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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1BE2AC433EF for ; Tue, 5 Oct 2021 11:37:47 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id BCC97614C8 for ; Tue, 5 Oct 2021 11:37:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org BCC97614C8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 5EECE4B2D7; Tue, 5 Oct 2021 07:37:46 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ZtBXK0XUspox; Tue, 5 Oct 2021 07:37:45 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 2A9A24B2D1; Tue, 5 Oct 2021 07:37:45 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A19064B2E0 for ; Tue, 5 Oct 2021 07:37:43 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Hn7DPYWa4KDr for ; Tue, 5 Oct 2021 07:37:41 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id ADB7B4B2C5 for ; Tue, 5 Oct 2021 07:37:40 -0400 (EDT) Received: by mail.kernel.org (Postfix) with ESMTPSA id 54145613B5; Tue, 5 Oct 2021 11:37:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1633433859; bh=ZWaJJwHIoiSMX2b1TzjXDuohjgGWYlfHhl5VaPUzhPE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tdQCKHC3yP/qRKu9bnejn4UBDc1tArx5Z2hwQvhWiba1Hb/mX7DcTy5wj8ts1CxdR IET6zBQSPlJwtLaVfA11YeTzf034VsZBfC0tiVO9f8NSGIdAJWaHNYOPB615zNtQ62 WnAQCxXV09yJALKSEjbgt6a0CNCmRPOoCk997KkublwH5asFu+pKxLQzCSVIEEvoRK qW78wkNtQQJuZlKyDqUEFz5yx1d80j7JnMwFUVZskbBBngpgkcDYMSekpTqXgn4s8e d064B0dB+aCe3dVwc8FzMJ5wFrOhDL3JQfUk9EY0lB9j7c09u9lry5xzV4eQcDyJxm rZKZAXcdSM+sg== From: Will Deacon To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 2/5] KVM: arm64: Reject stub hypercalls after pKVM has been initialised Date: Tue, 5 Oct 2021 12:37:18 +0100 Message-Id: <20211005113721.29441-3-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20211005113721.29441-1-will@kernel.org> References: <20211005113721.29441-1-will@kernel.org> MIME-Version: 1.0 Cc: Marc Zyngier , Catalin Marinas , Will Deacon , kvmarm@lists.cs.columbia.edu X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu The stub hypercalls provide mechanisms to reset and replace the EL2 code, so uninstall them once pKVM has been initialised in order to ensure the integrity of the hypervisor code. To ensure pKVM initialisation remains functional, split cpu_hyp_reinit() into two helper functions to separate usage of the stub from usage of pkvm hypercalls either side of __pkvm_init on the boot CPU. Cc: Marc Zyngier Reviewed-by: Quentin Perret Signed-off-by: Will Deacon --- arch/arm64/kvm/arm.c | 31 +++++++++++++++++++++++-------- arch/arm64/kvm/hyp/nvhe/host.S | 26 +++++++++++++++++--------- 2 files changed, 40 insertions(+), 17 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index fe102cd2e518..9506cf88fa0e 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1579,25 +1579,33 @@ static void cpu_set_hyp_vector(void) kvm_call_hyp_nvhe(__pkvm_cpu_set_vector, data->slot); } -static void cpu_hyp_reinit(void) +static void cpu_hyp_init_context(void) { kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); - cpu_hyp_reset(); - - if (is_kernel_in_hyp_mode()) - kvm_timer_init_vhe(); - else + if (!is_kernel_in_hyp_mode()) cpu_init_hyp_mode(); +} +static void cpu_hyp_init_features(void) +{ cpu_set_hyp_vector(); - kvm_arm_init_debug(); + if (is_kernel_in_hyp_mode()) + kvm_timer_init_vhe(); + if (vgic_present) kvm_vgic_init_cpu_hardware(); } +static void cpu_hyp_reinit(void) +{ + cpu_hyp_reset(); + cpu_hyp_init_context(); + cpu_hyp_init_features(); +} + static void _kvm_arch_hardware_enable(void *discard) { if (!__this_cpu_read(kvm_arm_hardware_enabled)) { @@ -1788,10 +1796,17 @@ static int do_pkvm_init(u32 hyp_va_bits) int ret; preempt_disable(); - hyp_install_host_vector(); + cpu_hyp_init_context(); ret = kvm_call_hyp_nvhe(__pkvm_init, hyp_mem_base, hyp_mem_size, num_possible_cpus(), kern_hyp_va(per_cpu_base), hyp_va_bits); + cpu_hyp_init_features(); + + /* + * The stub hypercalls are now disabled, so set our local flag to + * prevent a later re-init attempt in kvm_arch_hardware_enable(). + */ + __this_cpu_write(kvm_arm_hardware_enabled, 1); preempt_enable(); return ret; diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S index 4b652ffb591d..0c6116d34e18 100644 --- a/arch/arm64/kvm/hyp/nvhe/host.S +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -110,17 +110,14 @@ SYM_FUNC_START(__hyp_do_panic) b __host_enter_for_panic SYM_FUNC_END(__hyp_do_panic) -.macro host_el1_sync_vect - .align 7 -.L__vect_start\@: - stp x0, x1, [sp, #-16]! - mrs x0, esr_el2 - lsr x0, x0, #ESR_ELx_EC_SHIFT - cmp x0, #ESR_ELx_EC_HVC64 - b.ne __host_exit - +SYM_FUNC_START(__host_hvc) ldp x0, x1, [sp] // Don't fixup the stack yet + /* No stub for you, sonny Jim */ +alternative_if ARM64_KVM_PROTECTED_MODE + b __host_exit +alternative_else_nop_endif + /* Check for a stub HVC call */ cmp x0, #HVC_STUB_HCALL_NR b.hs __host_exit @@ -137,6 +134,17 @@ SYM_FUNC_END(__hyp_do_panic) ldr x5, =__kvm_handle_stub_hvc hyp_pa x5, x6 br x5 +SYM_FUNC_END(__host_hvc) + +.macro host_el1_sync_vect + .align 7 +.L__vect_start\@: + stp x0, x1, [sp, #-16]! + mrs x0, esr_el2 + lsr x0, x0, #ESR_ELx_EC_SHIFT + cmp x0, #ESR_ELx_EC_HVC64 + b.eq __host_hvc + b __host_exit .L__vect_end\@: .if ((.L__vect_end\@ - .L__vect_start\@) > 0x80) .error "host_el1_sync_vect larger than vector entry" -- 2.33.0.800.g4c38ced690-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm