From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Fang <fangwei1@huawei.com>
Subject: Re: [PATCH] scsi: fix race between simultaneous decrements of
 ->host_failed
Date: Mon, 30 May 2016 15:43:43 +0800
Message-ID: <574BEF2F.9070707@huawei.com>
References: <1464407471-3712-1-git-send-email-fangwei1@huawei.com>
 <20160529065452.GA21677@infradead.org>
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To: Christoph Hellwig <hch@infradead.org>
Cc: tj@kernel.org, jejb@linux.vnet.ibm.com, martin.petersen@oracle.com, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org
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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

> 
> .
>