From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [usb-storage] Re: Fwd: 2TB USB hard drive for backing up
Date: Tue, 22 Jan 2013 11:05:26 -0600
Message-ID: <50FEC6D6.3030708@zytor.com>
References: <Pine.LNX.4.44L0.1301221039350.1510-100000@iolanthe.rowland.org>
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To: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oneukum@suse.de>, James Bottomley <James.Bottomley@hansenpartnership.com>, Ellwood Blues <elwood.blue@gmail.com>, linux-efi@vger.kernel.org, linux-scsi <linux-scsi@vger.kernel.org>, USB Storage List <usb-storage@lists.one-eyed-alien.net>
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On 01/22/2013 09:43 AM, Alan Stern wrote:
> On Tue, 22 Jan 2013, Oliver Neukum wrote:
> 
>> On Tuesday 22 January 2013 11:05:35 James Bottomley wrote:
>>>> May  3 18:19:06 relampago3 kernel: [ 3948.472796] sd 7:0:0:0: [sdf]
>>>> 1565565872 512-byte logical blocks: (801 GB/746 GiB)
>>>
>>> This looks like a wrap around of your actual size.  This appears to
>>> indicate the device isn't replying correctly to READ CAPACITY.  The
>>> conventional return from READ CAPACITY should be -1 which would trigger
>>> us to retry with READ CAPACITY(16).
>>
>> What can we do? The answer the device is giving is quite ordinary.
>> Do we need another quirk and an associated flag?
> 
> The JMicron bridges are well known to be fairly buggy.  Another quirk 
> may indeed be the only solution.  Oliver, would you like to write a 
> patch for it?
> 

Would it make more sense to try READ CAPACITY(16) first?  Or does that
have other bad effects?

	-hpa