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=-20.6 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 85124C433F1 for ; Wed, 22 Jul 2020 16:45:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 61C532176B for ; Wed, 22 Jul 2020 16:45:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="mvQ2D74Q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731338AbgGVQpR (ORCPT ); Wed, 22 Jul 2020 12:45:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731204AbgGVQpN (ORCPT ); Wed, 22 Jul 2020 12:45:13 -0400 Received: from mail-wr1-x441.google.com (mail-wr1-x441.google.com [IPv6:2a00:1450:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1345C0619E0 for ; Wed, 22 Jul 2020 09:45:12 -0700 (PDT) Received: by mail-wr1-x441.google.com with SMTP id r12so2524651wrj.13 for ; Wed, 22 Jul 2020 09:45:12 -0700 (PDT) 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=bcTngC2Bes9sF1CupaxPgWX3tAw0UoRfYaGJIdlmeeQ=; b=mvQ2D74QyUwCzSPTgbT4sWDjrm7UJoVfL3cHenKVZM4lEyQ4kiJMrsWap47ViZ/Wvr rZDWLr9NFPdHynImP8k+kUbehz7sK/izWI9taaixH28DDyAQxLDE2IVjI4JHth6sqvMd Bm3MyxL4Ev2MPQ719BJsT1suvEsdnYD9LiwdooMdWfuceghQTEMxSuCUAzFCiQNkszgr 776DU9p9GQmi0hKDgGS6X4PrAU7F1kaKRpoHIctLA3l3w5RGa68JqwP9mYrDKItjiXEp YdYfHynQXX5o0Cs0P73flkaXSX7R5VWhnBQrZk7Ew+typZtMNI/jv6YpF1C6khkBO0C0 nNTw== 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=bcTngC2Bes9sF1CupaxPgWX3tAw0UoRfYaGJIdlmeeQ=; b=S6cAsl2iwMhqrGhBs5OzHPDImYfc15l0PJbJZ21ulQXDWnHd/t7AWW+UP5F5o4jSox s+YllJwa3LrrsGieGGJt1DWtxs88JcpZ1kdV5kv+wjePQWNjGuG445xHp+FPzJa2+nEK u6ckVmdZ5l/hTZD+uxBG3fY44U/bEZA+CKU8+ECbXsAG13aky9uWtsldXIjaopntgR/6 6MF5VOHUqz6EnpLlRBiveQqzl13exQyk2k3rHsEwyEmqQSuWPe6MojNemU+JYLLzg7LX bGo7cBSpugHbeW8p6hKtGAANd+0At70nnjRYvxMFZ9xVGpF4ae6lhu1pJZHxY69qPW7m 9BbA== X-Gm-Message-State: AOAM531qaf8/QoXpkT73VvSbLdDLCvq+jN4mxdPG0xUhFf92j3dQYPUG VqD/ZF8fsF6uZl8VOgxdblLxzQ== X-Google-Smtp-Source: ABdhPJx2hxeObfvv1sweoqi7kI9BIJM5pRi6WnEDs4mkAmQ3drosmvpJW+pWqVpWlbJoNaizyRi9hA== X-Received: by 2002:a5d:558a:: with SMTP id i10mr388087wrv.146.1595436311404; Wed, 22 Jul 2020 09:45:11 -0700 (PDT) Received: from localhost ([2a01:4b00:8523:2d03:b0ee:900a:e004:b9d0]) by smtp.gmail.com with ESMTPSA id e5sm631557wrc.37.2020.07.22.09.45.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 22 Jul 2020 09:45:10 -0700 (PDT) From: David Brazdil To: Catalin Marinas , Will Deacon , Marc Zyngier , Dennis Zhou , Tejun Heo , Christoph Lameter , Arnd Bergmann Cc: James Morse , Julien Thierry , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arch@vger.kernel.org, kernel-team@google.com, David Brazdil Subject: [PATCH 7/9] kvm: arm64: Mark hyp stack pages reserved Date: Wed, 22 Jul 2020 17:44:22 +0100 Message-Id: <20200722164424.42225-8-dbrazdil@google.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200722164424.42225-1-dbrazdil@google.com> References: <20200722164424.42225-1-dbrazdil@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In preparation for unmapping hyp pages from host stage-2, allocate/free hyp stack using new helpers which automatically mark the pages reserved. Signed-off-by: David Brazdil --- arch/arm64/kvm/arm.c | 49 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 47 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 0700c3d21b23..dc557b380c87 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1451,13 +1451,58 @@ static int init_subsystems(void) return err; } +/* + * Alloc pages and mark them reserved so the kernel never tries to + * take them away from the hypervisor. + */ +static unsigned long alloc_hyp_pages(gfp_t flags, unsigned int order) +{ + struct page *page; + unsigned long i; + + page = alloc_pages(flags, order); + if (!page) + return 0; + + for (i = 0; i < (1ul << order); ++i) + mark_page_reserved(page + i); + + return (unsigned long)page_address(page); +} + +static unsigned long alloc_hyp_page(gfp_t flags) +{ + return alloc_hyp_pages(flags, 0); +} + +/* + * Free pages which were previously marked reserved for the hypervisor. + */ +static void free_hyp_pages(unsigned long addr, unsigned int order) +{ + unsigned long i; + struct page *page; + + if (!addr) + return; + + page = virt_to_page(addr); + for (i = 0; i < (1ul << order); ++i) + free_reserved_page(page + i); +} + +static void free_hyp_page(unsigned long addr) +{ + return free_hyp_pages(addr, 0); +} + static void teardown_hyp_mode(void) { int cpu; free_hyp_pgds(); for_each_possible_cpu(cpu) - free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); + free_hyp_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); } /** @@ -1481,7 +1526,7 @@ static int init_hyp_mode(void) for_each_possible_cpu(cpu) { unsigned long stack_page; - stack_page = __get_free_page(GFP_KERNEL); + stack_page = alloc_hyp_page(GFP_KERNEL); if (!stack_page) { err = -ENOMEM; goto out_err; -- 2.27.0