[1/2] zdtm: Make file_locks04 test based on /proc/{pid}/fdinfo/{fd}

Submitted by Kirill Tkhai on June 28, 2016, 5:49 p.m.

Details

Message ID 146713610824.18194.17792090529402446259.stgit@pro
State Rejected
Series "Series without cover letter"
Headers show

Commit Message

Kirill Tkhai June 28, 2016, 5:49 p.m.
/proc/locks is racy with adding/removing locks,
so we may lose test lock on a check.

Use fdinfo list of locks instead.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
---
 test/zdtm/static/file_locks04.c |   32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

Patch hide | download patch | download mbox

diff --git a/test/zdtm/static/file_locks04.c b/test/zdtm/static/file_locks04.c
index 995dd09..dfb7c53 100644
--- a/test/zdtm/static/file_locks04.c
+++ b/test/zdtm/static/file_locks04.c
@@ -6,6 +6,7 @@ 
 #include <unistd.h>
 #include <sys/file.h>
 #include <string.h>
+#include <limits.h>
 #include <sys/wait.h>
 
 #include "zdtmtst.h"
@@ -16,27 +17,27 @@  const char *test_author	= "Pavel Emelyanov <xemul@parallels.com>";
 char *filename;
 TEST_OPTION(filename, string, "file name", 1);
 
-static int check_file_locks(int alt_pid, int fd)
+static int check_file_locks(pid_t child_pid, int fd, int child_fd)
 {
+	char		path[PATH_MAX];
 	FILE		*fp_locks = NULL;
 	char		buf[100], fl_flag[16], fl_type[16], fl_option[16];
-	pid_t		pid = getpid();
 	int		found = 0, num, fl_owner;
 
-	fp_locks = fopen("/proc/locks", "r");
-	if (!fp_locks)
+	sprintf(path, "/proc/%d/fdinfo/%d", child_pid, child_fd);
+	fp_locks = fopen(path, "r");
+	if (!fp_locks) {
+		pr_err("Can't open %s\n", path);
 		return -1;
-
-	test_msg("C: %d/%d\n", pid, alt_pid);
+	}
 
 	while (fgets(buf, sizeof(buf), fp_locks)) {
-		test_msg("c: %s", buf);
-
-		if (strstr(buf, "->"))
+		if (strncmp(buf, "lock:\t", 6) != 0)
 			continue;
+		test_msg("c: %s", buf);
 
 		num = sscanf(buf,
-			"%*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
+			"%*s %*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
 			fl_flag, fl_type, fl_option, &fl_owner);
 
 		if (num < 4) {
@@ -44,8 +45,10 @@  static int check_file_locks(int alt_pid, int fd)
 			break;
 		}
 
-		if (fl_owner != pid && fl_owner != alt_pid)
+		if (fl_owner != child_pid && fl_owner != getpid()) {
+			pr_err("Wrong owner\n");
 			continue;
+		}
 
 		if (!strcmp(fl_flag, "FLOCK") &&
 				!strcmp(fl_type, "ADVISORY") &&
@@ -67,11 +70,11 @@  static int check_file_locks(int alt_pid, int fd)
 
 int main(int argc, char **argv)
 {
-	int fd, pid;
+	int fd, child_fd, pid, ret;
 
 	test_init(argc, argv);
 
-	fd = open(filename, O_CREAT | O_RDWR, 0600);
+	fd = child_fd = open(filename, O_CREAT | O_RDWR, 0600);
 	if (fd < 0) {
 		pr_perror("No file");
 		return -1;
@@ -105,11 +108,12 @@  int main(int argc, char **argv)
 	test_daemon();
 	test_waitsig();
 
-	if (check_file_locks(pid, fd))
+	if (check_file_locks(pid, fd, child_fd) > 0)
 		pass();
 	else
 		fail("Flock file locks check failed");
 
+out_kill:
 	kill(pid, SIGTERM);
 	waitpid(pid, NULL, 0);
 	close(fd);

Comments

Andrey Vagin June 28, 2016, 6:02 p.m.
On Tue, Jun 28, 2016 at 08:49:04PM +0300, Kirill Tkhai wrote:
> /proc/locks is racy with adding/removing locks,
> so we may lose test lock on a check.
> 
> Use fdinfo list of locks instead.

fdinfo contains locks starting with the 4.1 kernel, how this test will
work on older kernels?

