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Subject: Re: Re: BUG in kernel: Wrong Handling of USB
 =?UTF-8?Q?HDD=E2=80=99s?= in scsiglue(slave_configure) and
 scsi/sd(sd_read_cache_type)
From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Douglas Gilbert <dgilbert@interlog.com>,
        Amit Sahrawat <amit.sahrawat83@gmail.com>, linux-usb@vger.kernel.org,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, Christoph Hellwig <hch@infradead.org>
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Date: Mon, 03 Oct 2011 14:32:35 -0500
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On Mon, 2011-10-03 at 14:10 -0400, Alan Stern wrote:
> > No. You need to also take into account the RBC
> > device parameters mode page if present. See above.
> 
> All right, suppose neither page is present.  Does it then make sense to 
> assume by default that write caching is enabled?

You're the USB expert ... if we do that, we'll start sending
SYNCHRONIZE_CACHE commands down to a whole slew of devices we didn't
before ... is that going to cause problems with any USB SATLs?

James