From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christian Borntraeger <borntraeger@de.ibm.com>
Subject: Re: [patch 3/3] kvm-s390: provide general purpose registers via kvm_run
Date: Thu, 22 Dec 2011 13:39:37 +0100
Message-ID: <4EF32509.80200@de.ibm.com>
References: <20111222115646.248800653@de.ibm.com> <20111222120054.367076904@de.ibm.com> <4EF323DB.5000203@redhat.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: Marcelo Tossati <mtosatti@redhat.com>,
	Carsten Otte <cotte@de.ibm.com>,
	Alexander Graf <agraf@suse.de>,
	Jens Freimann <jfrei@linux.vnet.ibm.com>,
	Cornelia Huck <cornelia.huck@de.ibm.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>,
	KVM <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
Return-path: <kvm-owner@vger.kernel.org>
Received: from e06smtp15.uk.ibm.com ([195.75.94.111]:43776 "EHLO
	e06smtp15.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1752642Ab1LVMjr (ORCPT <rfc822;kvm@vger.kernel.org>);
	Thu, 22 Dec 2011 07:39:47 -0500
Received: from /spool/local
	by e06smtp15.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted
	for <kvm@vger.kernel.org> from <borntraeger@de.ibm.com>;
	Thu, 22 Dec 2011 12:39:41 -0000
Received: from d06av11.portsmouth.uk.ibm.com (d06av11.portsmouth.uk.ibm.com [9.149.37.252])
	by d06nrmr1806.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id pBMCdd2O2826434
	for <kvm@vger.kernel.org>; Thu, 22 Dec 2011 12:39:39 GMT
Received: from d06av11.portsmouth.uk.ibm.com (loopback [127.0.0.1])
	by d06av11.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id pBMCdcbW027647
	for <kvm@vger.kernel.org>; Thu, 22 Dec 2011 05:39:39 -0700
In-Reply-To: <4EF323DB.5000203@redhat.com>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

On 22/12/11 13:34, Avi Kivity wrote:
>> The general purpose registers are often necessary to handle SIE exits.
>> Avoid additional ioctls by providing the guest registers in the r/w 
>> section of the kvm_run structure.
>>
> 
> This is only needed for S390_UCONTROL?

No for the standard path. It was more like a "we copy the regs around
anyway inside the kernel, so why not use kvm_run as a place to store 
the guest regs". So I will probably also have a look at floating point
regs and access registers.

> 
>>  
>>  struct sync_rw_regs {
>> +	__u64 gprs[16];	/* general purpose registers */
>>  };
>>  #endif
> 
> Don't you have to remove arch.guest_gprs too? (interesting approach btw).

Yes. Done