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Date:   Wed, 8 Jan 2020 16:04:47 +0100
From:   "hch@lst.de" <hch@lst.de>
To:     "Singh, Balbir" <sblbir@amazon.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Chaitanya.Kulkarni@wdc.com" <Chaitanya.Kulkarni@wdc.com>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
        "hch@lst.de" <hch@lst.de>,
        "jejb@linux.ibm.com" <jejb@linux.ibm.com>,
        "mst@redhat.com" <mst@redhat.com>,
        "axboe@kernel.dk" <axboe@kernel.dk>,
        "Sangaraju, Someswarudu" <ssomesh@amazon.com>
Subject: Re: [resend v1 4/5] drivers/nvme/host/core.c: Convert to use
 disk_set_capacity
Message-ID: <20200108150447.GC10975@lst.de>
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On Mon, Jan 06, 2020 at 12:46:26AM +0000, Singh, Balbir wrote:
> On Sat, 2020-01-04 at 22:27 +0000, Chaitanya Kulkarni wrote:
> > Quick question here if user executes nvme ns-rescan /dev/nvme1
> > will following code result in triggering uevent(s) for
> > the namespace(s( for which there is no change in the size ?
> > 
> > If so is that an expected behavior ?
> > 
> 
> My old code had a check to see if old_capacity != new_capacity as well.
> I can redo those bits if needed.
> 
> The expected behaviour is not clear, but the functionality is not broken, user
> space should be able to deal with a resize event where the previous capacity
> == new capacity IMHO.

I think it makes sense to not bother with a notification unless there
is an actual change.