Date: Thu, 9 Jan 2014 12:14:36 -0800
From: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: KY Srinivasan <kys@microsoft.com>, "olaf@aepfle.de" <olaf@aepfle.de>,
        "jasowang@redhat.com" <jasowang@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "apw@canonical.com" <apw@canonical.com>,
        "devel@linuxdriverproject.org" <devel@linuxdriverproject.org>
Subject: Re: [PATCH 1/1] Drivers: hv: Implement the file copy service
Message-ID: <20140109201436.GA16425@kroah.com>
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On Thu, Jan 09, 2014 at 11:09:21PM +0300, Dan Carpenter wrote:
> We've had this discussion before where you urge me to trust the host...
> 
>  Problem: This code is racy.
> Solution: The host will only send one message at a time.
> 
> Now I have to audit the user space code on the host and I don't feel
> like doing that so you win.
> 
> I wish we had a better way to do IPC.  If kdbus were ready, that might
> have worked for this, and it's a better solution because both sender and
> reciever code will be written in a less trusting way.

kdbus is almost ready, it might make 3.15, depending on the result of
work that is happening at linux.conf.au and FOSDEM.

If it would be a better solution for this, that's even more reason to
get kdbus merged soon, no need to add something that doesn't really
work.

But, how will kdbus help with this?  It's a userspace <-> userspace
message transmission bus, would you want the kernel to be a receiver or
sender here?

thanks,

greg k-h
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