From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oliver Neukum <oneukum@suse.com>
Subject: Re: [PATCH] USB: storage: add "no SYNCHRONIZE CACHE" quirk
Date: Tue, 15 Dec 2015 12:34:31 +0100
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References: <Pine.LNX.4.44L0.1512031320580.1324-100000@iolanthe.rowland.org>
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To: Alan Stern <stern@rowland.harvard.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>, Greg KH <greg@kroah.com>, Jun Itou <itou_jun@infoseek.jp>, Markus Rathgeb <maggu2810@gmail.com>, Matt <vickm78@hotmail.com>, SCSI development list <linux-scsi@vger.kernel.org>, USB Storage list <usb-storage@lists.one-eyed-alien.net>, USB list <linux-usb@vger.kernel.org>, Jens Axboe <axboe@kernel.dk>, Dan Williams <dcbw@redhat.com>, brad <bradhaack@fastmail.us>

On Thu, 2015-12-03 at 13:36 -0500, Alan Stern wrote:
> This is an old problem, but it was never resolved and it still affects
> people (Bugzilla #89511).  In short, there are USB-(S)ATA bridges that
> claim to be write-back but don't support the SYNCHRONIZE CACHE
> command.  
> This causes errors when filesystems try to flush data out to the disk.

OK, maybe this is a stupid idea, but could we test the command as we
enumerate the slave and store the result?

	Regards
		Oliver