Re: [PATCH] rtc: hid-sensor-time: Add missing spin_lock_init

Alexander Holler
2013-01-17T12:59:09Z

Am 17.01.2013 02:58, schrieb Thiago Farina:
> On Wed, Jan 16, 2013 at 11:49 PM, Axel Lin <axel.lin@ingics.com> wrote:
>> Signed-off-by: Axel Lin <axel.lin@ingics.com>
>> ---
>> drivers/rtc/rtc-hid-sensor-time.c | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/rtc/rtc-hid-sensor-time.c b/drivers/rtc/rtc-hid-sensor-time.c
>> index 0438c9e..31c5728 100644
>> --- a/drivers/rtc/rtc-hid-sensor-time.c
>> +++ b/drivers/rtc/rtc-hid-sensor-time.c
>> @@ -225,6 +225,7 @@ static int hid_time_probe(struct platform_device *pdev)
>>
>> platform_set_drvdata(pdev, time_state);
>>
>> + spin_lock_init(&time_state->lock_last_time);
> Can you explain in the commit message why it is missing?
>
> For people not familiar with this code that isn't obvious.
>

Every spinlock must be initialized once (to SPIN_LOCK_UNLOCKED or by
using spin_lock_init()). On most architectures SPIN_LOCK_UNLOCKED is
just zero, therefor the kzalloc of the time_state does it (which likely
is the case why I haven't spotted any error without the initialization),
but that doesn't isn't true for all architectures.

Regards,

Alexander