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Date:   Mon, 19 Apr 2021 08:36:30 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Subject: Re: [Resend RFC PATCH V2 07/12] HV/Vmbus: Initialize VMbus ring
 buffer for Isolation VM
Message-ID: <20210419063630.GA18882@lst.de>
References: <20210414144945.3460554-1-ltykernel@gmail.com> <20210414144945.3460554-8-ltykernel@gmail.com> <YHig78Xra5tEQhMD@dhcp-10-154-102-149.vpn.oracle.com>
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On Thu, Apr 15, 2021 at 04:24:15PM -0400, Konrad Rzeszutek Wilk wrote:
> So you are exposing these two:
>  EXPORT_SYMBOL_GPL(get_vm_area);
>  EXPORT_SYMBOL_GPL(ioremap_page_range);
> 
> But if you used vmap wouldn't you get the same thing for free?

Yes, this needs to go into some vmap version, preferably reusing the
existing code in kernel/dma/remap.c.

Exporting get_vm_area is a complete dealbreaker and not going to happen.
We worked hard on not exposing it to modules.