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=-20.4 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=ham 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 841FEC43461 for ; Wed, 16 Sep 2020 20:00:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 18CA720936 for ; Wed, 16 Sep 2020 20:00:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="HNZo35gC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728130AbgIPUAf (ORCPT ); Wed, 16 Sep 2020 16:00:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726530AbgIPRfW (ORCPT ); Wed, 16 Sep 2020 13:35:22 -0400 Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F205C061223 for ; Wed, 16 Sep 2020 10:35:04 -0700 (PDT) Received: by mail-wm1-x343.google.com with SMTP id z9so3903767wmk.1 for ; Wed, 16 Sep 2020 10:35:04 -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=3ZouLpoLHZGhnRn3IE3lAdYTtqQtOaDPWcW0BXT72MM=; b=HNZo35gC+J7olQM/J4RAmLlZS6QxVf8SG/2BDEI9P1bohZ+P5Q96wTZVwc7II0n9BL cgE7q3s2HuB8SyeYAwP76jfvS9ilgnaSdWf3BN5CpaP3PpCWpHo7OyCzXoLczzUjYIh+ TAvf72HVFbYYjUfwXRs9KQWyCZzjv5SmQjRTwHXgeAoUK3/2zXTwbrvIkPx4Um1P5RvS TU1N+Ppw0DKArVS8ynQ4bf+jV171VTr1y4ZU53me1jkwW1cniiMaCioHU1u/AMChZdp6 1BnnWaIQvyESEBhMsuSyugrLCEkTdp5crIYFCA9FneqGow+l1YuEeHkCEHhBbzEX3vON E0iQ== 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=3ZouLpoLHZGhnRn3IE3lAdYTtqQtOaDPWcW0BXT72MM=; b=j1arjmfs5qkpR0qD0bNuxBbPXx7FQe6x5U8G7G8vdr57V4rj76nLQb1Og77nDZPOw7 RZy+TC9DW/f0J1eshIdgkC2rsmSkY+lAEBvoYfchLbo3gRnXpCHRCrVLQvL3hwiDU+BL 8z4+GyJabitJXlFKXq/ETy6SNWYTawmeRCsyDn0Sn2T51ry1OLWYVDyvbqaB9eM9e3no Sbut1S4c1iO2DLFA/CARx/1E2Gkxi//VXYkFE/9/tJ16wxOiZw04LSlAAJ8JaYf+6Ig9 +qyTnqieCkdGgTyHeFN543QtVKLzf0IXUsqcdVRrLZUbgwab72ruA43sg/kR1U7PzMc6 WbTg== X-Gm-Message-State: AOAM530Q1GV6L7XXbZwTb7nS72jAMgKalujLEa7JQZmZ1OUIGLY4/z+P 51QCG1tYlppHjZTHFuRW1KMsKg== X-Google-Smtp-Source: ABdhPJyjAeHVuIWwfCgiltujOqCdZJciMMvPMbdeAr38UjlrUERhWuN+mDjxXhXo26gYVThTzJRNbg== X-Received: by 2002:a1c:2e08:: with SMTP id u8mr6233481wmu.156.1600277702955; Wed, 16 Sep 2020 10:35:02 -0700 (PDT) Received: from localhost ([2a01:4b00:8523:2d03:e49d:f6be:d31b:ad3c]) by smtp.gmail.com with ESMTPSA id p1sm8808360wma.0.2020.09.16.10.35.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 16 Sep 2020 10:35:01 -0700 (PDT) From: David Brazdil To: kvmarm@lists.cs.columbia.edu Cc: Catalin Marinas , Will Deacon , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , Dennis Zhou , Tejun Heo , Christoph Lameter , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel-team@android.com, David Brazdil Subject: [PATCH v3 09/11] kvm: arm64: Mark hyp stack pages reserved Date: Wed, 16 Sep 2020 18:34:37 +0100 Message-Id: <20200916173439.32265-10-dbrazdil@google.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200916173439.32265-1-dbrazdil@google.com> References: <20200916173439.32265-1-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 7af9809fa193..58d7d614519b 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1456,13 +1456,58 @@ 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)); } /** @@ -1486,7 +1531,7 @@ 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; -- 2.28.0.618.gf4bc123cb7-goog