From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 117F3C48BE5 for ; Mon, 21 Jun 2021 14:34:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3214610CA for ; Mon, 21 Jun 2021 14:34:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230388AbhFUOgv (ORCPT ); Mon, 21 Jun 2021 10:36:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:45139 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230377AbhFUOgu (ORCPT ); Mon, 21 Jun 2021 10:36:50 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624286075; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=r2IzcWriMhbCMjmWDwaupeM2bjpacjY5rwsJcIHZVPo=; b=emGY+YZxMN1tZI03PkKfn1MC080cjE1+jozAOIPRPhalj9MP7LLT/PF4hYMsiPTuxoI9JI pZU+OPYFmkA2kqVhtc0eh4zz0xsPC1PfL6iPqF+m8p4ZAQ3RwsIXj2HhEYLb+iOTfpOt9A xy8otyLzUJNe3iHIA442aJpNi8e8RXA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-218-VP3ZP_i2MD6mb8kqXM-z6w-1; Mon, 21 Jun 2021 10:34:33 -0400 X-MC-Unique: VP3ZP_i2MD6mb8kqXM-z6w-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 14A12802C80; Mon, 21 Jun 2021 14:34:32 +0000 (UTC) Received: from localhost (ovpn-113-141.ams2.redhat.com [10.36.113.141]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7336E10013D6; Mon, 21 Jun 2021 14:34:28 +0000 (UTC) From: Cornelia Huck To: Heiko Carstens , Christian Borntraeger , Janosch Frank Cc: David Hildenbrand , Claudio Imbrenda , kvm@vger.kernel.org, linux-s390@vger.kernel.org Subject: Re: [PATCH] KVM: s390: get rid of register asm usage In-Reply-To: <20210621140356.1210771-1-hca@linux.ibm.com> Organization: Red Hat GmbH References: <20210621140356.1210771-1-hca@linux.ibm.com> User-Agent: Notmuch/0.32.1 (https://notmuchmail.org) Date: Mon, 21 Jun 2021 16:34:26 +0200 Message-ID: <87sg1bnv65.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org %On Mon, Jun 21 2021, Heiko Carstens wrote: > Using register asm statements has been proven to be very error prone, > especially when using code instrumentation where gcc may add function > calls, which clobbers register contents in an unexpected way. > > Therefore get rid of register asm statements in kvm code, even though > there is currently nothing wrong with them. This way we know for sure > that this bug class won't be introduced here. > > Reviewed-by: Christian Borntraeger > Signed-off-by: Heiko Carstens > --- > arch/s390/kvm/kvm-s390.c | 18 +++++++++--------- > 1 file changed, 9 insertions(+), 9 deletions(-) Reviewed-by: Cornelia Huck