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=-7.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 35156C433DB for ; Tue, 2 Mar 2021 10:32:49 +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 CAEA660240 for ; Tue, 2 Mar 2021 10:32:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CAEA660240 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]:33154 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lH2Kd-0008Pe-Lu for qemu-devel@archiver.kernel.org; Tue, 02 Mar 2021 05:32:47 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:55918) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lH2Iq-0006Fb-C4 for qemu-devel@nongnu.org; Tue, 02 Mar 2021 05:30:56 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:47601) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1lH2Io-0001hq-GT for qemu-devel@nongnu.org; Tue, 02 Mar 2021 05:30:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614681053; h=from:from:reply-to: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=4ZAZadhor1emSlAHRqChAv4A0O66Z9g8ZhzfOgodE4U=; b=abyqU+IgA4FPBuxnhOLUaumUvmGVEYgs4zoYbXMbjQcjUlJjz1pJBo7aIl3FZohhkR5Fp6 fHamxfYWdFb6WO5pPxO/w7QO/26YUc+fDI6XX7BiST4acbdmQuYTu2VdUMhEnWCeh00+IC r8J5B3/qwQ1c11o8jRN7N/+SjRna+pI= 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-111-TkC6xGnsOte_vg6-C1KQdA-1; Tue, 02 Mar 2021 05:30:51 -0500 X-MC-Unique: TkC6xGnsOte_vg6-C1KQdA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9D28B1005501; Tue, 2 Mar 2021 10:30:50 +0000 (UTC) Received: from redhat.com (ovpn-113-132.ams2.redhat.com [10.36.113.132]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7201F1759F; Tue, 2 Mar 2021 10:30:49 +0000 (UTC) Date: Tue, 2 Mar 2021 10:30:46 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Daniele Buono Subject: Re: [PATCH v2 0/2] gitlab-ci.yml: Add jobs to test CFI Message-ID: References: <20210226152108.7848-1-dbuono@linux.vnet.ibm.com> <56d3d1a6-00af-1cc9-e980-748548191202@linux.vnet.ibm.com> <950b36a4-ec19-84df-9292-c88c390ce5fc@linux.vnet.ibm.com> MIME-Version: 1.0 In-Reply-To: <950b36a4-ec19-84df-9292-c88c390ce5fc@linux.vnet.ibm.com> User-Agent: Mutt/2.0.5 (2021-01-21) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Paolo Bonzini , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Mar 01, 2021 at 03:39:42PM -0500, Daniele Buono wrote: > Hi Daniel, > > On 3/1/2021 10:08 AM, Daniel P. Berrangé wrote: > > What are the unique failure scenarios for CFI that these jobs are > > likely to expose ? Is it likely that we'll have cases where > > CFI succeeds in say, x86_64 target, but fails in aarch64 target ? > > For CFI to fail (even if it shouldn't) you'll need code that is calling a > function pointer that was not well defined at compile time. Although > unlikely, that could happen everywhere in the code. What does "was not well defined" mean here ? > > So by just testing one (or few) targets we are are not covering the code in > the TCG frontend used to compile the target ISA to tcg ops, which should be > the in target/, and the architecture-dependent code in linux-user. > > That code seems unlikely (at least to me) to cause a false positive with > CFI. Examples that I've seen in QEMU so far are: > - Calling code that was JIT-ed at runtime > - Callbacks to functions that were loaded from shared libraries > - Signal Handlers > And none of those should happen there IMHO. But you know, corner cases are > still possible, and it's quite difficult to predict what new code may bring. > > We could also consider always testing one or two targets, and keep an > optional job to test them all when deemed necessary. I'm thinking for > example full testing when code in target/ or linux-user/ is considered, or > for testing pre-release code. Would be nice to have this automated but I am > not sure that's possible. > > Regards, > Daniele > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|