From mboxrd@z Thu Jan  1 00:00:00 1970
From: Carsten Otte <cotte@de.ibm.com>
Subject: [patch 06/12] [PATCH] kvm-s390-ucontrol: disable in-kernel irq stack
Date: Fri, 09 Dec 2011 12:23:32 +0100
Message-ID: <20111209112751.665014501@de.ibm.com>
References: <20111209112326.454852716@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Martin Schwidefsky <schwidefsky@de.ibm.com>,
	Cornelia Huck <cornelia.huck@de.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>
To: Avi Kivity <avi@redhat.com>, Marcelo Tossati <mtosatti@redhat.com>
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Content-Disposition: inline; filename=kvm-disable-irq-stack.patch
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

This patch disables the in-kernel interrupt stack for KVM virtual
machines that are controlled by user. Userspace has to take care
of handling interrupts on its own.

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
---
Index: linux-2.5-cecsim/arch/s390/kvm/kvm-s390.c
===================================================================
--- linux-2.5-cecsim.orig/arch/s390/kvm/kvm-s390.c
+++ linux-2.5-cecsim/arch/s390/kvm/kvm-s390.c
@@ -511,7 +511,8 @@ static int __vcpu_run(struct kvm_vcpu *v
 	if (test_thread_flag(TIF_MCCK_PENDING))
 		s390_handle_mcck();
 
-	kvm_s390_deliver_pending_interrupts(vcpu);
+	if (!kvm_is_ucontrol(vcpu->kvm))
+		kvm_s390_deliver_pending_interrupts(vcpu);
 
 	vcpu->arch.sie_block->icptcode = 0;
 	local_irq_disable();