From mboxrd@z Thu Jan  1 00:00:00 1970
From: Carsten Otte <cotte@de.ibm.com>
Subject: Re: [patch 04/12] [PATCH] kvm-s390-ucontrol: export SIE control block
 to user
Date: Fri, 09 Dec 2011 12:54:46 +0100
Message-ID: <4EE1F706.6040506@de.ibm.com>
References: <20111209112326.454852716@de.ibm.com> <20111209112751.447335351@de.ibm.com> <614FD809-BDDC-488A-BBB9-3BD9E1A955F9@suse.de>
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Cc: Avi Kivity <avi@redhat.com>, Marcelo Tossati <mtosatti@redhat.com>,
	borntrae@linux.vnet.ibm.com, heicars2@linux.vnet.ibm.com,
	mschwid2@linux.vnet.ibm.com, huckc@linux.vnet.ibm.com,
	KVM <kvm@vger.kernel.org>,
	Joachim von Buttlar <joachim_von_buttlar@de.ibm.com>,
	Jens Freimann <jfrei@de.ibm.com>,
	Constantin Werner <constantin.werner@de.ibm.com>,
	Xiantao Zhang <xiantao.zhang@intel.com>
To: Alexander Graf <agraf@suse.de>
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On 09.12.2011 12:37, Alexander Graf wrote:
>> +#define KVM_S390_SIE_PAGE_OFFSET 1
>
> Can we please make these a global number space? I don't want to have any user space code "accidently" call this mmap while it's trying to find out if it can map the PIO page. We already have a global number space for CAPs.
I consider a vma with holes in it pretty ugly, and we've got the 
mechanism for userspace to correctly find out where to find what.
I do prefer a contiguous vma and the existing capabilities/queries.
Avi?