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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5DCECEB64DD for ; Sat, 5 Aug 2023 10:15:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229743AbjHEKO6 (ORCPT ); Sat, 5 Aug 2023 06:14:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229477AbjHEKOy (ORCPT ); Sat, 5 Aug 2023 06:14:54 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 1841646B2 for ; Sat, 5 Aug 2023 03:14:50 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1E5BE1FB; Sat, 5 Aug 2023 03:15:32 -0700 (PDT) Received: from [10.57.90.200] (unknown [10.57.90.200]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A5BD03F5A1; Sat, 5 Aug 2023 03:14:46 -0700 (PDT) Message-ID: <63e20343-b95c-308f-ac43-8285ef164caf@arm.com> Date: Sat, 5 Aug 2023 11:14:45 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [RFC PATCH 0/3] coresight: Support exclude_guest with Feat_TRF and nVHE To: James Clark , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Cc: Marc Zyngier , Oliver Upton , James Morse , Zenghui Yu , Catalin Marinas , Will Deacon , Mike Leach , Leo Yan , Alexander Shishkin , Anshuman Khandual , Rob Herring , linux-kernel@vger.kernel.org, Steve Clevenger , Tanmay Jagdale , Ganapatrao Kulkarni References: <20230804101317.460697-1-james.clark@arm.com> From: Suzuki K Poulose In-Reply-To: <20230804101317.460697-1-james.clark@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Cc: Ganpatrao, Steve, Tanmay On 04/08/2023 11:13, James Clark wrote: > Hi, > > I'm looking for help in testing this and for feedback on whether it's > useful to anyone. Testing it requires hardware that has Feat_TRF (v8.4) > but no TRBE. This is because TRBE usage is disabled in nVHE guests. > > I don't currently have any access to any hardware, and the FVP model > can only do self hosted trace using TRBE. If you have a v8.4+ (and not v9) HW, please could you give this a spin ? Suzuki > > Currently with nVHE you would always get trace from guests, and > filtering out isn't possible without this patchset. In comparison, with > VHE guests, they never generate guest trace without [1]. I think the > existence of trace rather than lack of could suggest that this change is > less useful than [1]. Also the restricted set of hardware that it works > on supports that too. > > Apart from compilation and checking that the exclude guest settings > are correctly programmed on guest switch, this is untested by me. > > Applies to kvmarm/next (3b4e3afb2032) > > [1]: https://lore.kernel.org/linux-arm-kernel/20230804085219.260790-3-james.clark@arm.com/ > > James Clark (3): > arm64: KVM: Add support for exclude_guest and exclude_host for ETM > arm64: KVM: Support exclude_guest for Coresight trace in nVHE > coresight: Support exclude_guest with Feat_TRF and nVHE > > arch/arm64/include/asm/kvm_host.h | 10 +++- > arch/arm64/kvm/Makefile | 1 + > arch/arm64/kvm/arm.c | 1 + > arch/arm64/kvm/debug.c | 7 +++ > arch/arm64/kvm/etm.c | 48 ++++++++++++++++ > arch/arm64/kvm/hyp/nvhe/debug-sr.c | 56 +++++++++++++++++-- > .../hwtracing/coresight/coresight-etm-perf.c | 4 ++ > include/kvm/etm.h | 43 ++++++++++++++ > 8 files changed, 165 insertions(+), 5 deletions(-) > create mode 100644 arch/arm64/kvm/etm.c > create mode 100644 include/kvm/etm.h >