From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cornelia Huck Subject: Re: [PATCH 4/6] KVM: s390: fix sigp set prefix status stored cases Date: Tue, 26 Jun 2012 17:39:39 +0200 Message-ID: <20120626173939.52617394@BR9GNB5Z> References: <1340719601-11867-1-git-send-email-cornelia.huck@de.ibm.com> <1340719601-11867-5-git-send-email-cornelia.huck@de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Avi Kivity , Marcelo Tosatti , Christian Borntraeger , Carsten Otte , Heiko Carstens , Martin Schwidefsky , KVM , linux-s390 To: Alexander Graf Return-path: Received: from e06smtp16.uk.ibm.com ([195.75.94.112]:50546 "EHLO e06smtp16.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758428Ab2FZPjp (ORCPT ); Tue, 26 Jun 2012 11:39:45 -0400 Received: from /spool/local by e06smtp16.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 26 Jun 2012 16:39:43 +0100 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On Tue, 26 Jun 2012 16:56:08 +0200 Alexander Graf wrote: > > On 26.06.2012, at 16:06, Cornelia Huck wrote: > > > From: Heiko Carstens > > > > If an invalid parameter is passed or the addressed cpu is in an > > incorrect state sigp set prefix will store a status. > > This status must only have bits set as defined by the architecture. > > The current kvm implementation missed to clear bits and also did > > not set the intended status bit ("and" instead of "or" operation). > > > > Signed-off-by: Heiko Carstens > > Signed-off-by: Cornelia Huck > > What was the net effect of this for a guest? Any problems rising from it? The guest might see some unexpected status bits if it did call sigp set prefix in an incorrect way. I'm not aware that anybody has actually seen that. Cornelia