What is about other file_locks* tests?

> 
> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
> ---
>  test/zdtm/static/file_locks04.c |   32 ++++++++++++++++++--------------
>  1 file changed, 18 insertions(+), 14 deletions(-)
> 
> diff --git a/test/zdtm/static/file_locks04.c b/test/zdtm/static/file_locks04.c
> index 995dd09..dfb7c53 100644
> --- a/test/zdtm/static/file_locks04.c
> +++ b/test/zdtm/static/file_locks04.c
> @@ -6,6 +6,7 @@
>  #include <unistd.h>
>  #include <sys/file.h>
>  #include <string.h>
> +#include <limits.h>
>  #include <sys/wait.h>
>  
>  #include "zdtmtst.h"
> @@ -16,27 +17,27 @@ const char *test_author	= "Pavel Emelyanov <xemul@parallels.com>";
>  char *filename;
>  TEST_OPTION(filename, string, "file name", 1);
>  
> -static int check_file_locks(int alt_pid, int fd)
> +static int check_file_locks(pid_t child_pid, int fd, int child_fd)
>  {
> +	char		path[PATH_MAX];
>  	FILE		*fp_locks = NULL;
>  	char		buf[100], fl_flag[16], fl_type[16], fl_option[16];
> -	pid_t		pid = getpid();
>  	int		found = 0, num, fl_owner;
>  
> -	fp_locks = fopen("/proc/locks", "r");
> -	if (!fp_locks)
> +	sprintf(path, "/proc/%d/fdinfo/%d", child_pid, child_fd);
> +	fp_locks = fopen(path, "r");
> +	if (!fp_locks) {
> +		pr_err("Can't open %s\n", path);
>  		return -1;
> -
> -	test_msg("C: %d/%d\n", pid, alt_pid);
> +	}
>  
>  	while (fgets(buf, sizeof(buf), fp_locks)) {
> -		test_msg("c: %s", buf);
> -
> -		if (strstr(buf, "->"))
> +		if (strncmp(buf, "lock:\t", 6) != 0)
>  			continue;
> +		test_msg("c: %s", buf);
>  
>  		num = sscanf(buf,
> -			"%*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
> +			"%*s %*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
>  			fl_flag, fl_type, fl_option, &fl_owner);
>  
>  		if (num < 4) {
> @@ -44,8 +45,10 @@ static int check_file_locks(int alt_pid, int fd)
>  			break;
>  		}
>  
> -		if (fl_owner != pid && fl_owner != alt_pid)
> +		if (fl_owner != child_pid && fl_owner != getpid()) {
> +			pr_err("Wrong owner\n");
>  			continue;
> +		}
>  
>  		if (!strcmp(fl_flag, "FLOCK") &&
>  				!strcmp(fl_type, "ADVISORY") &&
> @@ -67,11 +70,11 @@ static int check_file_locks(int alt_pid, int fd)
>  
>  int main(int argc, char **argv)
>  {
> -	int fd, pid;
> +	int fd, child_fd, pid, ret;
>  
>  	test_init(argc, argv);
>  
> -	fd = open(filename, O_CREAT | O_RDWR, 0600);
> +	fd = child_fd = open(filename, O_CREAT | O_RDWR, 0600);
>  	if (fd < 0) {
>  		pr_perror("No file");
>  		return -1;
> @@ -105,11 +108,12 @@ int main(int argc, char **argv)
>  	test_daemon();
>  	test_waitsig();
>  
> -	if (check_file_locks(pid, fd))
> +	if (check_file_locks(pid, fd, child_fd) > 0)
>  		pass();
>  	else
>  		fail("Flock file locks check failed");
>  
> +out_kill:
>  	kill(pid, SIGTERM);
>  	waitpid(pid, NULL, 0);
>  	close(fd);
>
Kirill Tkhai June 28, 2016, 6:05 p.m.
On 28.06.2016 21:02, Andrew Vagin wrote:
> On Tue, Jun 28, 2016 at 08:49:04PM +0300, Kirill Tkhai wrote:
>> /proc/locks is racy with adding/removing locks,
>> so we may lose test lock on a check.
>>
>> Use fdinfo list of locks instead.
> 
> fdinfo contains locks starting with the 4.1 kernel, how this test will
> work on older kernels?
> 
> What is about other file_locks* tests?

