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Date: Wed, 10 Sep 2014 00:17:26 +0900
From: Tejun Heo <tj@kernel.org>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>,
        Shirish Pargaonkar <shirishpargaonkar@gmail.com>,
        Jens Axboe <axboe@kernel.dk>,
        SCSI development list <linux-scsi@vger.kernel.org>,
        Kernel development list <linux-kernel@vger.kernel.org>
Subject: Re: WARNING in block layer triggered in 3.17-rc3
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References: <20140909011945.GD11706@mtj.dyndns.org>
 <Pine.LNX.4.44L0.1409091026470.1677-100000@iolanthe.rowland.org>
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Hello, Alan.

On Tue, Sep 09, 2014 at 11:08:22AM -0400, Alan Stern wrote:
> Sorry, the meaning wasn't clear.  I meant that the existing code 
> doesn't work.  The patch seems to work okay (except that I can't use 
> queue_flag_test_and_set because the queue isn't locked at that point).  
> I'll submit the patch shortly.

Given it's fully synchronized, the following should work fine and
probably is less misleading than using atomic test_and_set.

	if (!blk_queue_init_done) {
		queue_flag_set_unlocked(QUEUE_FLAG_INIT_DONE, q);
		blk_queue_bypass_end(q);
	}

Thanks.

-- 
tejun