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 B2A21C433EF for ; Wed, 8 Jun 2022 06:01:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234055AbiFHGAy (ORCPT ); Wed, 8 Jun 2022 02:00:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51184 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244194AbiFHFy5 (ORCPT ); Wed, 8 Jun 2022 01:54:57 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7CE661FDEAC for ; Tue, 7 Jun 2022 20:54:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1654660478; x=1686196478; h=message-id:subject:from:to:cc:date:in-reply-to: references:mime-version:content-transfer-encoding; bh=ZdiXHZUJo38IOKboQjnmaGENfeeHeX1A4dYpCywnqZQ=; b=Os0C+zZPVcEAPWgWjmldl1LR1F9dIkzqVoVX5AajkqvppxAgDhjLeD+p dVRQ/xdZobsdK9/UERTLMsD7aOW5jQc+bsPBljgQYnTKGBDTY9wW6Np3i sJzSihY8r5TP4GMUt5zqNf7BblKjP6eILE/PLfyuYO0appRIy+TZ70AUI 9R0ks3wZmYD9ZQYzzSaoSjpAD2iM/nIaVyL+v/2q463veyFczOxHsYakk fLtpvv+FnUhdTfah7dMeDEV5S76kH6SGAK8WSLTYHBKbqATIiwmcGb8/t ROCAvWvR1D0ZQ9kQf7ceh9xYsi8WBZj8jBJgVbKyT5GevrwUYwKLRGdqc g==; X-IronPort-AV: E=McAfee;i="6400,9594,10371"; a="274317999" X-IronPort-AV: E=Sophos;i="5.91,285,1647327600"; d="scan'208";a="274317999" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jun 2022 20:54:38 -0700 X-IronPort-AV: E=Sophos;i="5.91,285,1647327600"; d="scan'208";a="584604217" Received: from pkakkine-mobl1.amr.corp.intel.com (HELO khuang2-desk.gar.corp.intel.com) ([10.212.24.149]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jun 2022 20:54:36 -0700 Message-ID: <7ff6d1d2f727f9453ff89dc68da45ffc77520fdd.camel@intel.com> Subject: Re: [PATCH v4 1/3] x86/sgx: Repurpose the owner field as the virtual address of virtual EPC page From: Kai Huang To: Zhiquan Li , linux-sgx@vger.kernel.org, tony.luck@intel.com, jarkko@kernel.org, dave.hansen@linux.intel.com Cc: seanjc@google.com, fan.du@intel.com, cathy.zhang@intel.com Date: Wed, 08 Jun 2022 15:54:34 +1200 In-Reply-To: <20220608032654.1764936-2-zhiquan1.li@intel.com> References: <20220608032654.1764936-1-zhiquan1.li@intel.com> <20220608032654.1764936-2-zhiquan1.li@intel.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.4 (3.42.4-2.fc35) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Wed, 2022-06-08 at 11:26 +0800, Zhiquan Li wrote: > When a page triggers a machine check, it only reports the > physical address of EPC page. But in order to inject #MC into > hypervisor, the virtual address is required. Then repurpose the > "owner" field as the virtual address of the virtual EPC page so that > arch_memory_failure() can easily retrieve it. > > Add a new EPC page flag - SGX_EPC_PAGE_KVM_GUEST to interpret the > meaning of the field. > > Signed-off-by: Zhiquan Li > --- > Changes since V3: > - Move the definition of EPC page flag SGX_EPC_PAGE_KVM_GUEST from > Cathy's third patch of SGX rebootless recovery patch set but discard > irrelevant portion, since it might need more time to re-forge and > these are two different features. > Link: https://lore.kernel.org/linux-sgx/41704e5d4c03b49fcda12e695595211d950cfb08.camel@kernel.org/T/#m9782d23496cacecb7da07a67daa79f4b322ae170 > > Changes since V2: > - Rework the patch suggested by Jarkko. > - Remove struct sgx_vepc_page and relevant code. > - Remove new EPC page flag SGX_EPC_PAGE_IS_VEPC definition as it is > duplicated to SGX_EPC_PAGE_KVM_GUEST. > Link: https://lore.kernel.org/linux-sgx/eb95b32ecf3d44a695610cf7f2816785@intel.com/T/#u > > Changes since V1: > - Add documentation suggested by Jarkko. > --- > arch/x86/kernel/cpu/sgx/sgx.h | 2 ++ > arch/x86/kernel/cpu/sgx/virt.c | 4 +++- > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h > index 0f17def9fe6f..b43582da1bcf 100644 > --- a/arch/x86/kernel/cpu/sgx/sgx.h > +++ b/arch/x86/kernel/cpu/sgx/sgx.h > @@ -28,6 +28,8 @@ > > /* Pages on free list */ > #define SGX_EPC_PAGE_IS_FREE BIT(1) > +/* Pages allocated for KVM guest */ > +#define SGX_EPC_PAGE_KVM_GUEST BIT(2) > > struct sgx_epc_page { > unsigned int section; > diff --git a/arch/x86/kernel/cpu/sgx/virt.c b/arch/x86/kernel/cpu/sgx/virt.c > index 6a77a14eee38..776ae5c1c032 100644 > --- a/arch/x86/kernel/cpu/sgx/virt.c > +++ b/arch/x86/kernel/cpu/sgx/virt.c > @@ -46,10 +46,12 @@ static int __sgx_vepc_fault(struct sgx_vepc *vepc, > if (epc_page) > return 0; > > - epc_page = sgx_alloc_epc_page(vepc, false); > + epc_page = sgx_alloc_epc_page((void *)addr, false); > if (IS_ERR(epc_page)) > return PTR_ERR(epc_page); > > + epc_page->flags |= SGX_EPC_PAGE_KVM_GUEST; > + > ret = xa_err(xa_store(&vepc->page_array, index, epc_page, GFP_KERNEL)); > if (ret) > goto err_free; Acked-by: Kai Huang -- Thanks, -Kai