See the second patch
 
>>
>> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
>> ---
>>  test/zdtm/static/file_locks04.c |   32 ++++++++++++++++++--------------
>>  1 file changed, 18 insertions(+), 14 deletions(-)
>>
>> diff --git a/test/zdtm/static/file_locks04.c b/test/zdtm/static/file_locks04.c
>> index 995dd09..dfb7c53 100644
>> --- a/test/zdtm/static/file_locks04.c
>> +++ b/test/zdtm/static/file_locks04.c
>> @@ -6,6 +6,7 @@
>>  #include <unistd.h>
>>  #include <sys/file.h>
>>  #include <string.h>
>> +#include <limits.h>
>>  #include <sys/wait.h>
>>  
>>  #include "zdtmtst.h"
>> @@ -16,27 +17,27 @@ const char *test_author	= "Pavel Emelyanov <xemul@parallels.com>";
>>  char *filename;
>>  TEST_OPTION(filename, string, "file name", 1);
>>  
>> -static int check_file_locks(int alt_pid, int fd)
>> +static int check_file_locks(pid_t child_pid, int fd, int child_fd)
>>  {
>> +	char		path[PATH_MAX];
>>  	FILE		*fp_locks = NULL;
>>  	char		buf[100], fl_flag[16], fl_type[16], fl_option[16];
>> -	pid_t		pid = getpid();
>>  	int		found = 0, num, fl_owner;
>>  
>> -	fp_locks = fopen("/proc/locks", "r");
>> -	if (!fp_locks)
>> +	sprintf(path, "/proc/%d/fdinfo/%d", child_pid, child_fd);
>> +	fp_locks = fopen(path, "r");
>> +	if (!fp_locks) {
>> +		pr_err("Can't open %s\n", path);
>>  		return -1;
>> -
>> -	test_msg("C: %d/%d\n", pid, alt_pid);
>> +	}
>>  
>>  	while (fgets(buf, sizeof(buf), fp_locks)) {
>> -		test_msg("c: %s", buf);
>> -
>> -		if (strstr(buf, "->"))
>> +		if (strncmp(buf, "lock:\t", 6) != 0)
>>  			continue;
>> +		test_msg("c: %s", buf);
>>  
>>  		num = sscanf(buf,
>> -			"%*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
>> +			"%*s %*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
>>  			fl_flag, fl_type, fl_option, &fl_owner);
>>  
>>  		if (num < 4) {
>> @@ -44,8 +45,10 @@ static int check_file_locks(int alt_pid, int fd)
>>  			break;
>>  		}
>>  
>> -		if (fl_owner != pid && fl_owner != alt_pid)
>> +		if (fl_owner != child_pid && fl_owner != getpid()) {
>> +			pr_err("Wrong owner\n");
>>  			continue;
>> +		}
>>  
>>  		if (!strcmp(fl_flag, "FLOCK") &&
>>  				!strcmp(fl_type, "ADVISORY") &&
>> @@ -67,11 +70,11 @@ static int check_file_locks(int alt_pid, int fd)
>>  
>>  int main(int argc, char **argv)
>>  {
>> -	int fd, pid;
>> +	int fd, child_fd, pid, ret;
>>  
>>  	test_init(argc, argv);
>>  
>> -	fd = open(filename, O_CREAT | O_RDWR, 0600);
>> +	fd = child_fd = open(filename, O_CREAT | O_RDWR, 0600);
>>  	if (fd < 0) {
>>  		pr_perror("No file");
>>  		return -1;
>> @@ -105,11 +108,12 @@ int main(int argc, char **argv)
>>  	test_daemon();
>>  	test_waitsig();
>>  
>> -	if (check_file_locks(pid, fd))
>> +	if (check_file_locks(pid, fd, child_fd) > 0)
>>  		pass();
>>  	else
>>  		fail("Flock file locks check failed");
>>  
>> +out_kill:
>>  	kill(pid, SIGTERM);
>>  	waitpid(pid, NULL, 0);
>>  	close(fd);
>>
Kirill Tkhai June 28, 2016, 6:06 p.m.
On 28.06.2016 21:02, Andrew Vagin wrote:
> On Tue, Jun 28, 2016 at 08:49:04PM +0300, Kirill Tkhai wrote:
>> /proc/locks is racy with adding/removing locks,
>> so we may lose test lock on a check.
>>
>> Use fdinfo list of locks instead.
> 
> fdinfo contains locks starting with the 4.1 kernel, how this test will
> work on older kernels?
> 
> What is about other file_locks* tests?

They should be fixed as well if they need.
 
>>
>> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
>> ---
>>  test/zdtm/static/file_locks04.c |   32 ++++++++++++++++++--------------
>>  1 file changed, 18 insertions(+), 14 deletions(-)
>>
>> diff --git a/test/zdtm/static/file_locks04.c b/test/zdtm/static/file_locks04.c
>> index 995dd09..dfb7c53 100644
>> --- a/test/zdtm/static/file_locks04.c
>> +++ b/test/zdtm/static/file_locks04.c
>> @@ -6,6 +6,7 @@
>>  #include <unistd.h>
>>  #include <sys/file.h>
>>  #include <string.h>
>> +#include <limits.h>
>>  #include <sys/wait.h>
>>  
>>  #include "zdtmtst.h"
>> @@ -16,27 +17,27 @@ const char *test_author	= "Pavel Emelyanov <xemul@parallels.com>";
>>  char *filename;
>>  TEST_OPTION(filename, string, "file name", 1);
>>  
>> -static int check_file_locks(int alt_pid, int fd)
>> +static int check_file_locks(pid_t child_pid, int fd, int child_fd)
>>  {
>> +	char		path[PATH_MAX];
>>  	FILE		*fp_locks = NULL;
>>  	char		buf[100], fl_flag[16], fl_type[16], fl_option[16];
>> -	pid_t		pid = getpid();
>>  	int		found = 0, num, fl_owner;
>>  
>> -	fp_locks = fopen("/proc/locks", "r");
>> -	if (!fp_locks)
>> +	sprintf(path, "/proc/%d/fdinfo/%d", child_pid, child_fd);
>> +	fp_locks = fopen(path, "r");
>> +	if (!fp_locks) {
>> +		pr_err("Can't open %s\n", path);
>>  		return -1;
>> -
>> -	test_msg("C: %d/%d\n", pid, alt_pid);
>> +	}
>>  
>>  	while (fgets(buf, sizeof(buf), fp_locks)) {
>> -		test_msg("c: %s", buf);
>> -
>> -		if (strstr(buf, "->"))
>> +		if (strncmp(buf, "lock:\t", 6) != 0)
>>  			continue;
>> +		test_msg("c: %s", buf);
>>  
>>  		num = sscanf(buf,
>> -			"%*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
>> +			"%*s %*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
>>  			fl_flag, fl_type, fl_option, &fl_owner);
>>  
>>  		if (num < 4) {
>> @@ -44,8 +45,10 @@ static int check_file_locks(int alt_pid, int fd)
>>  			break;
>>  		}
>>  
>> -		if (fl_owner != pid && fl_owner != alt_pid)
>> +		if (fl_owner != child_pid && fl_owner != getpid()) {
>> +			pr_err("Wrong owner\n");
>>  			continue;
>> +		}
>>  
>>  		if (!strcmp(fl_flag, "FLOCK") &&
>>  				!strcmp(fl_type, "ADVISORY") &&
>> @@ -67,11 +70,11 @@ static int check_file_locks(int alt_pid, int fd)
>>  
>>  int main(int argc, char **argv)
>>  {
>> -	int fd, pid;
>> +	int fd, child_fd, pid, ret;
>>  
>>  	test_init(argc, argv);
>>  
>> -	fd = open(filename, O_CREAT | O_RDWR, 0600);
>> +	fd = child_fd = open(filename, O_CREAT | O_RDWR, 0600);
>>  	if (fd < 0) {
>>  		pr_perror("No file");
>>  		return -1;
>> @@ -105,11 +108,12 @@ int main(int argc, char **argv)
>>  	test_daemon();
>>  	test_waitsig();
>>  
>> -	if (check_file_locks(pid, fd))
>> +	if (check_file_locks(pid, fd, child_fd) > 0)
>>  		pass();
>>  	else
>>  		fail("Flock file locks check failed");
>>  
>> +out_kill:
>>  	kill(pid, SIGTERM);
>>  	waitpid(pid, NULL, 0);
>>  	close(fd);
>>
Andrey Vagin June 28, 2016, 6:17 p.m.
On Tue, Jun 28, 2016 at 09:06:30PM +0300, Kirill Tkhai wrote:
> 
> 
> On 28.06.2016 21:02, Andrew Vagin wrote:
> > On Tue, Jun 28, 2016 at 08:49:04PM +0300, Kirill Tkhai wrote:
> >> /proc/locks is racy with adding/removing locks,
> >> so we may lose test lock on a check.
> >>
> >> Use fdinfo list of locks instead.
> > 
> > fdinfo contains locks starting with the 4.1 kernel, how this test will
> > work on older kernels?
> > 
> > What is about other file_locks* tests?
> 
> They should be fixed as well if they need.

