From patchwork Mon Oct 17 11:52:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 13008714 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 4AC5EC4332F for ; Mon, 17 Oct 2022 12:05:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZKtnfBFbEtD/AaSmhDvU3sm2FygB6hlI9yv0NJqdyCo=; b=fq7KuWh+2lEPVc 7baowTr5RK9JNc/ufH+Jmn+uEU6v8BZy2Uh8byPjdMKdlipMTrDaF8nI9GfDm8fifU8hKKzEAfJPG XPC5KONQCnmeRuOSvGY8t17KKo+N3MZkHCr8qL0+w7hCUsiCa4pXXUuXIgUS+qP4f/mAxyL9EMRVa Ci+SsbDeLKtCwC4uaNkG65TfxEzFTgze+gaax+t++QegYu8GQI6dCDprHnAoVuRTPKVAWLd17hxMv JFIhcZNlKHhixfJsToXFBuQy2W4LDUTZLgDc6mfQnnQZFK04a+xQWGJIQwDx1l7Zkf6dVYewzuFJk d9VlzwpNUfZZv4EQVpVQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1okOr2-00BM3B-TJ; Mon, 17 Oct 2022 12:04:25 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1okOgg-00BDSs-N8 for linux-arm-kernel@lists.infradead.org; Mon, 17 Oct 2022 11:53:44 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 5154DB81632; Mon, 17 Oct 2022 11:53:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 194EEC433B5; Mon, 17 Oct 2022 11:53:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1666007620; bh=JkBWkPIuSIXe9eQIz3zlM+OZss3C50u/x/WKjBuAZA4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hJY/44EbJqi2edZBxPtRVP+qqaSOASnhmgTqtaEnSFfMaRQR3Xjt4JML3efHQEhEo ZaA0q0tC5hwUQF3g4+nzF0tAVFQSZqWj/d0lkXr2GcR7W1hh6udqBXQ+S8qdBUyOuM hpjGLuFdAs4iKaYd4IjPFmfrr68J/vTxZ7MsNVQOlavnPKna8LzfwltrPvImuE0cG/ LIPof/259t6jrlLRUKYvx4+VHbK2tAF7TPIQb8gKkHJw44HgNfZEwmZEF2XFuCTGe2 4aXy6IWT7OgqutZA82DWSk3r0+MeksIsGjIXCGckqMyRVc5jCdeJY3pwvO90gm5gxD CsLQaVas1j/yg== From: Will Deacon To: kvmarm@lists.linux.dev Cc: Will Deacon , Sean Christopherson , Vincent Donnefort , Alexandru Elisei , Catalin Marinas , James Morse , Chao Peng , Quentin Perret , Suzuki K Poulose , Mark Rutland , Fuad Tabba , Oliver Upton , Marc Zyngier , kernel-team@android.com, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 22/25] KVM: arm64: Maintain a copy of 'kvm_arm_vmid_bits' at EL2 Date: Mon, 17 Oct 2022 12:52:06 +0100 Message-Id: <20221017115209.2099-23-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20221017115209.2099-1-will@kernel.org> References: <20221017115209.2099-1-will@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221017_045343_076275_27BEF63B X-CRM114-Status: GOOD ( 17.24 ) 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 Sharing 'kvm_arm_vmid_bits' between EL1 and EL2 allows the host to modify the variable arbitrarily, potentially leading to all sorts of shenanians as this is used to configure the VTTBR register for the guest stage-2. In preparation for unmapping host sections entirely from EL2, maintain a copy of 'kvm_arm_vmid_bits' in the pKVM hypervisor and initialise it from the host value while it is still trusted. Tested-by: Vincent Donnefort Signed-off-by: Will Deacon --- arch/arm64/include/asm/kvm_hyp.h | 2 ++ arch/arm64/kernel/image-vars.h | 3 --- arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/hyp/nvhe/pkvm.c | 3 +++ 4 files changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index fd99cf09972d..6797eafe7890 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -124,4 +124,6 @@ extern u64 kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val); extern u64 kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val); extern unsigned long kvm_nvhe_sym(__icache_flags); +extern unsigned int kvm_nvhe_sym(kvm_arm_vmid_bits); + #endif /* __ARM64_KVM_HYP_H__ */ diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index ae8f37f4aa8c..31ad75da4d58 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -71,9 +71,6 @@ KVM_NVHE_ALIAS(nvhe_hyp_panic_handler); /* Vectors installed by hyp-init on reset HVC. */ KVM_NVHE_ALIAS(__hyp_stub_vectors); -/* VMID bits set by the KVM VMID allocator */ -KVM_NVHE_ALIAS(kvm_arm_vmid_bits); - /* Static keys which are set if a vGIC trap should be handled in hyp. */ KVM_NVHE_ALIAS(vgic_v2_cpuif_trap); KVM_NVHE_ALIAS(vgic_v3_cpuif_trap); diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 25467f24803d..1d4b8122d010 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1893,6 +1893,7 @@ static void kvm_hyp_init_symbols(void) kvm_nvhe_sym(id_aa64mmfr1_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); kvm_nvhe_sym(id_aa64mmfr2_el1_sys_val) = read_sanitised_ftr_reg(SYS_ID_AA64MMFR2_EL1); kvm_nvhe_sym(__icache_flags) = __icache_flags; + kvm_nvhe_sym(kvm_arm_vmid_bits) = kvm_arm_vmid_bits; } static int kvm_hyp_init_protection(u32 hyp_va_bits) diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c index f5f300cc5864..826335ccad9d 100644 --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -15,6 +15,9 @@ /* Used by icache_is_vpipt(). */ unsigned long __icache_flags; +/* Used by kvm_get_vttbr(). */ +unsigned int kvm_arm_vmid_bits; + /* * Set trap register values based on features in ID_AA64PFR0. */