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Date:   Wed, 27 Jan 2021 08:10:59 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc:     Nicholas Piggin <npiggin@gmail.com>, linux-mm@kvack.org,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org,
        Robin Murphy <robin.murphy@arm.com>,
        Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 2/5] kernel/dma: remove unnecessary unmap_kernel_range
Message-ID: <20210127071059.GA21133@lst.de>
References: <20210126045404.2492588-1-npiggin@gmail.com> <20210126045404.2492588-3-npiggin@gmail.com> <YBCS7toITTwP04aK@Konrads-MacBook-Pro.local>
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On Tue, Jan 26, 2021 at 05:08:46PM -0500, Konrad Rzeszutek Wilk wrote:
> On Tue, Jan 26, 2021 at 02:54:01PM +1000, Nicholas Piggin wrote:
> > vunmap will remove ptes.
> 
> Should there be some ASSERT after the vunmap to make sure that is the
> case? 

Not really.  removing the PTEs is the whole point of vunmap.  Everything
else is just house keeping.