Could you fix them too and remove the excl flag from desc files?

>  
> >>
> >> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
> >> ---
> >>  test/zdtm/static/file_locks04.c |   32 ++++++++++++++++++--------------
> >>  1 file changed, 18 insertions(+), 14 deletions(-)
> >>
> >> diff --git a/test/zdtm/static/file_locks04.c b/test/zdtm/static/file_locks04.c
> >> index 995dd09..dfb7c53 100644
> >> --- a/test/zdtm/static/file_locks04.c
> >> +++ b/test/zdtm/static/file_locks04.c
> >> @@ -6,6 +6,7 @@
> >>  #include <unistd.h>
> >>  #include <sys/file.h>
> >>  #include <string.h>
> >> +#include <limits.h>
> >>  #include <sys/wait.h>
> >>  
> >>  #include "zdtmtst.h"
> >> @@ -16,27 +17,27 @@ const char *test_author	= "Pavel Emelyanov <xemul@parallels.com>";
> >>  char *filename;
> >>  TEST_OPTION(filename, string, "file name", 1);
> >>  
> >> -static int check_file_locks(int alt_pid, int fd)
> >> +static int check_file_locks(pid_t child_pid, int fd, int child_fd)
> >>  {
> >> +	char		path[PATH_MAX];
> >>  	FILE		*fp_locks = NULL;
> >>  	char		buf[100], fl_flag[16], fl_type[16], fl_option[16];
> >> -	pid_t		pid = getpid();
> >>  	int		found = 0, num, fl_owner;
> >>  
> >> -	fp_locks = fopen("/proc/locks", "r");
> >> -	if (!fp_locks)
> >> +	sprintf(path, "/proc/%d/fdinfo/%d", child_pid, child_fd);
> >> +	fp_locks = fopen(path, "r");
> >> +	if (!fp_locks) {
> >> +		pr_err("Can't open %s\n", path);
> >>  		return -1;
> >> -
> >> -	test_msg("C: %d/%d\n", pid, alt_pid);
> >> +	}
> >>  
> >>  	while (fgets(buf, sizeof(buf), fp_locks)) {
> >> -		test_msg("c: %s", buf);
> >> -
> >> -		if (strstr(buf, "->"))
> >> +		if (strncmp(buf, "lock:\t", 6) != 0)
> >>  			continue;
> >> +		test_msg("c: %s", buf);
> >>  
> >>  		num = sscanf(buf,
> >> -			"%*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
> >> +			"%*s %*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
> >>  			fl_flag, fl_type, fl_option, &fl_owner);
