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 88AA4C4332F for ; Fri, 30 Sep 2022 12:09:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231326AbiI3MJf (ORCPT ); Fri, 30 Sep 2022 08:09:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230095AbiI3MJb (ORCPT ); Fri, 30 Sep 2022 08:09:31 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CA1416DDDA; Fri, 30 Sep 2022 05:09:30 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id EE25162310; Fri, 30 Sep 2022 12:09:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D16C0C433D6; Fri, 30 Sep 2022 12:09:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1664539769; bh=MWCtz2Oh25qxLNuhpkJKCw4gaTdEGebqCTQSJg72jCE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=br5SPY0F2q7MBD4j0OrfokYZfjLETE4GiFjBlN5gFBjrk6jwz4ffY78fW4m3KaY2d LHuyvpQNHtefH/T3Mxxb0FiBHtLS2lPvaTh+o4oV49GjaexQZ82LZEC0yop6kY7e7o ENNRO3lnKpl/G5snSIeDUd2Wr46bCzzTj3N1Kpqo= Date: Fri, 30 Sep 2022 14:09:27 +0200 From: Greg Kroah-Hartman To: Elliot Berman Cc: Bjorn Andersson , Murali Nalajala , Trilok Soni , Srivatsa Vaddagiri , Carl van Schaik , Andy Gross , Dmitry Baryshkov , Jassi Brar , linux-arm-kernel@lists.infradead.org, Mark Rutland , Lorenzo Pieralisi , Sudeep Holla , Marc Zyngier , Rob Herring , Krzysztof Kozlowski , Jonathan Corbet , Will Deacon , Catalin Marinas , Arnd Bergmann , devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 06/14] virt: gunyah: Add sysfs nodes Message-ID: References: <20220928195633.2348848-1-quic_eberman@quicinc.com> <20220928195633.2348848-7-quic_eberman@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220928195633.2348848-7-quic_eberman@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 28, 2022 at 12:56:25PM -0700, Elliot Berman wrote: > Add /sys/hypervisor support when detecting that Linux is running in a > Gunyah environment. Export the version of Gunyah which is reported via > the hyp_identify hypercall. > > Signed-off-by: Elliot Berman > --- > .../ABI/testing/sysfs-hypervisor-gunyah | 15 ++++ > MAINTAINERS | 1 + > drivers/virt/Makefile | 1 + > drivers/virt/gunyah/Makefile | 2 + > drivers/virt/gunyah/sysfs.c | 71 +++++++++++++++++++ > 5 files changed, 90 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-hypervisor-gunyah > create mode 100644 drivers/virt/gunyah/Makefile > create mode 100644 drivers/virt/gunyah/sysfs.c > > diff --git a/Documentation/ABI/testing/sysfs-hypervisor-gunyah b/Documentation/ABI/testing/sysfs-hypervisor-gunyah > new file mode 100644 > index 000000000000..7d74e74e9edd > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-hypervisor-gunyah > @@ -0,0 +1,15 @@ > +What: /sys/hypervisor/gunyah/api > +Date: October 2022 > +KernelVersion: 6.1 > +Contact: linux-arm-msm@vger.kernel.org > +Description: If running under Gunyah: > + The Gunyah API version. What does this version mean? What format is it in? > + > +What: /sys/hypervisor/gunyah/variant > +Date: October 2022 > +KernelVersion: 6.1 > +Contact: linux-arm-msm@vger.kernel.org > +Description: If running under Gunyah: > + Reports the build variant of Gunyah: > + The open source build of Gunyah will report "81". > + The Qualcomm build of Gunyah will report "72". So there are only 2 versions variants? What happens when you get a third? And why the odd numbers? What will userspace do with this information and what tool will parse it? > diff --git a/MAINTAINERS b/MAINTAINERS > index feafac12db35..a26e67ef36b4 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -8885,6 +8885,7 @@ M: Elliot Berman > M: Murali Nalajala > L: linux-arm-msm@vger.kernel.org > S: Supported > +F: Documentation/ABI/testing/sysfs-hypervisor-gunyah > F: Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml > F: Documentation/virt/gunyah/ > F: arch/arm64/gunyah/ > diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile > index 093674e05c40..10b87f934730 100644 > --- a/drivers/virt/Makefile > +++ b/drivers/virt/Makefile > @@ -11,3 +11,4 @@ obj-$(CONFIG_NITRO_ENCLAVES) += nitro_enclaves/ > obj-$(CONFIG_ACRN_HSM) += acrn/ > obj-$(CONFIG_EFI_SECRET) += coco/efi_secret/ > obj-$(CONFIG_SEV_GUEST) += coco/sev-guest/ > +obj-$(CONFIG_GUNYAH) += gunyah/ > diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile > new file mode 100644 > index 000000000000..e15f16c17142 > --- /dev/null > +++ b/drivers/virt/gunyah/Makefile > @@ -0,0 +1,2 @@ > +gunyah-y += sysfs.o > +obj-$(CONFIG_GUNYAH) += gunyah.o > diff --git a/drivers/virt/gunyah/sysfs.c b/drivers/virt/gunyah/sysfs.c > new file mode 100644 > index 000000000000..ec11510cbece > --- /dev/null > +++ b/drivers/virt/gunyah/sysfs.c > @@ -0,0 +1,71 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#define pr_fmt(fmt) "gunyah: " fmt > + > +#include > +#include > +#include > +#include > +#include > + > +static struct gh_hypercall_hyp_identify_resp gunyah_api; > + > +static ssize_t api_show(struct kobject *kobj, struct kobj_attribute *attr, char *buffer) > +{ > + return sysfs_emit(buffer, "%d\n", (int)GH_API_INFO_API_VERSION(gunyah_api.api_info)); > +} > +static struct kobj_attribute api_attr = __ATTR_RO(api); > + > +static ssize_t variant_show(struct kobject *kobj, struct kobj_attribute *attr, char *buffer) > +{ > + return sysfs_emit(buffer, "%d\n", (int)GH_API_INFO_VARIANT(gunyah_api.api_info)); > +} > +static struct kobj_attribute variant_attr = __ATTR_RO(variant); > + > +static struct attribute *gunyah_attrs[] = { > + &api_attr.attr, > + &variant_attr.attr, > + NULL > +}; > + > +static const struct attribute_group gunyah_group = { > + .name = "gunyah", > + .attrs = gunyah_attrs, > +}; > + > +static int __init gunyah_init(void) > +{ > + u32 uid[4]; > + > + gh_hypercall_get_uid(uid); No error checking? > + > + if (!(gh_uid_matches(GUNYAH, uid) || gh_uid_matches(QC_HYP, uid))) > + return 0; > + > + gh_hypercall_hyp_identify(&gunyah_api); > + > + if (GH_API_INFO_API_VERSION(gunyah_api.api_info) != 1) { > + pr_warn("Unrecognized gunyah version: %llu. Currently supported: 1\n", > + GH_API_INFO_API_VERSION(gunyah_api.api_info)); Shouldn't the "1" be defined somewhere? > + return 0; > + } > + > + pr_notice("Running under Gunyah hypervisor %llx/v%lld\n", > + GH_API_INFO_VARIANT(gunyah_api.api_info), > + GH_API_INFO_API_VERSION(gunyah_api.api_info)); When kernel code is working properly, it is quiet. What is this going to be used for? thanks, greg k-h