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Date:   Fri, 27 Aug 2021 18:45:43 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Jason Gunthorpe <jgg@ziepe.ca>
Cc:     Li Zhijian <lizhijian@cn.fujitsu.com>, linux-mm@kvack.org,
        linux-rdma@vger.kernel.org, akpm@linux-foundation.org,
        jglisse@redhat.com, yishaih@nvidia.com,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] mm/hmm: bypass devmap pte when all pfn requested flags
 are fulfilled
Message-ID: <YSkkx6Tci3n+qN54@infradead.org>
References: <20210827144500.2148-1-lizhijian@cn.fujitsu.com>
 <20210827162852.GL1200268@ziepe.ca>
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On Fri, Aug 27, 2021 at 01:28:52PM -0300, Jason Gunthorpe wrote:
> > +	/*
> > +	 * just bypass devmap pte such as DAX page when all pfn requested
> > +	 * flags(pfn_req_flags) are fulfilled.
> > +	 */
> > +	if (pte_devmap(pte))
> > +		goto out;
> 
> I liked your ealier version better where this was added to the
> pte_special test - logically this is about disambiguating the
> pte_special and the devmap case as they are different things.

Yes, I think that is much more logical.  Also please capitalize the
first word in multi-line comments.