> >>  
> >>  		if (num < 4) {
> >> @@ -44,8 +45,10 @@ static int check_file_locks(int alt_pid, int fd)
> >>  			break;
> >>  		}
> >>  
> >> -		if (fl_owner != pid && fl_owner != alt_pid)
> >> +		if (fl_owner != child_pid && fl_owner != getpid()) {
> >> +			pr_err("Wrong owner\n");
> >>  			continue;
> >> +		}
> >>  
> >>  		if (!strcmp(fl_flag, "FLOCK") &&
> >>  				!strcmp(fl_type, "ADVISORY") &&
> >> @@ -67,11 +70,11 @@ static int check_file_locks(int alt_pid, int fd)
> >>  
> >>  int main(int argc, char **argv)
> >>  {
> >> -	int fd, pid;
> >> +	int fd, child_fd, pid, ret;
> >>  
> >>  	test_init(argc, argv);
> >>  
> >> -	fd = open(filename, O_CREAT | O_RDWR, 0600);
> >> +	fd = child_fd = open(filename, O_CREAT | O_RDWR, 0600);
> >>  	if (fd < 0) {
> >>  		pr_perror("No file");
> >>  		return -1;
> >> @@ -105,11 +108,12 @@ int main(int argc, char **argv)
> >>  	test_daemon();
> >>  	test_waitsig();
> >>  
> >> -	if (check_file_locks(pid, fd))
> >> +	if (check_file_locks(pid, fd, child_fd) > 0)
> >>  		pass();
> >>  	else
> >>  		fail("Flock file locks check failed");
> >>  
> >> +out_kill:
> >>  	kill(pid, SIGTERM);
> >>  	waitpid(pid, NULL, 0);
> >>  	close(fd);
> >>
Kirill Tkhai June 28, 2016, 6:20 p.m.
On 28.06.2016 21:17, Andrew Vagin wrote:
> On Tue, Jun 28, 2016 at 09:06:30PM +0300, Kirill Tkhai wrote:
>>
>>
>> On 28.06.2016 21:02, Andrew Vagin wrote:
>>> On Tue, Jun 28, 2016 at 08:49:04PM +0300, Kirill Tkhai wrote:
>>>> /proc/locks is racy with adding/removing locks,
>>>> so we may lose test lock on a check.
>>>>
>>>> Use fdinfo list of locks instead.
>>>
>>> fdinfo contains locks starting with the 4.1 kernel, how this test will
>>> work on older kernels?
>>>
>>> What is about other file_locks* tests?
>>
>> They should be fixed as well if they need.
> 
> Could you fix them too and remove the excl flag from desc files?

Maybe later, not this week.
 
