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Subject: Re: [PATCH v2 1/2] libsas: Don't process sas events in static works
To: Johannes Thumshirn <jthumshirn@suse.de>, <jejb@linux.vnet.ibm.com>,
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From: wangyijing <wangyijing@huawei.com>
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Date: Wed, 14 Jun 2017 17:04:28 +0800
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>>  static void notify_ha_event(struct sas_ha_struct *sas_ha, enum ha_event event)
>>  {
>> +	struct sas_ha_event *ev;
>> +
>>  	BUG_ON(event >= HA_NUM_EVENTS);
>>  
>> -	sas_queue_event(event, &sas_ha->pending,
>> -			&sas_ha->ha_events[event].work, sas_ha);
>> +	ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
>> +	if (!ev)
>> +		return;
> GFP_ATOMIC allocations can fail and then no events will be queued *and* we
> don't report the error back to the caller.
> 

Yes, it's really a problem, but I don't find a better solution, do you have some suggestion ?

> 
> 
>> index 64e9cdd..c227a8b 100644
>> --- a/drivers/scsi/libsas/sas_init.c
>> +++ b/drivers/scsi/libsas/sas_init.c
>> @@ -111,10 +111,6 @@ void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
>>  
>>  void sas_hae_reset(struct work_struct *work)
>>  {
>> -	struct sas_ha_event *ev = to_sas_ha_event(work);
>> -	struct sas_ha_struct *ha = ev->ha;
>> -
>> -	clear_bit(HAE_RESET, &ha->pending);
>>  }
> 
> I don't really get why you need a stubbed out sas_hae_reset(). Can't we
> just kill it if it doesn't have anything left to do?

I have no idea about this function history, I agree clean it out.

> 
>