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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4B74C433EF for ; Thu, 21 Apr 2022 16:05:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1390475AbiDUQI0 (ORCPT ); Thu, 21 Apr 2022 12:08:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59384 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1390469AbiDUQIV (ORCPT ); Thu, 21 Apr 2022 12:08:21 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5BF7B1208C for ; Thu, 21 Apr 2022 09:05:30 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id EC02161C28 for ; Thu, 21 Apr 2022 16:05:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCC51C385A8; Thu, 21 Apr 2022 16:05:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1650557129; bh=D7er7Gkjv/f4i1Yu0ZUVinpq3kpPcMDuLA+oEQdw4ds=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RYi9fmMOeIx9QgGwYVfvMBfc2k4PeLKOPpWVpgFcBhAYCVtIES8+yiKfu4+uQ7rjx UB5OBzHiW7mb7o6gfwFvRk6l2mudmmV0zLAzGr9UMWfs4B2RH4QHqLOQ7dIpm8R7BT YdyxHrF1T6al93a+spFowtOS/BIEl0JASQX5xxQCkjgzorhmVNCMAqHDblF4iTdGna 033EMDzj538eCeAFeaohpnraeoNDsIYLfLiXmRWBzcEB3xOrWXHPaG/kASVW7wF+8N KIm2JNsjFLauWPQ4/fxVn7Vq3+2qTqt02U+qrQCxUTZRpqwYQDgdjcO1YQupb7CmgC JZm+UzOYiXW7A== Date: Thu, 21 Apr 2022 19:04:14 +0300 From: Jarkko Sakkinen To: Cathy Zhang Cc: linux-sgx@vger.kernel.org, x86@kernel.org, reinette.chatre@intel.com, dave.hansen@intel.com, ashok.raj@intel.com, chao.p.peng@intel.com, yang.zhong@intel.com Subject: Re: [PATCH v4 2/9] x86/sgx: Save enclave pointer for VA page Message-ID: References: <20220421110326.856-1-cathy.zhang@intel.com> <20220421110326.856-3-cathy.zhang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220421110326.856-3-cathy.zhang@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Thu, Apr 21, 2022 at 07:03:19PM +0800, Cathy Zhang wrote: > Tearing down all enclaves is required by SGX SVN update, which > involves running the ENCLS[EREMOVE] instruction on every EPC > page. This (tearing down all enclaves) should be coordinated > with any enclaves that may be in the process of existing and thus > already be running ENCLS[EREMOVE] as part of enclave release. > > In support of this coordination, it is required to know which enclave > owns each in-use EPC page. It is already possible to locate the > owning enclave of SECS and regular pages but not for VA pages. > > Make the following changes for VA pages' location: > 1) Make epc->owner type-agnostic by changing its type to 'void *'. So, > besides "struct sgx_encl_page", it can have other types, like > "struct sgx_va_page". > 2) Save the enclave pointer for each VA page to support locating its > owning enclave. > > Note: to track 2T EPC memory, this scheme of tracking will use > additional 8M memory. > > Signed-off-by: Cathy Zhang > > --- > Changes since v3: > - Squash patch "x86/sgx: Provide VA page non-NULL owner" and > "x86/sgx: Save enclave pointer for VA page". Update commit log. > (Suggested by Jarkko Sakkinen) > --- > arch/x86/kernel/cpu/sgx/encl.h | 4 ++-- > arch/x86/kernel/cpu/sgx/sgx.h | 2 +- > arch/x86/kernel/cpu/sgx/encl.c | 5 +++-- > arch/x86/kernel/cpu/sgx/ioctl.c | 3 ++- > 4 files changed, 8 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h > index 7cdc351bc273..59fbd4ed5c64 100644 > --- a/arch/x86/kernel/cpu/sgx/encl.h > +++ b/arch/x86/kernel/cpu/sgx/encl.h > @@ -76,6 +76,7 @@ struct sgx_va_page { > struct sgx_epc_page *epc_page; > DECLARE_BITMAP(slots, SGX_VA_SLOT_COUNT); > struct list_head list; > + struct sgx_encl *encl; > }; > > struct sgx_backing { > @@ -112,8 +113,7 @@ int sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index, > void sgx_encl_put_backing(struct sgx_backing *backing, bool do_write); > int sgx_encl_test_and_clear_young(struct mm_struct *mm, > struct sgx_encl_page *page); > - This line removal is not related to the patch. > -struct sgx_epc_page *sgx_alloc_va_page(void); > +struct sgx_epc_page *sgx_alloc_va_page(struct sgx_va_page *va_page); > unsigned int sgx_alloc_va_slot(struct sgx_va_page *va_page); > void sgx_free_va_slot(struct sgx_va_page *va_page, unsigned int offset); > bool sgx_va_page_full(struct sgx_va_page *va_page); > diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h > index d7a1490d90bb..f8ed9deac18b 100644 > --- a/arch/x86/kernel/cpu/sgx/sgx.h > +++ b/arch/x86/kernel/cpu/sgx/sgx.h > @@ -33,7 +33,7 @@ struct sgx_epc_page { > unsigned int section; > u16 flags; > u16 poison; > - struct sgx_encl_page *owner; > + void *owner; > struct list_head list; > }; > > diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c > index 68c8d65a8dee..c0725111cc25 100644 > --- a/arch/x86/kernel/cpu/sgx/encl.c > +++ b/arch/x86/kernel/cpu/sgx/encl.c > @@ -753,6 +753,7 @@ int sgx_encl_test_and_clear_young(struct mm_struct *mm, > > /** > * sgx_alloc_va_page() - Allocate a Version Array (VA) page > + * @va_page: struct sgx_va_page connected to this VA page > * > * Allocate a free EPC page and convert it to a Version Array (VA) page. > * > @@ -760,12 +761,12 @@ int sgx_encl_test_and_clear_young(struct mm_struct *mm, > * a VA page, > * -errno otherwise > */ > -struct sgx_epc_page *sgx_alloc_va_page(void) > +struct sgx_epc_page *sgx_alloc_va_page(struct sgx_va_page *va_page) > { > struct sgx_epc_page *epc_page; > int ret; > > - epc_page = sgx_alloc_epc_page(NULL, true); > + epc_page = sgx_alloc_epc_page(va_page, true); > if (IS_ERR(epc_page)) > return ERR_CAST(epc_page); > > diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c > index a4df72f715d7..b77343eb2d49 100644 > --- a/arch/x86/kernel/cpu/sgx/ioctl.c > +++ b/arch/x86/kernel/cpu/sgx/ioctl.c > @@ -30,7 +30,8 @@ static struct sgx_va_page *sgx_encl_grow(struct sgx_encl *encl) > if (!va_page) > return ERR_PTR(-ENOMEM); > > - va_page->epc_page = sgx_alloc_va_page(); > + va_page->encl = encl; > + va_page->epc_page = sgx_alloc_va_page(va_page); > if (IS_ERR(va_page->epc_page)) { > err = ERR_CAST(va_page->epc_page); > kfree(va_page); > -- > 2.17.1 > BR, Jarkko