[LTP] [PATCH v2] syscalls/move_pages12: Add new regression test

[Guangwen Feng <fenggw-fnst@cn.fujitsu.com>]

Hi!

Sorry, I find there is something wrong with the V2,
please ignore it, I will send a V3.

Best Regards,
Guangwen Feng

On 02/08/2017 05:19 PM, Guangwen Feng wrote:
> 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      | 165 +++++++++++++++++++++
>  4 files changed, 168 insertions(+)
>  create mode 100644 testcases/kernel/syscalls/move_pages/move_pages12.c
> 
> diff --git a/runtest/numa b/runtest/numa
> index 87f64da..dcf4948 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_pages12
> diff --git a/runtest/syscalls b/runtest/syscalls
> index dc03c4c..48f6492 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_pages12
>  
>  mprotect01 mprotect01
>  mprotect02 mprotect02
> diff --git a/testcases/kernel/syscalls/.gitignore b/testcases/kernel/syscalls/.gitignore
> index 91dccef..bebaa89 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..f0c5a9f
> --- /dev/null
> +++ b/testcases/kernel/syscalls/move_pages/move_pages12.c
> @@ -0,0 +1,165 @@
> +/*
> + * 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 <unistd.h>
> +#include <string.h>
> +#include <sys/types.h>
> +
> +#include "tst_test.h"
> +#include "move_pages_support.h"
> +
> +#if HAVE_NUMA_MOVE_PAGES
> +
> +#define LOOPS	1000
> +#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
> +
> +static int pgsz, hpsz;
> +static long orig_hugepages;
> +static unsigned int node1, node2;
> +static void *addr;
> +
> +static void do_child(void)
> +{
> +	int test_pages = TEST_PAGES * hpsz / pgsz;
> +	int i, j;
> +	int *nodes, *status;
> +	void **pages;
> +	pid_t ppid = getppid();
> +
> +	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] = addr + i * pgsz;
> +
> +	for (i = 0; ; 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(ppid, test_pages,
> +			pages, nodes, status, MPOL_MF_MOVE_ALL));
> +		if (TEST_RETURN) {
> +			tst_res(TFAIL | TTERRNO, "move_pages failed");
> +			break;
> +		}
> +	}
> +
> +	exit(0);
> +}
> +
> +static void do_test(void)
> +{
> +	int i;
> +	pid_t cpid = -1;
> +	int status;
> +
> +	for (i = 0; i < LOOPS; i++) {
> +		addr = SAFE_MMAP(NULL, TEST_PAGES * hpsz,
> +			PROT_READ | PROT_WRITE,
> +			MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0);
> +
> +		memset(addr, 0, TEST_PAGES * hpsz);
> +
> +		SAFE_MUNMAP(addr, TEST_PAGES * hpsz);
> +
> +		if (i == 0) {
> +			cpid = SAFE_FORK();
> +			if (cpid == 0)
> +				do_child();
> +		}
> +	}
> +
> +	if (i == LOOPS) {
> +		SAFE_KILL(cpid, SIGKILL);
> +		SAFE_WAITPID(cpid, &status, 0);
> +		if (!WIFEXITED(status))
> +			tst_res(TPASS, "Bug not reproduced");
> +	}
> +}
> +
> +static void setup(void)
> +{
> +	int memfree, ret;
> +
> +	check_config(TEST_NODES);
> +
> +	if (access(PATH_HUGEPAGES, F_OK))
> +		tst_brk(TCONF, "Huge page not supported");
> +
> +	pgsz = (int)get_page_size();
> +	SAFE_FILE_LINES_SCANF(PATH_MEMINFO, "Hugepagesize: %d", &hpsz);
> +	hpsz *= 1024;
> +
> +	SAFE_FILE_LINES_SCANF(PATH_MEMINFO, "MemFree: %d", &memfree);
> +	memfree *= 1024;
> +	if (4 * hpsz > memfree)
> +		tst_brk(TBROK, "RAM not enough");
> +
> +	SAFE_FILE_SCANF(PATH_NR_HUGEPAGES, "%ld", &orig_hugepages);
> +	SAFE_FILE_PRINTF(PATH_NR_HUGEPAGES, "%ld", orig_hugepages + 4);
> +
> +	ret = get_allowed_nodes(NH_MEMS, TEST_NODES, &node1, &node2);
> +	if (ret < 0)
> +		tst_brk(TBROK | TERRNO, "get_allowed_nodes: %d", ret);
> +}
> +
> +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 = do_test,
> +};
> +
> +#else
> +	tst_res(TCONF, "move_pages support not found");
> +#endif
>