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 7ACA2CD5BA4 for ; Tue, 19 May 2026 12:56:12 +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-Type:MIME-Version: Message-ID:Date:References:In-Reply-To:Subject:Cc:To:From: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=hby3knI6Udl+KWoq6fqUYnqbIp0KJ9sKrYAdgqVYUi0=; b=aH6iOhRpVRoZfC9yPbOQgpKZHq jDXSH5COToSiRvcYn8JmK9E5jkQ3Xo4eHaJPXU4q87+JuG13r9sk42TurtLsUuGZhV/2njF6pzTpN BJvYkmYm5MlioRjQDk1hM0tMhoJ+zI+FiedFEtWQGxn66UlAV1HU/AE7lKMnB2GoJ+TWcHjuqES7p ZxWykfca4BBSUyE27Rhl2Pt58CRONWCwRlxNpdHoUeT8V8mBZaEyTIY1YIEKiY33TUc/LQKP8yPBu J2N8Rr/VSMhH2FTUQzSecpA4hcI1RKREKoqEoK4X+seBsRCHGUO8FbgptRdpZJk3Y/lMGCTnYbutD 8m/tMWwA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wPJzR-00000001YXE-0DhZ; Tue, 19 May 2026 12:56:05 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wPJzP-00000001YWY-0tK2 for linux-arm-kernel@lists.infradead.org; Tue, 19 May 2026 12:56:04 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id A6D59406D7; Tue, 19 May 2026 12:56:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D9A4C2BCB3; Tue, 19 May 2026 12:55:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779195362; bh=Xfxs9VwhdJKne3gTf8HJ94QxvyAL3Oe1auKr7Ait+AI=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=PFYn2EQI6o67e3QXj1DmucFzY5eMUMVymfs8SWHXncySGE4NzDUggvInLFr6ixsxt qYg0twpu4rJ6zwcv2EkrCHFLnYMtZXbPyPGyQp7J8y6uStLkA66YZkf9TMjMAtB0R7 gwC3eSMHnmV+sx9T9KrsuVPkn2Peyno2mWDGmAhKcSD1ZXmBVlfxMa6QQVn42RIznn 3OIPR8CO0/7k0gkobMUa7ZtA/zloHi04HmIUPdroRaX/R0/MQws3I14tk74bCHstbG fo2NHacy3VzbZSO2K5OYkAyPm4uD8SVAWH28rdJeyJFPUhYvBk77tTXkmsWtJMuJ1E 51FQMMQt4xrcw== X-Mailer: emacs 30.2 (via feedmail 11-beta-1 I) From: Aneesh Kumar K.V To: Suzuki K Poulose , Steven Price , kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , 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 , Emi Kisanuki , Vishal Annapurve , WeiLin.Chang@arm.com, Lorenzo.Pieralisi2@arm.com Subject: Re: [PATCH v14 27/44] arm64: RMI: Set RIPAS of initial memslots In-Reply-To: <6681f10b-0966-42e2-ae04-4e1aef47ec4d@arm.com> References: <20260513131757.116630-1-steven.price@arm.com> <20260513131757.116630-28-steven.price@arm.com> <6681f10b-0966-42e2-ae04-4e1aef47ec4d@arm.com> Date: Tue, 19 May 2026 18:25:52 +0530 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260519_055603_298145_308D3CDB X-CRM114-Status: GOOD ( 18.87 ) 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 Suzuki K Poulose writes: > On 19/05/2026 11:02, Aneesh Kumar K.V wrote: >> Steven Price writes: >> >>> The memory which the realm guest accesses must be set to RIPAS_RAM. >>> Iterate over the memslots and set all gmem memslots to RIPAS_RAM. >>> >>> Signed-off-by: Steven Price >>> --- >> >> ... >> >>> +static int set_ripas_of_protected_regions(struct kvm *kvm) >>> +{ >>> + struct kvm_memslots *slots; >>> + struct kvm_memory_slot *memslot; >>> + int idx, bkt; >>> + int ret = 0; >>> + >>> + idx = srcu_read_lock(&kvm->srcu); >>> + >>> + slots = kvm_memslots(kvm); >>> + kvm_for_each_memslot(memslot, bkt, slots) { >>> + if (!kvm_slot_has_gmem(memslot)) >>> + continue; >>> + >>> + ret = realm_init_ipa_state(kvm, memslot->base_gfn, >>> + memslot->npages); >>> + if (ret) >>> + break; >>> + } >>> + srcu_read_unlock(&kvm->srcu, idx); >>> + >>> + return ret; >>> +} >>> + >>> int kvm_arm_rmi_populate(struct kvm *kvm, >>> struct kvm_arm_rmi_populate *args) >>> { >>> @@ -890,6 +922,10 @@ int kvm_activate_realm(struct kvm *kvm) >>> return ret; >>> } >>> >>> + ret = set_ripas_of_protected_regions(kvm); >>> + if (ret) >>> + return ret; >>> + >>> ret = rmi_realm_activate(virt_to_phys(realm->rd)); >>> if (ret) >>> return -ENXIO; >> >> relam guest already does. >> for_each_mem_range(i, &start, &end) { >> if (rsi_set_memory_range_protected_safe(start, end)) { >> panic("Failed to set memory range to protected: %pa-%pa", >> &start, &end); >> } >> } >> >> if so why is host required to do this ? > > Ideally this should be a call from the VMM (i.e., user). Irrespective of > what the guest does (which the host has no knowledge about), the VMM/ > user is better aware of what to do for a given guest. We have done this > implicitly in the KVM as a start, to keep the initial implementation > simple. This could be moved out to the VMM as UABI, if there is > sufficient demand for it. > > TL,DR: This should be a host/deployer decision, not the Guest. There > may other guest OS, which do not do RIPAS_RAM early enough. > Are we suggesting that when the guest is running out of DRAM initialized via rmi_rtt_data_map_init(), it may need to access memory outside that range before it gets a chance to set the RIPAS as RAM? Does that mean the guest now has to trust the host for that? rmi_rtt_init_ripas() is not added to the measurement details, right? -aneesh