From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.140.110.172 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792675048; b=e9178iE/GHVCYoDpLG8eNNaQcg5cxV2G9sTnD6RwocL+UqgbBrxghqtY4+Iu3rcKzdAC I9U3htwrJIrpEcZlekkeK1XOXJNbs6AUNm1GXTk6P6528eWdAbQMx+aR4xiyERkVqZH2M bjjT7c1BG/7Mx2lk+LZPBKBfL340OVD04+X1gx2eMvaJvFFZtz+THlqKBAfhBcpoSGiqh 4fd2ezQhwfgGBt9MZJb2s7GCcrxeJ3gbgacTBwZhCflPoxAQaS3msCECxbLFam2bAwfoc DtfZyw7kREQXFhLE4zOaxgLYRwTKqKWQEXRQcwJy02ev06IZQgbFIpM96z8g23mY6bw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792675048; h=DMARC-Filter:Received:Received:DKIM-Signature:Date:From:To:Cc: Subject:Message-ID:References:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; bh=eQf4Ux3KgpPvYJ/vZ/XrAxGRYNkjOFHzjKZYgsvPaUA=; b=JNdCUv56a75gZSnrytR2xQ0lKH0pOhnda25H6POO3fsR439W6XOWG/hvEzEx0IWnxzxr zPC6Enasc7BVtaZo8HPQNMlLFQD9fG7vueo6SX2oPbzjSEhHloueTSQNzhd0wbdSk23Qt 4pgKojcMx1ooJHy6uGL5LmB/XSodP709NAY5s/zlSR70CTORE2NsQJuucEkJSdBjtrtCm 9811lxcyx+5Bi1WXjo6BKuwwUNZCkayCAYfEF850a2hV4BZ3V3JytdkoY8H02UG7u2jqI +BHq51Iog6mJaSCYDBh8M0FAbS6rge2WEGh75Gq/syaV/4l69r+ZJdumXhmwKcTsLkA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=kaMcGbEQ; arc=none smtp.remote-ip=217.140.110.172 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 52094606A31A for ; Thu, 22 Oct 2026 13:17:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 52094606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=kaMcGbEQ 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 541412C34; Thu, 22 Oct 2026 06:17:24 -0700 (PDT) Received: from e129823.arm.com (e129823.arm.com [10.2.213.3]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8CAB13F673; Thu, 22 Oct 2026 06:17:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1792675047; bh=0s7bfEvTJgNfIljZiLJWu7OAwfMP+SubhPZFX3IkXwQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kaMcGbEQxmy0Ec8g7NLwAJplIEgN0KZqDZ25nJ9T+y9vCYjJMo4N09+X/gtUyZjEB QaI8BY1cstU+Ae4jAhbmNYNh9x9UWMtawAEkMuKUfaokNLXw9ksxMfZq8wYGR9x+Zv eqVWgSjmgDaE+Lukag3OFgdzIjpd/YkWqjS5jn/A= Date: Thu, 22 Oct 2026 14:17:23 +0100 From: Yeoreum Yun To: Kohei Enju Cc: Yeoreum Yun , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Lorenzo Pieralisi , Catalin Marinas , Suzuki Poulose , Steven Price , Sami Mujawar , "Aneesh Kumar K.V" , Jiri Pirko , GONG Ruiqi , Jason Gunthorpe Subject: Re: [PATCH RFC 1/3] firmware: arm_firme: introduce arm_firme driver Message-ID: References: <20261019-firme_interface-v1-0-27895c9cebaa@arm.com> <20261019-firme_interface-v1-1-27895c9cebaa@arm.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Oct 22, 2026 at 06:48:49PM +0900, Kohei Enju wrote: > On 10/19 15:14, Yeoreum Yun wrote: > > The Realm Management Extension (FEAT_RME) is part of Arm Confidential > > Compute Architecture (CCA) and enables support for dynamic, attestable > > trusted execution environments ("Realms") on Arm systems. > > > > Realm management flows depend on EL3 firmware for operations such as > > Realm construction, resource allocation and isolation, and attestation > > of initial Realm state. > > > > The FIRME defines standard interfaces provided by EL3 firmware to > > satisfy these dependencies. These interfaces include: > > > > - Granule Protection Table management > > - IDE key management for PCIe and CXL Root Ports > > - Memory Encryption Context management > > - Attestation token management > > - Integrated device management > > > > Each group of interfaces forms a FIRME service. A base FIRME service > > is also defined to provide common concepts, service discovery, and > > feature discovery across services. > > > > FIRME interfaces are implemented at the EL3 boundary between the > > Non-secure, Realm, and Secure states. They may also be used on systems > > without FEAT_RME, for example to provide firmware-based attestation or > > security services. > > > > arm_firme driver provides the common FIRME framework and service discovery > > support for client drivers using below FIRME services: > > > > - Base service. > > - Attestation token management. > > > > Signed-off-by: Yeoreum Yun > > Does this series assume that the kernel is running in EL2 implicitly? > > The FIRME spec says: > An implementation of one or more FIRME services at a valid Exception level boundary between EL3 and the > highest Exception level in a different Security state is called a FIRME instance. > > and I think only NS-EL2 can call FIRME interfaces as a NS FIRME > instance, right? Yeap. but it doens't forbid calling the FIRME from EL1 too. As a just example, when the host running with pkvm, it could use where kernel running as EL1. [...] -- Sincerely, Yeoreum Yun