From: "Takashi Sato" <t-sato@yk.jp.nec.com>
Subject: Re: [PATCH 3/3] Add timeout feature
Date: Mon, 29 Sep 2008 20:11:41 +0900
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To: "Ric Wheeler" <rwheeler@redhat.com>,
	"Christoph Hellwig" <hch@infradead.org>
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Hi Ric and Christoph,

Ric Wheeler wrote:
>>>> And as with all previous posting I still fundamentally disagree about
>>>> the need of this functionality.  We don't need a timeout for freezing.
>>>
>>> I agree with Christoph here, I think that the timeout is unneeded.
>>
>> I think that your concern is that the freezer cannot recognize the occurrence
>> of a timeout and it continues the backup process and the backup data is
>> corrupted finally.
>> If the freezer can recognize it by the unfreeze ioctl's errono, will your concern
>> be solved?
>> If so, I will implement it.
>>
>> Cheers, Takashi
>>
> I think that is certainly part a big part of my concern.
>
> Also note that the timeout seems to be quite low relative to say the standard timeout for a SCSI 
> device (30 seconds worst case).
>
> In general, I am quite supportive of the patch series and think that this is a great addition.

Thank you for your comments.
Christoph, do you have any comments about this solution?

If it's OK, I will change the freeze patch so that the unfreeze ioctl sets
ETIMEDOUT to errno when the timeout occurs.

Cheers, Takashi