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From: Avi Kivity <avi@qumranet.com>
To: Arn <cse.syslab@gmail.com>
Cc: kvm@vger.kernel.org
Subject: Re: Sharing variables/memory between host and guest ?
Date: Sat, 19 Jul 2008 11:29:31 +0300	[thread overview]
Message-ID: <4881A5EB.4040000@qumranet.com> (raw)
In-Reply-To: <896ae46a0807141443p78df612csb5801d8ae7af17ca@mail.gmail.com>

Arn wrote:
>>> How can one share memory (a few variables not necessarily a page)
>>> between host/hypervisor and guest VM ?
>>>
>>>       
>> If you use the -mem-path qemu option, all guest memory will be in a file on
>> tmpfs.  You can mmap that file and access all guest memory.  Of course, this
>> is hitting the problem with a fairly bit hammer; more refined approaches are
>> possible.
>>     
>
> Could you outline the other approaches ?
>
>   

Have qemu expose the shared memory as a pci device, and write a guest 
driver to exploit it.  This is what the vga emulation does.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.


      reply	other threads:[~2008-07-19  8:29 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-07-12  0:16 Sharing variables/memory between host and guest ? Arn
2008-07-12 12:33 ` Dor Laor
2008-07-12 21:03   ` Arn
2008-07-12 21:15     ` Eric Van Hensbergen
2008-07-12 21:59       ` Arn
2008-07-12 22:06         ` Eric Van Hensbergen
2008-07-13 10:10 ` Avi Kivity
2008-07-14 21:43   ` Arn
2008-07-19  8:29     ` Avi Kivity [this message]

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