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Date:   Tue, 30 Jan 2018 23:15:01 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Alexey Skidanov <alexey.skidanov@intel.com>
Cc:     devel@driverdev.osuosl.org, labbott@redhat.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] staging: android: ion: Add implementation of
 dma_buf_vmap and dma_buf_vunmap
Message-ID: <20180130221501.GA6717@kroah.com>
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On Tue, Jan 30, 2018 at 10:39:13PM +0200, Alexey Skidanov wrote:
> dma_buf_vmap and dma_buf_vunmap allow drivers to access buffers, created by ion.

But why would anyone ever want to do that?  What is wrong with the
existing interfaces that drivers use to access buffers created by ion?

What code uses this new interface?

We need a bit more information please.

thanks,

greg k-h