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 X-Spam-Level: X-Spam-Status: No, score=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A278C64E7C for ; Wed, 2 Dec 2020 18:43:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFEC22224F for ; Wed, 2 Dec 2020 18:43:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389402AbgLBSnJ (ORCPT ); Wed, 2 Dec 2020 13:43:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389369AbgLBSnH (ORCPT ); Wed, 2 Dec 2020 13:43:07 -0500 Received: from mail-wm1-x341.google.com (mail-wm1-x341.google.com [IPv6:2a00:1450:4864:20::341]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E39CC08E860 for ; Wed, 2 Dec 2020 10:41:55 -0800 (PST) Received: by mail-wm1-x341.google.com with SMTP id h21so11165582wmb.2 for ; Wed, 02 Dec 2020 10:41:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=FbhNL96u68QqM7Q1rkLQfNYMQNpyFncRvPJJEVMReqU=; b=aFE7s/N+LJ2214UmKW0aNWOqdMUPnXoa+EPsqwgnoGGxb8gEhdDmTcErY0lO7VX/of Pl4LzHwCPIYUm5h24H+uF+GVjDF8jfobBT3gBZqMIo6DJhMVbKU7Tear3xnCtVJhTA5Z H8UdHSoYKkI3GbRtMA+e9t2FLeHRS1USlflwgf2iXaGNryzWx/cGxM/H1WIW7F0TzFQm kUYSeVPW0o7VN8rQmnKCZzuQhKnOlQdi0fKh13kN7DNpfC847bpT3mlXKhcpfipcvWLM zXmrrrlzQf8R9QP/5CcjD6TobUxbU4+VxaXnueeA5C4NZSfWnZQsKClVCGz391574KZb MG+A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=FbhNL96u68QqM7Q1rkLQfNYMQNpyFncRvPJJEVMReqU=; b=fG4om8gvot1wpMRzJfgMggW70WemEIYlxvUUB0HeSGaeEIGjnJZzWaqib/Q16QQrX8 Jx3kAj8yZR8hXfk3+OZinnmSZ1lCNRcERwbsfvcV8y3VKobGXu3jj682DVpR2FuxrlPU pg1cfHByeJ7cW7JyoEeRuuE/IfIRGSGpNMQNIwZ+pJIWkUd0KpjnIKzlIIMu+mlvymPi 2ZMVFPl6p1LKIi6QN/Rla17M5wRtu7C446oEJU3CkfnMKBXraANYG1p9sbRbtIq3lnVj j/LizqIYQHI3fLV1bXKUk22pRtkqq975DzYYDTZ7V1Y7NZsA6P/HD73rUcV6gxus9QaD RQlQ== X-Gm-Message-State: AOAM5319Owx0IYhlqzVqtqVhNSShHeyLs9PfO8x2Olt/+LzbLylMDdPp dMZEwaZVDsMOJz3/JMS7/6a4fA== X-Google-Smtp-Source: ABdhPJzDonMAoe1/LUSeGrzjO/oX6VvyeXOfTR80+KWmzVofsLNtAQuxbUf5v7Ho6BG2owrCpnDifw== X-Received: by 2002:a05:600c:2306:: with SMTP id 6mr4532227wmo.53.1606934514097; Wed, 02 Dec 2020 10:41:54 -0800 (PST) Received: from localhost ([2a01:4b00:8523:2d03:5ddd:b7c5:e3c9:e87a]) by smtp.gmail.com with ESMTPSA id z140sm573266wmc.30.2020.12.02.10.41.52 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 02 Dec 2020 10:41:52 -0800 (PST) From: David Brazdil To: kvmarm@lists.cs.columbia.edu Cc: Jonathan Corbet , Catalin Marinas , Will Deacon , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , Dennis Zhou , Tejun Heo , Christoph Lameter , Mark Rutland , Lorenzo Pieralisi , Sudeep Holla , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel-team@android.com, David Brazdil Subject: [PATCH v4 12/26] kvm: arm64: Add .hyp.data..ro_after_init ELF section Date: Wed, 2 Dec 2020 18:41:08 +0000 Message-Id: <20201202184122.26046-13-dbrazdil@google.