From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 22D1B48AE04; Wed, 15 Jul 2026 14:31:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784125882; cv=none; b=aC4/kX+dwqZOAHKB+GshkRMpVyclqmF2CywDkTEVCUzMTch5nzTsm4i0GUoUu5MFxuz+Cos+u+Qgywqy/kAUkeDda1njJjL8BpcAcnTsXsbqaE0y8jNz3IkAjPIetkV44IXgTVEtPP1CYc94F/Bx57Jbgs/F5MhYSP2dMUw/d7U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784125882; c=relaxed/simple; bh=/DkC06ykICbYbu8lRH1puAEPBlPtvdphP1WP+AibYYM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JZBObCJf0YQAJFGlmY19+lEFDiUc+SUbVUPv5yaBcGYNzofAaS5gpHbOqO31Fv6tmAl9/JRIqmxlMjBRK34Rrafk0MvUThQenp6D05jUzkenBZ90Hozjy2Vn3NCOJ96dqKgZg1z+FWSx942EyzYt69FVXARYXVakp1RQh11WtyA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=Mkfra4+I; arc=none smtp.client-ip=217.140.110.172 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) header.d=arm.com header.i=@arm.com header.b="Mkfra4+I" 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 EA18F15A1; Wed, 15 Jul 2026 07:31:12 -0700 (PDT) Received: from e122027.cambridge.arm.com (e122027.cambridge.arm.com [10.1.25.27]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0459F3F7B4; Wed, 15 Jul 2026 07:31:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1784125877; bh=/DkC06ykICbYbu8lRH1puAEPBlPtvdphP1WP+AibYYM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Mkfra4+IcJ0yxokQd4mwR1MWgWfiDKuRjdn49nomVQc2bK/inpRfIaPDYkzt+wEGh 7B7RSCiauG7iw7RB6PQODvm29CUcIkOmXG4etFnbVhdGgBGjlq3jIuksREVyCNI+O9 tWqm6qMaCmwG1cPaXPwJN6sUlxr/7/BljXrsDKxs= 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 Pieralisi Subject: [PATCH v15 30/37] KVM: arm64: CCA: Prevent Device mappings for realms Date: Wed, 15 Jul 2026 15:28:32 +0100 Message-ID: <20260715142841.80544-31-steven.price@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260715142841.80544-1-steven.price@arm.com> References: <20260715142841.80544-1-steven.price@arm.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Physical device assignment is not yet supported. RMM v2.0 does add the relevant APIs, but device assignment is a big topic so will be handled in a future patch series. For now prevent device mappings when the guest is a realm. Signed-off-by: Steven Price --- Changes from v6: * Fix the check in user_mem_abort() to prevent all pages that are not guest_memfd() from being mapped into the protected half of the IPA. Changes from v5: * Also prevent accesses in user_mem_abort() --- arch/arm64/kvm/mmu.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 79119cb136b0..dc27f3dfb337 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1261,6 +1261,10 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, if (is_protected_kvm_enabled()) return -EPERM; + /* We don't support mapping special pages into a Realm */ + if (kvm_is_realm(kvm)) + return -EPERM; + size += offset_in_page(guest_ipa); guest_ipa &= PAGE_MASK; -- 2.43.0