Re: [PATCH] scsi: fix race between simultaneous decrements of ->host_failed

[Wei Fang <fangwei1@huawei.com>]

Hi, Christoph,

On 2016/5/29 14:54, Christoph Hellwig wrote:
> On Sat, May 28, 2016 at 11:51:11AM +0800, Wei Fang wrote:
>> async_sas_ata_eh(), which will call scsi_eh_finish_cmd() in some case,
>> would be performed simultaneously in sas_ata_strategy_handler(). In this
>> case, ->host_failed may be decreased simultaneously in
>> scsi_eh_finish_cmd() on different CPUs, and become abnormal.
>>
>> It will lead to permanently inequal between ->host_failed and
>>  ->host_busy. Then SCSI error handler thread won't become running,
>> SCSI errors after that won't be handled forever.
>>
>> Use atomic type for ->host_failed to fix this race.
> 
> Looks fine,
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> 
> But please also update Documentation/scsi/scsi_eh.txt for this
> change.

Thanks for reviewing the patch.
I looked around the file, and didn't find the part should be updated.
Would you point me out?

Thanks,
Wei

> 
> .
>