From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [PATCH RFC 2/4] xen: grant_table: implement
	grant_table_soft_reset()
Date: Thu, 4 Jun 2015 16:22:14 +0100
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On 04/06/15 15:11, Tim Deegan wrote:
> 
> There has been talk before of an operation along the lines of "revoke
> this grant entry and wait for all users to release it" but that would
> only help with backends that are guaranteed to release grants in a
> reasonable time.

Are you talking about my idea? This would be immediate because the grant
mapper would provide a local page to atomically switch the foreign
mapping to when the grant is revoked.

But, this isn't something that would be generally applicable to all grants.

David