From patchwork Wed Jan 13 23:35:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 12018235 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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 4AE05C43381 for ; Thu, 14 Jan 2021 01:57:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 09B662343B for ; Thu, 14 Jan 2021 01:57:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727844AbhANB5O (ORCPT ); Wed, 13 Jan 2021 20:57:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:54436 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729556AbhAMXpH (ORCPT ); Wed, 13 Jan 2021 18:45:07 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 658A823436; Wed, 13 Jan 2021 23:35:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1610580958; bh=+Og6SFQ5dtRv3KX4nqAmeOuIVYSsPIv667fYOcM5q7s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YC5nvPlffPZmwHsYsLSG+L5CglojaJQ9LFKSSIu+HMh6lkkM7oLsLK2+69uRR3+eK RluNf+awr+jOmyHg20M9rqqm9beIAQeR7QOdpU6th2E04WMGUfwExTxMil84iqi68I uerQG598QvVnfyBgfNxyuF7hHyfNvTnDkKDh7d/fK79wvPDrusZWND7lOUtwEEK9kK CuiGDMdo2KSjG/9n9ZhblbiCq+BLW4N0llb4dGxit6QFlrLkTPbgJ2vQRAiblwN3ob EobGG6dYPB8wksRI0gXSe2OVliv7vB6J9wiyXlA1fbiAKiZjFLzYftYjHS+tSJFvkY v5cSAbq0fUlEQ== From: jarkko@kernel.org To: linux-sgx@vger.kernel.org Cc: dave.hansen@intel.com, kai.huang@intel.com, haitao.huang@intel.com, seanjc@google.com, "jarkko@kernel.org" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" Subject: [PATCH v4 2/2] x86/sgx: Wipe out EREMOVE from sgx_free_epc_page() Date: Thu, 14 Jan 2021 01:35:41 +0200 Message-Id: <20210113233541.17669-3-jarkko@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210113233541.17669-1-jarkko@kernel.org> References: <20210113233541.17669-1-jarkko@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org From: "jarkko@kernel.org" Encapsulate the snippet in sgx_free_epc_page() concerning EREMOVE to sgx_reset_epc_page(), which is a static helper function for sgx_encl_release(). It's the only function existing, which deals with initialized pages. Signed-off-by: jarkko@kernel.org --- v3: Fixed va_page desctruction. v2: Fixed a compilation error s/page/epc_page/ change not amended to the patches. arch/x86/kernel/cpu/sgx/encl.c | 13 +++++++++++++ arch/x86/kernel/cpu/sgx/main.c | 10 ++++------ 2 files changed, 17 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c index ee50a5010277..a78b71447771 100644 --- a/arch/x86/kernel/cpu/sgx/encl.c +++ b/arch/x86/kernel/cpu/sgx/encl.c @@ -389,6 +389,16 @@ const struct vm_operations_struct sgx_vm_ops = { .access = sgx_vma_access, }; + +static void sgx_reset_epc_page(struct sgx_epc_page *epc_page) +{ + int ret; + + ret = __eremove(sgx_get_epc_virt_addr(epc_page)); + if (WARN_ONCE(ret, "EREMOVE returned %d (0x%x)", ret, ret)) + return; +} + /** * sgx_encl_release - Destroy an enclave instance * @kref: address of a kref inside &sgx_encl @@ -412,6 +422,7 @@ void sgx_encl_release(struct kref *ref) if (sgx_unmark_page_reclaimable(entry->epc_page)) continue; + sgx_reset_epc_page(entry->epc_page); sgx_free_epc_page(entry->epc_page); encl->secs_child_cnt--; entry->epc_page = NULL; @@ -423,6 +434,7 @@ void sgx_encl_release(struct kref *ref) xa_destroy(&encl->page_array); if (!encl->secs_child_cnt && encl->secs.epc_page) { + sgx_reset_epc_page(encl->secs.epc_page); sgx_free_epc_page(encl->secs.epc_page); encl->secs.epc_page = NULL; } @@ -431,6 +443,7 @@ void sgx_encl_release(struct kref *ref) va_page = list_first_entry(&encl->va_pages, struct sgx_va_page, list); list_del(&va_page->list); + sgx_reset_epc_page(va_page->epc_page); sgx_free_epc_page(va_page->epc_page); kfree(va_page); } diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index ebbd3b97b3d0..5e20b42f2639 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -598,16 +598,14 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim) * sgx_free_epc_page() - Free an EPC page * @page: an EPC page * - * Call EREMOVE for an EPC page and insert it back to the list of free pages. + * Put the EPC page back to the list of free pages. It's the callers + * responsibility to make sure that the page is in uninitialized state In other + * words, do EREMOVE, EWB or whatever operation is necessary before calling + * this function. */ void sgx_free_epc_page(struct sgx_epc_page *page) { struct sgx_epc_section *section = &sgx_epc_sections[page->section]; - int ret; - - ret = __eremove(sgx_get_epc_virt_addr(page)); - if (WARN_ONCE(ret, "EREMOVE returned %d (0x%x)", ret, ret)) - return; spin_lock(§ion->lock); list_add_tail(&page->list, §ion->page_list);