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=-6.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=no 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 43F3EC43464 for ; Mon, 21 Sep 2020 13:08:29 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C07B921789 for ; Mon, 21 Sep 2020 13:08:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="TyjLfs9I" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C07B921789 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49580 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kKLYR-0000dw-Lh for qemu-devel@archiver.kernel.org; Mon, 21 Sep 2020 09:08:27 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43724) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kKLXE-0008VF-Lb for qemu-devel@nongnu.org; Mon, 21 Sep 2020 09:07:12 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:48319) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kKLXD-0007LF-3M for qemu-devel@nongnu.org; Mon, 21 Sep 2020 09:07:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600693630; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=llsU2FQ3j6EzkrsurBg+jEiSMGoecRncjGgL5uSHvSs=; b=TyjLfs9IwztKwb0TjafiXdEZ2HEulbnH6gSBq8o0lt8w/ncyQMT9nvLM2ZVQX4xMheiujk aVJllxzE6OHpibaa13goLS/g3qiNW/98yvXKqIMtWHLVfRyqnoNuAyIroRvZJQOSGGQTt5 +3ANY1TQH/bWxE43J3Z2WeokGwNDFsg= 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-36-DAqmdOnpP0KExjVYCcHebQ-1; Mon, 21 Sep 2020 09:07:06 -0400 X-MC-Unique: DAqmdOnpP0KExjVYCcHebQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2CFFA801F95; Mon, 21 Sep 2020 13:07:05 +0000 (UTC) Received: from gondolin (unknown [10.40.192.53]) by smtp.corp.redhat.com (Postfix) with ESMTP id 962957366D; Mon, 21 Sep 2020 13:06:59 +0000 (UTC) Date: Mon, 21 Sep 2020 15:06:56 +0200 From: Cornelia Huck To: David Hildenbrand Subject: Re: [PATCH v2] s390x/tcg: Implement MONITOR CALL Message-ID: <20200921150656.0f2fcb81.cohuck@redhat.com> In-Reply-To: <20200918085122.26132-1-david@redhat.com> References: <20200918085122.26132-1-david@redhat.com> Organization: Red Hat GmbH MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=cohuck@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=63.128.21.124; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/21 01:44:53 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.455, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Thomas Huth , Christian Borntraeger , qemu-s390x@nongnu.org, Richard Henderson , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Fri, 18 Sep 2020 10:51:22 +0200 David Hildenbrand wrote: > Recent upstream Linux uses the MONITOR CALL instruction for things like > BUG_ON() and WARN_ON(). We currently inject an operation exception when > we hit a MONITOR CALL instruction - which is wrong, as the instruction > is not glued to specific CPU features. > > Doing a simple WARN_ON_ONCE() currently results in a panic: > [ 18.162801] illegal operation: 0001 ilc:2 [#1] SMP > [ 18.162889] Modules linked in: > [...] > [ 18.165476] Kernel panic - not syncing: Fatal exception: panic_on_oops > > With a proper implementation, we now get: > [ 18.242754] ------------[ cut here ]------------ > [ 18.242855] WARNING: CPU: 7 PID: 1 at init/main.c:1534 [...] > [ 18.242919] Modules linked in: > [...] > [ 18.246262] ---[ end trace a420477d71dc97b4 ]--- > [ 18.259014] Freeing unused kernel memory: 4220K > > Reported-by: Christian Borntraeger > Signed-off-by: David Hildenbrand > --- > > v1 -> v2: > - Simplify by not using the tb flags, always calling the helper. > > I looked into monitor-event counting, which looks easy at first glance > - but proper DAT/access exception handling is tricky. Leaving that for > a cold winter evening :) Fortunately, this is covered by a facility bit, so no need to do this now :) > > --- > target/s390x/excp_helper.c | 23 +++++++++++++++++++++++ > target/s390x/helper.h | 1 + > target/s390x/insn-data.def | 3 +++ > target/s390x/translate.c | 21 +++++++++++++++++++++ > 4 files changed, 48 insertions(+) Thanks, applied.