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Subject: Re: [PATCH v3 6/7] libsas: add wait-complete support to sync
 discovery event
To: John Garry <john.garry@huawei.com>, <jejb@linux.vnet.ibm.com>,
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From: wangyijing <wangyijing@huawei.com>
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Date: Thu, 13 Jul 2017 10:19:44 +0800
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在 2017/7/12 21:51, John Garry 写道:
> On 10/07/2017 08:06, Yijing Wang wrote:
>>
>>  static void sas_chain_event(int event, unsigned long *pending,
>> @@ -592,9 +596,9 @@ int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
>>  {
>>      struct sas_discovery *disc;
>>
>> +    disc = &port->disc;
>>      if (!port)
>>          return 0;
>> -    disc = &port->disc;
>>
>>      BUG_ON(ev >= DISC_NUM_EVENTS);
>>
>> diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c
>> index 570b2cb..9d26c28 1
> 
> I was just looking through the code and I noticed this, above. Is there a specific reason to move the NULL check, or was it modified accidentally?
> 
> I mean, if port is NULL I don't think we would get as far as checking it as we would have already de-referenced it.

Oh, sorry, it's a accidental change, good catch, thanks!

> 
> 
> 
> .
>