXNODES) == -1)
  			tst_brkm(TBROK|TERRNO, cleanup, "set_mempolicy");
  	}
  #endif
-- 
1.7.8.110.g4cb5d