[LTP] [PATCH] syscalls/move_pages12: Add new regression test
Guangwen Feng
fenggw-fnst@cn.fujitsu.com
Wed Jan 18 13:58:33 CET 2017
Fixed by:
commit e66f17ff71772b209eed39de35aaa99ba819c93d
Author: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Date: Wed Feb 11 15:25:22 2015 -0800
mm/hugetlb: take page table lock in follow_huge_pmd()
Signed-off-by: Guangwen Feng <fenggw-fnst@cn.fujitsu.com>
---
runtest/numa | 1 +
runtest/syscalls | 1 +
testcases/kernel/syscalls/.gitignore | 1 +
.../kernel/syscalls/move_pages/move_pages12.c | 171 +++++++++++++++++++++
4 files changed, 174 insertions(+)
create mode 100644 testcases/kernel/syscalls/move_pages/move_pages12.c
diff --git a/runtest/numa b/runtest/numa
index 87f64da..5dc6f48 100644
--- a/runtest/numa
+++ b/runtest/numa
@@ -10,3 +10,4 @@ move_pages08 move_pages.sh 08
move_pages09 move_pages.sh 09
move_pages10 move_pages.sh 10
move_pages11 cd $LTPROOT/testcases/bin && chown root move_pages11 && chmod 04755 move_pages11 && move_pages.sh 11
+move_pages12 move_pages.sh 12
diff --git a/runtest/syscalls b/runtest/syscalls
index 884ab80..9711cba 100644
--- a/runtest/syscalls
+++ b/runtest/syscalls
@@ -645,6 +645,7 @@ move_pages08 move_pages.sh 08
move_pages09 move_pages.sh 09
move_pages10 move_pages.sh 10
move_pages11 cd $LTPROOT/testcases/bin && chown root move_pages11 && chmod 04755 move_pages11 && move_pages.sh 11
+move_pages12 move_pages.sh 12
mprotect01 mprotect01
mprotect02 mprotect02
diff --git a/testcases/kernel/syscalls/.gitignore b/testcases/kernel/syscalls/.gitignore
index 3201fa9..21ed466 100644
--- a/testcases/kernel/syscalls/.gitignore
+++ b/testcases/kernel/syscalls/.gitignore
@@ -589,6 +589,7 @@
/move_pages/move_pages09
/move_pages/move_pages10
/move_pages/move_pages11
+/move_pages/move_pages12
/mprotect/mprotect01
/mprotect/mprotect02
/mprotect/mprotect03
diff --git a/testcases/kernel/syscalls/move_pages/move_pages12.c b/testcases/kernel/syscalls/move_pages/move_pages12.c
new file mode 100644
index 0000000..593d4ea
--- /dev/null
+++ b/testcases/kernel/syscalls/move_pages/move_pages12.c
@@ -0,0 +1,171 @@
+/*
+ * Copyright (c) 2016 Fujitsu Ltd.
+ * Author: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
+ * Ported: Guangwen Feng <fenggw-fnst@cn.fujitsu.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program, if not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * This is a regression test for the race condition between move_pages()
+ * and freeing hugepages, where move_pages() calls follow_page(FOLL_GET)
+ * for hugepages internally and tries to get its refcount without
+ * preventing concurrent freeing.
