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Date:   Thu, 28 Mar 2019 08:55:06 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     Sasha Levin <sashal@kernel.org>
Cc:     linux-nvme@lists.infradead.org, Christoph Hellwig <hch@lst.de>,
        Yi Zhang <yi.zhang@redhat.com>,
        Sagi Grimberg <sagi@grimberg.me>,
        Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>,
        stable@vger.kernel.org
Subject: Re: [PATCH stable only] nvmet: set loop queue's segment boundary
 mask as PAGE_SIZE - 1
Message-ID: <20190328005505.GB19708@ming.t460p>
References: <20190327090230.12671-1-ming.lei@redhat.com>
 <20190327161658.GL25262@sasha-vm>
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On Wed, Mar 27, 2019 at 12:16:58PM -0400, Sasha Levin wrote:
> On Wed, Mar 27, 2019 at 05:02:30PM +0800, Ming Lei wrote:
> > NVMe target only accepts single-page sg list, either file or block
> > device backed target code follows this assumption.
> > 
> > However, loop target is one exception, given the sg list is from
> > the host queue directly.
> > 
> > This patch sets loop queue's segment boundary mask as PAGE_SIZE - 1
> > for following NVMe target assumption.
> > 
> > Reported-by: Yi Zhang <yi.zhang@redhat.com>
> > Fixes: 3a85a5de29ea ("nvme-loop: add a NVMe loopback host driver")
> > Cc: Yi Zhang <yi.zhang@redhat.com>
> > Cc: Sagi Grimberg <sagi@grimberg.me>
> > Cc: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
> > Cc: <stable@vger.kernel.org>
> > Signed-off-by: Ming Lei <ming.lei@redhat.com>
> 
> Could you provide some background as to why this is -stable only in the
> commit message?

Multi-page bvec has been merged to linus tree already, so the following
patch simply can fix the current issue without needing to limit the segment
size for nvme-loop:

http://lists.infradead.org/pipermail/linux-nvme/2019-March/023105.html

Thanks,
Ming