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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 6709BC433E6 for ; Wed, 2 Sep 2020 02:26:24 +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 C0EE52068F for ; Wed, 2 Sep 2020 02:26:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=ozlabs.org header.i=@ozlabs.org header.b="Lp+85cge" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C0EE52068F Authentication-Results: mail.kernel.org; dmarc=pass (p=none dis=none) header.from=ozlabs.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4Bh7994LzBzDqdt for ; Wed, 2 Sep 2020 12:26:21 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Bh76p4V5bzDqL9 for ; Wed, 2 Sep 2020 12:24:18 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=ozlabs.org Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=ozlabs.org header.i=@ozlabs.org header.a=rsa-sha256 header.s=201707 header.b=Lp+85cge; dkim-atps=neutral Received: by ozlabs.org (Postfix, from userid 1003) id 4Bh76p1Lpdz9sV8; Wed, 2 Sep 2020 12:24:18 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ozlabs.org; s=201707; t=1599013458; bh=EVixgcCRwMWQEliFU3rC3kvQfdu2zUDN7I19538RUFk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Lp+85cgesSbN4lHlJc86ML29C4qx3hCTYUlwbUvtWndDtjTon38aXbhOL4a+gPzEf zR/1jLvj6BaAqrcvn9oTJDo3SpVnGxm1Oxvy153U5wDdOXSRkHESwkIh0fxAx5yzL8 TNp0lEUzgCSR2pDRI+HFIfIGMv5MNYu8I4XdKL7rahf+F7ba3rU8h5wpa2dyjlOuKi XkdDBiyKjDWvSo0Ov+pX1oIWfz9hMw3fbvLeZ02D8Nc22Z3vwv/v6g4uqLKb3QgpLh IshWK5zmMDEuDL249XkM5xtdy279iAHHIM79WHP0HERuIc2a9p2i6U2RoHP/KFyuhp WPQ4Qlv/ifY6A== Date: Wed, 2 Sep 2020 12:01:24 +1000 From: Paul Mackerras To: Ravi Bangoria Subject: Re: [PATCH 2/7] powerpc/watchpoint/kvm: Add infrastructure to support 2nd DAWR Message-ID: <20200902020124.GB272502@thinks.paulus.ozlabs.org> References: <20200723102058.312282-1-ravi.bangoria@linux.ibm.com> <20200723102058.312282-3-ravi.bangoria@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200723102058.312282-3-ravi.bangoria@linux.ibm.com> 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: christophe.leroy@c-s.fr, mikey@neuling.org, rogealve@br.ibm.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, npiggin@gmail.com, kvm-ppc@vger.kernel.org, linux-kselftest@vger.kernel.org, jniethe5@gmail.com, pedromfc@br.ibm.com, pbonzini@redhat.com, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Thu, Jul 23, 2020 at 03:50:53PM +0530, Ravi Bangoria wrote: > kvm code assumes single DAWR everywhere. Add code to support 2nd DAWR. > DAWR is a hypervisor resource and thus H_SET_MODE hcall is used to set/ > unset it. Introduce new case H_SET_MODE_RESOURCE_SET_DAWR1 for 2nd DAWR. Is this the same interface as will be defined in PAPR and available under PowerVM, or is it a new/different interface for KVM? > Also, kvm will support 2nd DAWR only if CPU_FTR_DAWR1 is set. In general QEMU wants to be able to control all aspects of the virtual machine presented to the guest, meaning that just because a host has a particular hardware capability does not mean we should automatically present that capability to the guest. In this case, QEMU will want a way to control whether the guest sees the availability of the second DAWR/X registers or not, i.e. whether a H_SET_MODE to set DAWR[X]1 will succeed or fail. Paul.