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 96196C88E7F for ; Wed, 16 Sep 2026 10:57:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=LGVXZUA+g62REzEChQK+lwmP5e863LfuKjlacn2KTRI=; b=jaDB6Ykv8xjDhqyTD/aV840Ych rZy6pyDsEAlHlwZYYsm0bcARNomqSEex1mPRQ19tHDDB8umay9zP8lxEwy0yMGKnOhBeSMVp+Q2Xp Pto9E5dFL1CE5dy3eN6hifEUkNMbtCvC4EYVeRKq8jTINddmkNDrERBXR661AIoWTJ046IP7+MYWg /lRB071DtzNGuspDDBVyXNpMd24O2KYdzJj/WjGI0Or5VtLjjJ28PBXwBeD657Jm1KUBhz2HsX8N+ aQ7hk167j4iXNcikV+8esN5TX8llynl9SIjGbsifiD2EXEeZgHxGYmQjs/W9K53MfF0Nfr/z5h59m Wuvix26A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x6nKR-000000091Ik-17Op; Wed, 16 Sep 2026 10:57:27 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x6nKP-000000091IK-1Qs3 for linux-arm-kernel@lists.infradead.org; Wed, 16 Sep 2026 10:57:26 +0000 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 05199152B; Wed, 16 Sep 2026 03:57:19 -0700 (PDT) Received: from arm.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6A8FF3F882; Wed, 16 Sep 2026 03:57:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1789556242; bh=5sS8Pv43xatXOJ2DntYftUU17HocoYWUvGVZRmaQXc8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jl/i1j2p1BX6BhBdjYRtagyYym1tFDsOw2ZvjpvW4sBBGK2hfgGcE5xfFemcxgGrZ tYLQoj0zI+daIGgWA8BUzAQe08huBUV6J1EQQL0HHMfhY/nOhYOE2c9GfcuPORFpgQ ab6D4JzJCZVKhcrhm9Zzeo1e1UuerEsN9kzJ07Ug= Date: Wed, 16 Sep 2026 11:57:17 +0100 From: Catalin Marinas To: "Aneesh Kumar K.V (Arm)" Cc: linux-coco@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Jason Gunthorpe , Greg KH , Jeremy Linton , Jonathan Cameron , Lorenzo Pieralisi , Mark Rutland , Sudeep Holla , Will Deacon , Steven Price , Suzuki K Poulose , Andre Przywara Subject: Re: [PATCH v11 7/7] coco: guest: arm64: Replace dummy CCA device with sysfs ABI Message-ID: References: <20260914060511.277948-1-aneesh.kumar@kernel.org> <20260914060511.277948-8-aneesh.kumar@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260914060511.277948-8-aneesh.kumar@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260916_035725_417879_6FBF0A40 X-CRM114-Status: GOOD ( 14.64 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Sep 14, 2026 at 11:35:11AM +0530, Aneesh Kumar K.V (Arm) wrote: > diff --git a/Documentation/ABI/testing/sysfs-firmware-cca b/Documentation/ABI/testing/sysfs-firmware-cca > new file mode 100644 > index 000000000000..bf177d636b92 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-firmware-cca > @@ -0,0 +1,10 @@ > +What: /sys/firmware/cca/realm_guest > +Date: May 2026 > +Contact: Linux ARM Kernel Mailing list > +Description: Read-only. Indicates whether the kernel is running as an > + Arm Confidential Compute Architecture (CCA) Realm guest. > + > + The value is one of: > + > + 0: the kernel is not running as a Realm guest > + 1: the kernel is running as a Realm guest Does this file ever read as 0? It is created only if rsi_present and always reads as 1. That's fine by me but we shouldn't document 0 as a value. More like if present, it always reads 1 and RSI is present. > diff --git a/drivers/firmware/arm_rmm/rsi.c b/drivers/firmware/arm_rmm/rsi.c > index 2dd69febedbd..52f40256bd78 100644 > --- a/drivers/firmware/arm_rmm/rsi.c > +++ b/drivers/firmware/arm_rmm/rsi.c > @@ -9,12 +9,15 @@ > #include > #include Nit: I think we can drop this include. -- Catalin