>>  
>>>>
>>>> Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
>>>> ---
>>>>  test/zdtm/static/file_locks04.c |   32 ++++++++++++++++++--------------
>>>>  1 file changed, 18 insertions(+), 14 deletions(-)
>>>>
>>>> diff --git a/test/zdtm/static/file_locks04.c b/test/zdtm/static/file_locks04.c
>>>> index 995dd09..dfb7c53 100644
>>>> --- a/test/zdtm/static/file_locks04.c
>>>> +++ b/test/zdtm/static/file_locks04.c
>>>> @@ -6,6 +6,7 @@
>>>>  #include <unistd.h>
>>>>  #include <sys/file.h>
>>>>  #include <string.h>
>>>> +#include <limits.h>
>>>>  #include <sys/wait.h>
>>>>  
>>>>  #include "zdtmtst.h"
>>>> @@ -16,27 +17,27 @@ const char *test_author	= "Pavel Emelyanov <xemul@parallels.com>";
>>>>  char *filename;
>>>>  TEST_OPTION(filename, string, "file name", 1);
>>>>  
>>>> -static int check_file_locks(int alt_pid, int fd)
>>>> +static int check_file_locks(pid_t child_pid, int fd, int child_fd)
>>>>  {
>>>> +	char		path[PATH_MAX];
>>>>  	FILE		*fp_locks = NULL;
>>>>  	char		buf[100], fl_flag[16], fl_type[16], fl_option[16];
>>>> -	pid_t		pid = getpid();
>>>>  	int		found = 0, num, fl_owner;
>>>>  
>>>> -	fp_locks = fopen("/proc/locks", "r");
>>>> -	if (!fp_locks)
>>>> +	sprintf(path, "/proc/%d/fdinfo/%d", child_pid, child_fd);
>>>> +	fp_locks = fopen(path, "r");
>>>> +	if (!fp_locks) {
>>>> +		pr_err("Can't open %s\n", path);
>>>>  		return -1;
>>>> -
>>>> -	test_msg("C: %d/%d\n", pid, alt_pid);
>>>> +	}
>>>>  
>>>>  	while (fgets(buf, sizeof(buf), fp_locks)) {
>>>> -		test_msg("c: %s", buf);
>>>> -
>>>> -		if (strstr(buf, "->"))
>>>> +		if (strncmp(buf, "lock:\t", 6) != 0)
>>>>  			continue;
>>>> +		test_msg("c: %s", buf);
>>>>  
>>>>  		num = sscanf(buf,
>>>> -			"%*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
>>>> +			"%*s %*d:%s %s %s %d %*02x:%*02x:%*d %*d %*s",
>>>>  			fl_flag, fl_type, fl_option, &fl_owner);
>>>>  
>>>>  		if (num < 4) {
>>>> @@ -44,8 +45,10 @@ static int check_file_locks(int alt_pid, int fd)
>>>>  			break;
>>>>  		}
>>>>  
>>>> -		if (fl_owner != pid && fl_owner != alt_pid)
>>>> +		if (fl_owner != child_pid && fl_owner != getpid()) {
>>>> +			pr_err("Wrong owner\n");
>>>>  			continue;
>>>> +		}
>>>>  
>>>>  		if (!strcmp(fl_flag, "FLOCK") &&
>>>>  				!strcmp(fl_type, "ADVISORY") &&
>>>> @@ -67,11 +70,11 @@ static int check_file_locks(int alt_pid, int fd)
>>>>  
>>>>  int main(int argc, char **argv)
>>>>  {
>>>> -	int fd, pid;
>>>> +	int fd, child_fd, pid, ret;
>>>>  
>>>>  	test_init(argc, argv);
>>>>  
>>>> -	fd = open(filename, O_CREAT | O_RDWR, 0600);
>>>> +	fd = child_fd = open(filename, O_CREAT | O_RDWR, 0600);
>>>>  	if (fd < 0) {
>>>>  		pr_perror("No file");
>>>>  		return -1;
>>>> @@ -105,11 +108,12 @@ int main(int argc, char **argv)
>>>>  	test_daemon();
>>>>  	test_waitsig();
>>>>  
>>>> -	if (check_file_locks(pid, fd))
>>>> +	if (check_file_locks(pid, fd, child_fd) > 0)
>>>>  		pass();
>>>>  	else
>>>>  		fail("Flock file locks check failed");
>>>>  
>>>> +out_kill:
>>>>  	kill(pid, SIGTERM);
>>>>  	waitpid(pid, NULL, 0);
>>>>  	close(fd);
>>>>