Subject: [PATCH v13 11/24] selftests/vm: fix alloc_random_pkey() to make it really random

From: Ram Pai <[email-masked]>
Date: Wed, 13 Jun 2018 17:45:02 -0700

alloc_random_pkey() was allocating the same pkey every time.
Not all pkeys were geting tested. fixed it.

cc: Dave Hansen <[email-masked]>
cc: Florian Weimer <[email-masked]>
Signed-off-by: Ram Pai <[email-masked]>
---
 tools/testing/selftests/vm/protection_keys.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)

diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 42a91c7..c5f9776 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -24,6 +24,7 @@
 #define _GNU_SOURCE
 #include <errno.h>
 #include <linux/futex.h>
+#include <time.h>
 #include <sys/time.h>
 #include <sys/syscall.h>
 #include <string.h>
@@ -576,13 +577,15 @@ int alloc_random_pkey(void)
 	int alloced_pkeys[NR_PKEYS];
 	int nr_alloced = 0;
 	int random_index;
+
 	memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
+	srand((unsigned int)time(NULL));
 
 	/* allocate every possible key and make a note of which ones we got */
 	max_nr_pkey_allocs = NR_PKEYS;
-	max_nr_pkey_allocs = 1;
 	for (i = 0; i < max_nr_pkey_allocs; i++) {
 		int new_pkey = alloc_pkey();
+
 		if (new_pkey < 0)
 			break;
 		alloced_pkeys[nr_alloced++] = new_pkey;
@@ -598,6 +601,7 @@ int alloc_random_pkey(void)
 	/* go through the allocated ones that we did not want and free them */
 	for (i = 0; i < nr_alloced; i++) {
 		int free_ret;
+
 		if (!alloced_pkeys[i])
 			continue;
 		free_ret = sys_pkey_free(alloced_pkeys[i]);
-- 
1.7.1