Re: [RFC PATCH] scsi: libsas: fix WARN on device removal

From: Dan Williams <dan.j.williams@intel.com>
To: John Garry <john.garry@huawei.com>
Cc: jejb@linux.vnet.ibm.com,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	wangyijing <wangyijing@huawei.com>,
	linux-scsi <linux-scsi@vger.kernel.org>,
	John Garry <john.garry2@mail.dcu.ie>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	linuxarm@huawei.com, lindar_liu@usish.com,
	Tejun Heo <tj@kernel.org>,
	Jinpu Wang <jinpu.wang@profitbricks.com>
Subject: Re: [RFC PATCH] scsi: libsas: fix WARN on device removal
Date: Thu, 17 Nov 2016 17:53:31 -0800	[thread overview]
Message-ID: <CAPcyv4g7_kDAZNZ2ikBRgFsX-hFpcXEV2xg9YS0Ha7PjSBkzVQ@mail.gmail.com> (raw)
In-Reply-To: <9bdd2ca5-aa72-6a18-b66d-8e791e4852c7@huawei.com>

On Thu, Nov 17, 2016 at 7:23 AM, John Garry <john.garry@huawei.com> wrote:
> On 11/11/2016 08:49, wangyijing wrote:
>>>>>
>>>>> I have not seen the flutter issue. I am just trying to solve the
>>>>> horrible WARN dump.
>>>>> However I do understand that there may be a issue related to how we
>>>>> queue the events; there was a recent attempt to fix this, but it came to
>>>>> nothing:
>>>>> https://www.spinics.net/lists/linux-scsi/msg99991.html
>>>>
>>>>
>>>> We found libsas hotplug several problems:
>>>> 1. sysfs warning calltrace(like the case you found);
>>>
>>>
>>> Maybe you can then review my patch.
>>
>>
>> I did it, I think your solution to fix the sysfs calltrace issue is ok,
>> and what I worried about is we still need to fix
>> the rest issues. So it's better if we could fix all issues one time.
>>
>
> @Maintainers, would you be willing to accept this patch as an interim fix
> for the dastardly WARN while we try to fix the flutter issue?

To me this adds a bug to quiet a benign, albeit noisy, warning.