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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D299CC433FE for ; Tue, 4 Oct 2022 23:54:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:References:CC:To:Subject:From: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=PMQS+mQD2EY3XI8rDfPUM0Y3bG6angC94CrDnFAELfo=; b=LYBzDTs0g7EExI E62jryhBas7qOyOS8W9kayIuQI+ICX9GueQBmj6vtzQCNR3+5z4TVP767b887R0I7FkYDThwMTirQ Z6UiLQUCxbf+STYivDDvuMg05ge6R+Fx0cAgdiiN2NzZ9XLpnDruBfW5eInHXRCzE5tq8e7CpaIYp Gz/BQm2vbkiTZUNK7fM5JMQbva7jALq/XiU0GEC0P8K7q7c4PClaanfYYVHQuDK/zrGggWBmSPXhw h7qE1lCPyfqkWOR6xi8J9e6KBfxxc5nCQR0Mno718i0jB65lT4wS4i1A75rq9QzmvMlQSPr/m9N2v 0U6eD0Nb/CIdy6l5WKlw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ofrjS-00Bb9J-22; Tue, 04 Oct 2022 23:53:52 +0000 Received: from mx0b-0031df01.pphosted.com ([205.220.180.131]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ofrjO-00Bb7L-Ln for linux-arm-kernel@lists.infradead.org; Tue, 04 Oct 2022 23:53:48 +0000 Received: from pps.filterd (m0279871.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 294NjQZN021822; Tue, 4 Oct 2022 23:53:36 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=message-id : date : mime-version : from : subject : to : cc : references : in-reply-to : content-type : content-transfer-encoding; s=qcppdkim1; bh=7sIaGt5RW6txQtkzPaHVb28p1gFIFEWXixdkRB8Zcys=; b=ozcZqgsI5PZE8TxZbC7nq2S/U4nr0+50sJGzgMRifBnu1MwP7KmkSodRynPLPBZzZE/m 4bz9uco0MYliO4hWRa+3ZC0qi9fDh1up4/kBPCv42P6ttxHCJdtNzO583TQvqlf5z0vn 4hP48dUV9IVP+7Vvc/ITvjXRfMnJeCbSq8ArORs8bMn3mrZeg79XGJqvatHkn+prsreD 8P+2tyCfSyc+ByOj157qClVhtRnu1uZds1xTtkvLkSgPGJXcOVgFFYfgdihlxdXteaIf cn/9ZJct6NUxUHIAiABXjgtnEuTlNKBS816lL1zXZUtjUCINyQy6Vu4ukq5viz6u8iWW 3g== Received: from nasanppmta04.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3k0syqrg7v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 04 Oct 2022 23:53:36 +0000 Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA04.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 294NrZYA009612 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 4 Oct 2022 23:53:35 GMT Received: from [10.110.114.145] (10.80.80.8) by nasanex01b.na.qualcomm.com (10.46.141.250) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.29; Tue, 4 Oct 2022 16:53:34 -0700 Message-ID: <7f161062-fe7a-05a0-2719-c92ab58f5ac6@quicinc.com> Date: Tue, 4 Oct 2022 16:53:33 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 From: Elliot Berman Subject: Re: [PATCH v4 10/14] gunyah: sysfs: Add node to describe supported features To: Greg Kroah-Hartman CC: Bjorn Andersson , Murali Nalajala , Trilok Soni , "Srivatsa Vaddagiri" , Carl van Schaik , Andy Gross , Dmitry Baryshkov , Jassi Brar , , Mark Rutland , Lorenzo Pieralisi , Sudeep Holla , Marc Zyngier , Rob Herring , Krzysztof Kozlowski , Jonathan Corbet , "Will Deacon" , Catalin Marinas , "Arnd Bergmann" , , , , References: <20220928195633.2348848-1-quic_eberman@quicinc.com> <20220928195633.2348848-11-quic_eberman@quicinc.com> Content-Language: en-US In-Reply-To: X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nasanex01b.na.qualcomm.com (10.46.141.250) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: DYtvgx6IWL7muc7U4wXzwIhgWLIMmbuw X-Proofpoint-ORIG-GUID: DYtvgx6IWL7muc7U4wXzwIhgWLIMmbuw X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-10-04_09,2022-09-29_03,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxlogscore=822 mlxscore=0 phishscore=0 impostorscore=0 suspectscore=0 adultscore=0 spamscore=0 bulkscore=0 lowpriorityscore=0 priorityscore=1501 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2209130000 definitions=main-2210040153 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221004_165346_867115_B49B7561 X-CRM114-Status: GOOD ( 24.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 9/30/2022 5:06 AM, Greg Kroah-Hartman wrote: > On Wed, Sep 28, 2022 at 12:56:29PM -0700, Elliot Berman wrote: >> Add a sysfs node to list the features that the Gunyah hypervisor and >> Linux supports. For now, Linux support cspace (capability IDs) and >> message queues, so only report those.. >> >> Signed-off-by: Elliot Berman >> --- >> Documentation/ABI/testing/sysfs-hypervisor-gunyah | 15 +++++++++++++++ >> drivers/virt/gunyah/sysfs.c | 15 +++++++++++++++ >> 2 files changed, 30 insertions(+) >> >> diff --git a/Documentation/ABI/testing/sysfs-hypervisor-gunyah b/Documentation/ABI/testing/sysfs-hypervisor-gunyah >> index 7d74e74e9edd..6d0cde30355a 100644 >> --- a/Documentation/ABI/testing/sysfs-hypervisor-gunyah >> +++ b/Documentation/ABI/testing/sysfs-hypervisor-gunyah >> @@ -1,3 +1,18 @@ >> +What: /sys/hypervisor/gunyah/features >> +Date: October 2022 >> +KernelVersion: 6.1 >> +Contact: linux-arm-msm@vger.kernel.org >> +Description: If running under Gunyah: >> + Space separated list of features supported by Linux and Gunyah: >> + "cspace": Gunyah devices >> + "doorbell": Sending/receiving virtual interrupts via Gunyah doorbells >> + "message-queue": Sending/receiving messages via Gunyah message queues >> + "vic": Interrupt lending >> + "vpm": Virtual platform management >> + "vcpu": Virtual CPU management >> + "memextent": Memory lending/management >> + "trace": Gunyah hypervisor tracing > > Please no. Why do you really need this type of list? What hypervisor > will NOT have them all present already? Who will use this file and what > will it be used for? > > sysfs files should just be 1 value and not need to be parsed. Yes, we > have lists of features at times, but really, you need a very very good > reason why this is the only way this information can be exposed and who > is going to use it in order to be able to have this accepted. > We're currently at phase where all the features implemented so far as considered part of the "base" featureset. We're thinking of future features implemented in Gunyah: userspace might need to know that some hypervisor feature is present and that it should make use of the feature instead of some fallback behavior. I can drop this and it should be OK IMO to introduce it later if needed. The lack of the "gunyah/features" node would be sufficient for a userspace program to know that some new feature isn't present. > thanks, > > greg k-h _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel