From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753258AbbIGMdS (ORCPT ); Mon, 7 Sep 2015 08:33:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45542 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751255AbbIGMdO (ORCPT ); Mon, 7 Sep 2015 08:33:14 -0400 Subject: Re: [PATCH v3 0/5] KVM: optimize userspace exits with a new ioctl To: Christian Borntraeger , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , linux-kernel@vger.kernel.org References: <1439546917-17391-1-git-send-email-rkrcmar@redhat.com> <55E6D009.9040000@de.ibm.com> Cc: kvm@vger.kernel.org From: Paolo Bonzini Message-ID: <55ED8407.8050703@redhat.com> Date: Mon, 7 Sep 2015 14:33:11 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <55E6D009.9040000@de.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/09/2015 12:31, Christian Borntraeger wrote: > As far as I can see this should also work for s390 (when we implement > REQ_EXIT handling) > > To double check my understanding: these improvements come with a changed > userspace that does not use KVM_SET_SIGNAL_MASK and therefore this > conditional is false > if (vcpu->sigset_active) > sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved); > Correct? > > That also means we improve exits that go to userspace but lightweight exits > that stay inside the kernel are not affected. Yes, both observations are correct. Paolo