2017-08-08 23:28:58

by Daniel Mentz

Subject: [PATCH] kmod: test_kmod: Correctly lock reg_dev_mutex

It appears that, in the preamble of register_test_dev_kmod(),
mutex_lock() has been confused with mutex_unlock().

Previously, register_test_dev_kmod() never called mutex_lock() but
instead, it called mutex_unlock() twice.

Signed-off-by: Daniel Mentz <[email protected]>
Cc: Luis R. Rodriguez <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Andrew Morton <[email protected]>
---
lib/test_kmod.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/test_kmod.c b/lib/test_kmod.c
index 6c1d678bcf8b..f458130a5e65 100644
--- a/lib/test_kmod.c
+++ b/lib/test_kmod.c
@@ -1146,7 +1146,7 @@ static struct kmod_test_device *register_test_dev_kmod(void)
struct kmod_test_device *test_dev = NULL;
int ret;

- mutex_unlock(&reg_dev_mutex);
+ mutex_lock(&reg_dev_mutex);

/* int should suffice for number of devices, test for wrap */
if (unlikely(num_test_devs + 1) < 0) {
--
2.14.0.434.g98096fd7a8-goog

2017-08-09 19:29:43

by Luis Chamberlain

Subject: Re: [PATCH] kmod: test_kmod: Correctly lock reg_dev_mutex

On Tue, Aug 08, 2017 at 04:27:33PM -0700, Daniel Mentz wrote:
> It appears that, in the preamble of register_test_dev_kmod(),
> mutex_lock() has been confused with mutex_unlock().
>
> Previously, register_test_dev_kmod() never called mutex_lock() but
> instead, it called mutex_unlock() twice.
>
> Signed-off-by: Daniel Mentz <[email protected]>
> Cc: Luis R. Rodriguez <[email protected]>
> Cc: Greg Kroah-Hartman <[email protected]>
> Cc: Andrew Morton <[email protected]>
> ---

Thanks Daniel but someone beat you to the fix, I've sent this to Andrew
and he's integrated into his -mm tree. See:

http://lkml.kernel.org/r/[email protected]

This series had other fixes:

https://marc.info/?l=linux-kernel&m=150170850624962&w=2

I'll CC you on other kmod / test_kmod changes.

Luis

2017-08-09 21:56:55

by Daniel Mentz

Subject: Re: [PATCH] kmod: test_kmod: Correctly lock reg_dev_mutex

OK. While we're here: I think there's a spelling error in usage() in
tools/testing/selftests/kmod/kmod.sh

echo " -c Run test ID once"
echo " -s Run test ID x test-count number of times"

I believe that "-c" and "-s" are swapped. "c" probably stands for
count and "s" for single.

2017-08-09 22:35:08

by Luis Chamberlain

Subject: Re: [PATCH] kmod: test_kmod: Correctly lock reg_dev_mutex

On Wed, Aug 09, 2017 at 02:56:52PM -0700, Daniel Mentz wrote:
> OK. While we're here: I think there's a spelling error in usage() in
> tools/testing/selftests/kmod/kmod.sh
>
> echo " -c Run test ID once"
> echo " -s Run test ID x test-count number of times"
>
> I believe that "-c" and "-s" are swapped. "c" probably stands for
> count and "s" for single.

Indeed, will send a fix. Thanks!

Luis