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From: Dan Williams <dan.j.williams@intel.com>
Date: Wed, 19 Oct 2016 12:41:54 -0700
Message-ID: <CAPcyv4gbRE-ALJM6EHv6fM3Kq02HeZFMLF5T63J5qaJmHWvQCg@mail.gmail.com>
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Subject: Re: [Qemu-devel] [ndctl PATCH 0/8] dimm label space initialization
 support
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To: Eric Blake <eblake@redhat.com>
Cc: linux-nvdimm <linux-nvdimm@ml01.01.org>, Vishal L Verma <vishal.l.verma@intel.com>, qemu-devel@nongnu.org

On Wed, Oct 19, 2016 at 11:42 AM, Eric Blake <eblake@redhat.com> wrote:
> On 10/19/2016 11:47 AM, Dan Williams wrote:
>> The 4.9 kernel added support for sub-dividing PMEM.  With this kernel
>> patch [1] on top of that baseline, the PMEM-sub-division support can be
>> enabled for QEMU-KVM and any other platforms that advertise both un-aliased
>> PMEM regions and support for the label DSM commands [2].
>>
>> Given this increasing need to perform a label management operation
>> across a set of DIMMs this update also adds glob(3) support.  For
>> example you can now write commands like:
>>
>>     ndctl zero-labels nmem[2-4]
>
> This is slightly scary, as it depends on the user not having any file
> named nmem2, nmem3, or nmem4 in the current working directory.  Your
> example should probably encourage proper shell quoting, as in:
>
> ndctl zero-labels 'nmem[2-4]'

True.  Although, the glob is run against the list of present device
names in the system, so local files named nmem should change the
operation of the command.