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 D1F9CCD4851 for ; Wed, 13 May 2026 13:19:50 +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:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=zjT+vb/tDafLh2GigZV4tZznCDBCe+ymU+JxcHp7SLs=; b=xoD0HVQ8LqxgUJwekJ086OyJNF a4qI3Agz1g/3QlY+1fwtOtYORsDlGpD1pO0hyMfGP6KufTIRU7gpo1yQsb3cj+HSkXSZjRjpQVtDM dPDTqTpnZzOyC5elfbH9yTO7inW+/GrrKNd8jKSKeKe/Vhce8yxQvjssX9XWYbDViwuAZkgw9ANFO NPKboE7zu0hyMHh+IXuofuGklfhnbqPnBoZAIWYAtLuic8FEBJsU2OtJnUlUYub5LfHKdM6iT2xiw stfZKUdQkjR6lbRUGa4hkfATMDcqxbWdpmRqJPSIHIFk8W5cp0u1Qjq1KATdZErtL7XQls+YbA/Kr UYNOOofg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wN9V2-00000002fT8-3oyI; Wed, 13 May 2026 13:19:44 +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 1wN9Um-00000002f7t-1ioW for linux-arm-kernel@lists.infradead.org; Wed, 13 May 2026 13:19:41 +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 AA9072008; Wed, 13 May 2026 06:19:21 -0700 (PDT) Received: from e122027.arm.com (unknown [10.57.68.187]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BA97D3F836; Wed, 13 May 2026 06:19:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778678366; bh=XyhHOqSryuZS8p1TER/JzRvnrY9cIgXtR2qy2matUio=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NP1fuI5vArSoY8tcBBNDkh7PDlUfZDKSAYtGqS9ElXwZRsxGGZKFrevkbRJOzuOzY Jz1XKitDZYGTOT4lJ1Gv/RVkuq+4+DA8X/Rdd08stL3mbtX1YL8zIs8WhW+5FEjA4A U+OwtRTt1WUopk+mIt5HTM3gpyEWR4/r3375Kauw= From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun , "Aneesh Kumar K . V" , Emi Kisanuki , Vishal Annapurve , WeiLin.Chang@arm.com, Lorenzo.Pieralisi2@arm.com Subject: [PATCH v14 12/44] arm64: RMI: Check for LPA2 support Date: Wed, 13 May 2026 14:17:20 +0100 Message-ID: <20260513131757.116630-13-steven.price@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260513131757.116630-1-steven.price@arm.com> References: <20260513131757.116630-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260513_061928_613622_5C5CFA49 X-CRM114-Status: GOOD ( 12.06 ) 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 If KVM has enabled LPA2 support then check that the RMM also supports it. If there is a mismatch then disable support for realm guests as the VMM may attempt to create a guest which is incompatible with the RMM. Signed-off-by: Steven Price --- New patch for v13 --- arch/arm64/kvm/rmi.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/arm64/kvm/rmi.c b/arch/arm64/kvm/rmi.c index 1acc972a4b92..6e28b669ded2 100644 --- a/arch/arm64/kvm/rmi.c +++ b/arch/arm64/kvm/rmi.c @@ -5,9 +5,25 @@ #include +#include #include #include +static bool rmi_has_feature(unsigned long feature) +{ + return !!u64_get_bits(rmm_feat_reg0, feature); +} + +static int rmm_check_features(void) +{ + if (kvm_lpa2_is_enabled() && !rmi_has_feature(RMI_FEATURE_REGISTER_0_LPA2)) { + kvm_err("RMM doesn't support LPA2"); + return -ENXIO; + } + + return 0; +} + void kvm_init_rmi(void) { /* @@ -20,5 +36,8 @@ void kvm_init_rmi(void) if (!rmi_is_available()) return; + if (rmm_check_features()) + return; + /* Future patch will enable static branch kvm_rmi_is_available */ } -- 2.43.0