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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 47F9DC43381 for ; Thu, 21 Mar 2019 14:37:34 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 BBDAA2077B for ; Thu, 21 Mar 2019 14:37:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BBDAA2077B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 44Q8Wv2gKLzDqTv for ; Fri, 22 Mar 2019 01:37:31 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=farosas@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 44Q8VG3fypzDqMN for ; Fri, 22 Mar 2019 01:36:06 +1100 (AEDT) Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x2LEXPaB062594 for ; Thu, 21 Mar 2019 10:36:04 -0400 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0b-001b2d01.pphosted.com with ESMTP id 2rc9fa136s-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 21 Mar 2019 10:36:03 -0400 Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 21 Mar 2019 14:35:56 -0000 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x2LEZu7I31260894 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 21 Mar 2019 14:35:57 GMT Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D0DA47805C; Thu, 21 Mar 2019 14:35:56 +0000 (GMT) Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 91AB278060; Thu, 21 Mar 2019 14:35:56 +0000 (GMT) Received: from localhost (unknown [9.86.27.221]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTPS; Thu, 21 Mar 2019 14:35:56 +0000 (GMT) From: Fabiano Rosas To: Alexey Kardashevskiy , kvm-ppc@vger.kernel.org Subject: Re: [RFC PATCH 1/1] KVM: PPC: Report single stepping capability In-Reply-To: References: <20190320183951.29537-1-farosas@linux.ibm.com> <20190320183951.29537-2-farosas@linux.ibm.com> Date: Thu, 21 Mar 2019 11:35:54 -0300 MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 x-cbid: 19032114-0016-0000-0000-000009957C96 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010789; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000281; SDB=6.01177580; UDB=6.00616030; IPR=6.00958277; MB=3.00026091; MTD=3.00000008; XFM=3.00000015; UTC=2019-03-21 14:35:59 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19032114-0017-0000-0000-00004287E69D Message-Id: <87va0ce1md.fsf@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-03-21_06:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=44 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=749 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1903210103 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kvm@vger.kernel.org, rkrcmar@redhat.com, pbonzini@redhat.com, linuxppc-dev@lists.ozlabs.org, david@gibson.dropbear.id.au Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Alexey Kardashevskiy writes: > In the cover letter (which is not really required for a single patch) > you say the capability will be present for BookE and PR KVM (which > Book3s) but here it is BookE only, is that intentional? A few lines below (falling through) we have: /* We support this only for PR */ r = !hv_enabled; > Also, you need to update Documentation/virtual/kvm/api.txt for the new > capability. After reading which I started wondering could not we just > use existing KVM_CAP_GUEST_DEBUG_HW_BPS? We _could_, but I think that would conflate two different concepts. Single stepping does not necessarily makes use of hardware breakpoints (e.g. Trace Interrupt on Book3s PR). I also think we should use KVM_CAP_GUEST_DEBUG_HW_BPS in the future to let QEMU know about: i) the lack of hardware breakpoints in Book3s and ii) BookE's hardware breakpoints (Instruction Address Compare) that are currently not being reported via HW_BPS.