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From:   Dan Williams <dan.j.williams@intel.com>
Date:   Tue, 4 Sep 2018 08:57:47 -0700
Message-ID: <CAPcyv4iVYjbs_ds9tL4rceH5cSck=D-AkkejFh+rHXdY25nGfw@mail.gmail.com>
Subject: Re: [PATCH v2] libnvdimm, region_devs: stop NDD_ALIASING bit test if
 one test pass
To:     Ocean He <oceanhehy@gmail.com>
Cc:     Ross Zwisler <ross.zwisler@linux.intel.com>,
        Vishal L Verma <vishal.l.verma@intel.com>,
        Dave Jiang <dave.jiang@intel.com>,
        linux-nvdimm <linux-nvdimm@lists.01.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Ocean He <hehy1@lenovo.com>
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On Tue, Sep 4, 2018 at 3:47 AM, Ocean He <oceanhehy@gmail.com> wrote:
> From: Ocean He <hehy1@lenovo.com>
>
> There is no need to finish entire loop to execute NDD_ALIASING bit test
> against every nvdimm->flags.

Of course there is. I see nothing stopping someone mixing an NVDIMM
that supports labels with one that doesn't. If anything I think we
need fixes to make sure this operates correctly to force disable
BLK-mode capactiy when the PMEM capacity is interleaved with a
label-less NVDIMM.