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201202184122.26046-1-dbrazdil@google.com> References: <20201202184122.26046-1-dbrazdil@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Add rules for renaming the .data..ro_after_init ELF section in KVM nVHE object files to .hyp.data..ro_after_init, linking it into the kernel and mapping it in hyp at runtime. The section is RW to the host, then mapped RO in hyp. The expectation is that the host populates the variables in the section and they are never changed by hyp afterwards. Signed-off-by: David Brazdil --- arch/arm64/include/asm/sections.h | 1 + arch/arm64/kernel/vmlinux.lds.S | 10 ++++++++++ arch/arm64/kvm/arm.c | 8 ++++++++ arch/arm64/kvm/hyp/nvhe/hyp.lds.S | 1 + 4 files changed, 20 insertions(+) diff --git a/arch/arm64/include/asm/sections.h b/arch/arm64/include/asm/sections.h index 3994169985ef..8ff579361731 100644 --- a/arch/arm64/include/asm/sections.h +++ b/arch/arm64/include/asm/sections.h @@ -11,6 +11,7 @@ extern char __alt_instructions[], __alt_instructions_end[]; extern char __hibernate_exit_text_start[], __hibernate_exit_text_end[]; extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[]; extern char __hyp_text_start[], __hyp_text_end[]; +extern char __hyp_data_ro_after_init_start[], __hyp_data_ro_after_init_end[]; extern char __idmap_text_start[], __idmap_text_end[]; extern char __initdata_begin[], __initdata_end[]; extern char __inittext_begin[], __inittext_end[]; diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index 1bda604f4c70..4382b5d0645d 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -30,6 +30,13 @@ jiffies = jiffies_64; *(__kvm_ex_table) \ __stop___kvm_ex_table = .; +#define HYPERVISOR_DATA_SECTIONS \ + HYP_SECTION_NAME(.data..ro_after_init) : { \ + __hyp_data_ro_after_init_start = .; \ + *(HYP_SECTION_NAME(.data..ro_after_init)) \ + __hyp_data_ro_after_init_end = .; \ + } + #define HYPERVISOR_PERCPU_SECTION \ . = ALIGN(PAGE_SIZE); \ HYP_SECTION_NAME(.data..percpu) : { \ @@ -37,6 +44,7 @@ jiffies = jiffies_64; } #else /* CONFIG_KVM */ #define HYPERVISOR_EXTABLE +#define HYPERVISOR_DATA_SECTIONS #define HYPERVISOR_PERCPU_SECTION #endif @@ -234,6 +242,8 @@ SECTIONS _sdata = .; RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_ALIGN) + HYPERVISOR_DATA_SECTIONS + /* * Data written with the MMU off but read with the MMU on requires * cache lines to be invalidated, discarding up to a Cache Writeback diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 6c8594378865..40857cbed3d1 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1705,6 +1705,14 @@ static int init_hyp_mode(void) goto out_err; } + err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_ro_after_init_start), + kvm_ksym_ref(__hyp_data_ro_after_init_end), + PAGE_HYP_RO); + if (err) { + kvm_err("Cannot map .hyp.data..ro_after_init section\n"); + goto out_err; + } + err = create_hyp_mappings(kvm_ksym_ref(__start_rodata), kvm_ksym_ref(__end_rodata), PAGE_HYP_RO); if (err) { diff --git a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S index bb2d986ff696..5d76ff2ba63e 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S +++ b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S @@ -16,4 +16,5 @@ SECTIONS { HYP_SECTION_NAME(.data..percpu) : { PERCPU_INPUT(L1_CACHE_BYTES) } + HYP_SECTION(.data..ro_after_init) } -- 2.29.2.454.gaff20da3a2-goog