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 48AD8C433EF for ; Mon, 23 May 2022 19:35:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229647AbiEWTfV (ORCPT ); Mon, 23 May 2022 15:35:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231577AbiEWTfA (ORCPT ); Mon, 23 May 2022 15:35:00 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC6CD72210 for ; Mon, 23 May 2022 12:21:37 -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 C88E361309 for ; Mon, 23 May 2022 19:21:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0A68C385AA; Mon, 23 May 2022 19:21:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1653333696; bh=VDByln83gsysqnSJxc/OKcvr4RM63ItlgGR+QfBwo6A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YwRdkwzZJY6rLulqo3CnP/Eebai2Edpk/++7CruSoGaThlOIFUCtifd05SI15O7NE 4W9MDZRhe6akviSfJQlN1eWTiBKEIe58xGfWfEXIvZHWGNso6SE3771oqNih6zkA9u zcq1q3opmE+pCDTtQ0c0YY93zwL6NFvRq0HklcFKtn6YP33rCZqOuJnJY6gOTn75rq oHUDvh6pBAtdlLHoyu2Mebg4pjxUoGbkDU7ELA08S/JLcJ76kQyh0ywcXvY6XPAdD4 XNUL44fBwxzHn/CxnImqAIv8jfjQtwWkYOWIEVvh6VJV8iZxsa3lizZ7N29mtSQbZz 5EM+dRws6dAUg== Date: Mon, 23 May 2022 22:19:54 +0300 From: Jarkko Sakkinen To: "Zhang, Cathy" Cc: "Li, Zhiquan1" , "linux-sgx@vger.kernel.org" , "x86@kernel.org" , "Chatre, Reinette" , "Hansen, Dave" , "Raj, Ashok" , "chao.p.peng@linux.intel.com" , "Zhong, Yang" Subject: Re: [PATCH v5 3/9] x86/sgx: Keep record for SGX VA and Guest page type Message-ID: References: <20220520103904.1216-1-cathy.zhang@intel.com> <20220520103904.1216-4-cathy.zhang@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Mon, May 23, 2022 at 06:09:55AM +0000, Zhang, Cathy wrote: > Hi Jarkko, > > > -----Original Message----- > > From: Zhang, Cathy > > Sent: Monday, May 23, 2022 8:07 AM > > To: 'Jarkko Sakkinen' ; Li, Zhiquan1 > > > > Cc: linux-sgx@vger.kernel.org; x86@kernel.org; Chatre, Reinette > > ; Hansen, Dave ; Raj, > > Ashok ; chao.p.peng@linux.intel.com; Zhong, Yang > > > > Subject: RE: [PATCH v5 3/9] x86/sgx: Keep record for SGX VA and Guest page > > type > > > > Hi Jarkko, > > > > > -----Original Message----- > > > From: Jarkko Sakkinen > > > Sent: Saturday, May 21, 2022 3:11 AM > > > To: Zhang, Cathy ; Li, Zhiquan1 > > > > > > Cc: linux-sgx@vger.kernel.org; x86@kernel.org; Chatre, Reinette > > > ; Hansen, Dave ; > > > Raj, Ashok ; chao.p.peng@linux.intel.com; Zhong, > > > Yang > > > Subject: Re: [PATCH v5 3/9] x86/sgx: Keep record for SGX VA and Guest > > > page type > > > > > > On Fri, May 20, 2022 at 06:38:58PM +0800, Cathy Zhang wrote: > > > > Regular enclave EPC pages have sgx_encl_page as their owner, but SGX > > > > VA page and KVM guest EPC page are maintained by different owner > > > > structures. > > > > > > > > SGX CPUSVN update requires to know the EPC page owner's status and > > > > then decide how to handle the page. > > > > > > > > Keep a record of page type for SGX VA and KVM guest page while the > > > > other EPC pages already have their type tracked, so that CPUSVN > > > > update can get EPC page's owner by type and handle it then. > > > > > > > > Signed-off-by: Cathy Zhang > > > > > > > > --- > > > > Changes since v3: > > > > - Rename SGX_EPC_PAGE_GUEST as SGX_EPC_PAGE_KVM_GUEST. > > > (Suggested by > > > > Jarkko, Sakkinen) > > > > --- > > > > arch/x86/kernel/cpu/sgx/sgx.h | 4 ++++ > > > > arch/x86/kernel/cpu/sgx/encl.c | 2 ++ > > > > arch/x86/kernel/cpu/sgx/virt.c > > > > | 2 ++ > > > > 3 files changed, 8 insertions(+) > > > > > > > > diff --git a/arch/x86/kernel/cpu/sgx/sgx.h > > > > b/arch/x86/kernel/cpu/sgx/sgx.h index f8ed9deac18b..4ad0e5396eef > > > > 100644 > > > > --- a/arch/x86/kernel/cpu/sgx/sgx.h > > > > +++ b/arch/x86/kernel/cpu/sgx/sgx.h > > > > @@ -28,6 +28,10 @@ > > > > > > > > /* Pages on free list */ > > > > #define SGX_EPC_PAGE_IS_FREE BIT(1) > > > > +/* VA page */ > > > > +#define SGX_EPC_PAGE_VA BIT(2) > > > > +/* Pages allocated for KVM guest */ > > > > +#define SGX_EPC_PAGE_KVM_GUEST BIT(3) > > > > > > > > struct sgx_epc_page { > > > > unsigned int section; > > > > diff --git a/arch/x86/kernel/cpu/sgx/encl.c > > > > b/arch/x86/kernel/cpu/sgx/encl.c index 08f39fa03a39..383abd538ac9 > > > > 100644 > > > > --- a/arch/x86/kernel/cpu/sgx/encl.c > > > > +++ b/arch/x86/kernel/cpu/sgx/encl.c > > > > @@ -912,6 +912,8 @@ struct sgx_epc_page *sgx_alloc_va_page(struct > > > sgx_va_page *va_page) > > > > return ERR_PTR(-EFAULT); > > > > } > > > > > > > > + epc_page->flags |= SGX_EPC_PAGE_VA; > > > > + > > > > return epc_page; > > > > } > > > > > > > > diff --git a/arch/x86/kernel/cpu/sgx/virt.c > > > > b/arch/x86/kernel/cpu/sgx/virt.c index e953816d7c8b..104487b72fb8 > > > > 100644 > > > > --- a/arch/x86/kernel/cpu/sgx/virt.c > > > > +++ b/arch/x86/kernel/cpu/sgx/virt.c > > > > @@ -50,6 +50,8 @@ static int __sgx_vepc_fault(struct sgx_vepc *vepc, > > > > if (IS_ERR(epc_page)) > > > > return PTR_ERR(epc_page); > > > > > > > > + epc_page->flags |= SGX_EPC_PAGE_KVM_GUEST; > > > > > > This would need to be synced up with SGX_EPC_IS_VEPC: > > > > > > https://lore.kernel.org/linux-sgx/694234d7-6a0d-e85f-f2f9- > > > e52b4a61e1ec@intel.com/T/#t > > > > > > Otherwise, we have a chaos. > > > > > > Can you sync up with Zhiquan Li and find some common approach. IMHO, > > > it might even sense to merge these patch sets into one. Then it would > > > be easier to review them as a whole. > > > > Thanks for showing the above related patches, Jarkko! I just take a quick look > > at that series, AFAIK, __sgx_vepc_fault() will only be called during VM boot > > up to allocate physical EPC pages. > > Then, host does not know how VM works with those pages. VM SGX driver > > will handle any errors itself. > > So with the approach in that series, what it actually tracks is the vaddr in > > QEMU address space for all EPC pages allocated to the VM. Does host need > > to track such information? QEMU side should provide it easily I think. @Li, > > Zhiquan1. > > > > I've synced with Zhiquan Li and got the whole picture of his patch logic. I suggest > to follow the way how we handle the same change between EDMM and Seamless, > that is Zhiquan Li will apply patch 3 from Seamless and then add his left patches. > Please let's know if you have other suggestion. Thanks! Sounds reasonable! BR, Jarkko