From: Jeff Moyer <jmoyer@redhat.com>
Subject: Re: [PATCH v2 5/5] dax: handle media errors in dax_do_io
Date: Fri, 15 Apr 2016 14:06:23 -0400
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Cc: "Verma\, Vishal L" <vishal.l.verma@intel.com>,
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To: Dan Williams <dan.j.williams@intel.com>
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	(Dan Williams's message of "Fri, 15 Apr 2016 10:57:27 -0700")
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Dan Williams <dan.j.williams@intel.com> writes:

>>> There's a lot of special casing here, so you might consider adding
>>> comments.
>>
>> Correct - maybe we should reconsider wrapper-izing this? :)
>
> Another option is just to skip dax_do_io() and this special casing
> fallback entirely if errors are present.  I.e. only attempt dax_do_io
> when: IS_DAX() && gendisk->bb && bb->count == 0.

So, if there's an error anywhere on the device, penalize all I/O (not
just writes, and not just on sectors that are bad)?  I'm not sure that's
a great plan, either.

-Jeff

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