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Date:   Fri, 18 Mar 2022 09:40:11 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     John Hubbard <jhubbard@nvidia.com>
Cc:     Mika =?utf-8?B?UGVudHRpbMOk?= <mpenttil@redhat.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        apopple@nvidia.com, rcampbell@nvidia.com, vbabka@suse.cz
Subject: Re: [PATCH v2] mm/hmm/test: simplify hmm test code: use miscdevice
 instead of char dev
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On Thu, Mar 17, 2022 at 07:58:25PM -0700, John Hubbard wrote:
> In other words, given that the usage here is correct, is there some
> reason that miscdevice is still a poor design fit? Is cdev_device_add()
> a better choice here, for design reasons?

cdev's have become so easy to use I don't see the few loc reduction to
add miscdev that valuable. IMHO

> Also, is there any change that could or should be made to miscdevice,
> that you have in mind?

No, it is just a legacy interface that was simplifies drivers that
create a single char dev in static data that is widely misused.

IOW I wouldn't add new miscdevs.

Jason