+ *
+ * This test can crash the buggy kernel, and the bug was fixed in:
+ *
+ * commit e66f17ff71772b209eed39de35aaa99ba819c93d
+ * Author: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
+ * Date: Wed Feb 11 15:25:22 2015 -0800
+ *
+ * mm/hugetlb: take page table lock in follow_huge_pmd()
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "tst_test.h"
+#include "tst_safe_stdio.h"
+#include "move_pages_support.h"
+
+#define LOOPS 10000
+#define PATH_MEMINFO "/proc/meminfo"
+#define PATH_NR_HUGEPAGES "/proc/sys/vm/nr_hugepages"
+#define PATH_HUGEPAGES "/sys/kernel/mm/hugepages/"
+#define TEST_PAGES 2
+#define TEST_NODES 2
+#define TEST_ADDR 0x700000000000UL
+
+static int pgsz, hpsz;
+static long orig_hugepages;
+
+static int read_hugepagesize(void)
+{
+ FILE *fp;
+ char line[BUFSIZ], buf[BUFSIZ];
+ int val;
+
+ fp = SAFE_FOPEN(PATH_MEMINFO, "r");
+ while (fgets(line, BUFSIZ, fp) != NULL) {
+ if (sscanf(line, "%64s %d", buf, &val) == 2) {
+ if (strcmp(buf, "Hugepagesize:") == 0) {
+ SAFE_FCLOSE(fp);
+ return 1024 * val;
+ }
+ }
+ }
+
+ SAFE_FCLOSE(fp);
+ tst_brk(TBROK, "can't find \"%s\" in %s",
+ "Hugepagesize:", PATH_MEMINFO);
+}
+
+static void do_child(void)
+{
+ char *p;
+
+ while (1) {
+ p = SAFE_MMAP((void *)TEST_ADDR, TEST_PAGES * hpsz,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0);
+ if (p != (void *)TEST_ADDR)
+ tst_brk(TBROK, "Failed to mmap at desired addr");
+
+ memset(p, 0, TEST_PAGES * hpsz);
+
+ SAFE_MUNMAP(p, TEST_PAGES * hpsz);
+ }
+}
+
+static void verify_move_pages(void)
+{
+#if HAVE_NUMA_MOVE_PAGES
+ unsigned int node1, node2;
+ int i, j, ret;
+ int test_pages = TEST_PAGES * hpsz / pgsz;
+ int *nodes, *status;
+ void **pages;
+ pid_t cpid;
+
+ ret = get_allowed_nodes(NH_MEMS, TEST_NODES, &node1, &node2);
+ if (ret < 0)
+ tst_brk(TBROK | TERRNO, "get_allowed_nodes: %d", ret);
+
+ pages = SAFE_MALLOC(sizeof(char *) * test_pages + 1);
+ nodes = SAFE_MALLOC(sizeof(char *) * test_pages + 1);
+ status = SAFE_MALLOC(sizeof(char *) * test_pages + 1);
+
+ for (i = 0; i < test_pages; i++)
+ pages[i] = (void *)TEST_ADDR + i * pgsz;
+
+ cpid = SAFE_FORK();
+ if (cpid == 0)
+ do_child();
+
+ for (i = 0; i < LOOPS; i++) {
+ for (j = 0; j < test_pages; j++) {
+ if (i % 2 == 0)
+ nodes[j] = node1;
+ else
+ nodes[j] = node2;
+ status[j] = 0;
+ }
+
+ TEST(numa_move_pages(cpid, test_pages, pages, nodes, status,
+ MPOL_MF_MOVE_ALL));
+ if (TEST_RETURN) {
+ tst_res(TFAIL | TTERRNO, "move_pages failed");
+ break;
+ }
+ }
+
+ SAFE_KILL(cpid, SIGKILL);
+ SAFE_WAITPID(cpid, NULL, 0);
+
+ if (i == LOOPS)
+ tst_res(TPASS, "Bug not reproduced");
+#else
+ tst_res(TCONF, "move_pages support not found.");
+#endif
+}
+
+static void setup(void)
+{
+ check_config(TEST_NODES);
+
+ if (access(PATH_HUGEPAGES, F_OK))
+ tst_brk(TCONF, "Huge page not supported.");
+
+ pgsz = (int)get_page_size();
+ hpsz = read_hugepagesize();
+
+ SAFE_FILE_SCANF(PATH_NR_HUGEPAGES, "%ld", &orig_hugepages);
+ SAFE_FILE_PRINTF(PATH_NR_HUGEPAGES, "%d", 40);
+}
+
+static void cleanup(void)
+{
+ SAFE_FILE_PRINTF(PATH_NR_HUGEPAGES, "%ld", orig_hugepages);
+}
+
+static struct tst_test test = {
+ .tid = "move_pages12",
+ .min_kver = "2.6.32",
+ .needs_root = 1,
+ .forks_child = 1,
+ .setup = setup,
+ .cleanup = cleanup,
+ .test_all = verify_move_pages,
+};
--
1.8.4.2
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