Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <02010d9b-b452-3577-dd1d-7013027a09ce@intel.com>
Date:   Wed, 6 Apr 2022 10:50:42 -0700
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101
 Firefox/91.0 Thunderbird/91.7.0
Subject: Re: [PATCH V3 17/30] x86/sgx: Support modifying SGX page type
Content-Language: en-US
To:     Jarkko Sakkinen <jarkko@kernel.org>
CC:     <dave.hansen@linux.intel.com>, <tglx@linutronix.de>,
        <bp@alien8.de>, <luto@kernel.org>, <mingo@redhat.com>,
        <linux-sgx@vger.kernel.org>, <x86@kernel.org>, <seanjc@google.com>,
        <kai.huang@intel.com>, <cathy.zhang@intel.com>,
        <cedric.xing@intel.com>, <haitao.huang@intel.com>,
        <mark.shanahan@intel.com>, <hpa@zytor.com>,
        <linux-kernel@vger.kernel.org>
References: <cover.1648847675.git.reinette.chatre@intel.com>
 <bac6e77fe04100d6bfebd4e13aa9b916f82bfea6.1648847675.git.reinette.chatre@intel.com>
 <Ykvqf3Ws6jlN5g+p@kernel.org>
 <b41d81ebcb6934765d7f37d4ce95baa16ec9b5d2.camel@kernel.org>
 <d8cc2142-c50d-fbd9-425f-01e279c9a0f1@intel.com>
 <94f62e19a630792f78e3c48895dfb792ecb02c6c.camel@kernel.org>
 <70962fc4-1624-2fd8-4d8d-f1a31001e165@intel.com>
 <55cd5349e58c44113ae976e04ea4c6dc0cfba66d.camel@kernel.org>
From:   Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <55cd5349e58c44113ae976e04ea4c6dc0cfba66d.camel@kernel.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?WGNvK2dPRVhpTnErZ1B4VWt1K2FYQzB1MU9ZUWZaMFR6WHRIN25nYVBFQ1JE?=
 =?utf-8?B?V3lOeWRkTStsYk1MZ2VGVDZFbXYxdVRMb1BycUtjWVIrb0V4TFpPdDEwbmtQ?=
 =?utf-8?B?cC9uOVl5bGxTQk9TbDQxeHJKMzdPeGRDWEhDMXQ0MTJFeU1BTDNqV1hUaDFt?=
 =?utf-8?B?MTRYa1dUNjRJMmVWKzhjSGFJa1ViL2d5U2g1SlhRN1B0OWJwaG9uNDNXckVW?=
 =?utf-8?B?eG1ZMDJaTXVqdFhWZmI0enFpYlBFMm5hMm9CRkN3QkZFcFFUYmVpdEFCMG5p?=
 =?utf-8?B?elJGc28zUkJRbHdVYnBJTFRkSUNqdGJrdXFnUWVzVUpwRTV0VWFzVGg0WDVD?=
 =?utf-8?B?N3ppcWJSSncxWFU5QlJobmdVRE1DWFJnZFVUTXpremh1U2hDQUZ2YUJ5S3R1?=
 =?utf-8?B?SFc3Q3h5ek5sekhZM3E0WEhzWmpoaG0xUG0yQ01QZjhpWkNqUjZSQ1c4czBu?=
 =?utf-8?B?cDNHMEo2YTVFNk1zMDlVbU91SEFGZzNoU0lvMTE1QXdiLzRPdU1FMFh0aGk4?=
 =?utf-8?B?MjlHczJpVmxiaWdiaWhHL0VHV3VzZ2U0Q1NqYXFBZHFaYU1LZmxISXFOenRQ?=
 =?utf-8?B?a1JrLzkrSnBBUCtNdzdkMXB0M0d3MVZJcWFpWDI1VUpKa1hvQTh2dEY2dG9O?=
 =?utf-8?B?WHBlQmdQYWxYclRoZ3ZWRUIyVTZPbi9hNzJIbjJibXZYMzN2V3pWWFJpdHRu?=
 =?utf-8?B?S2FuYmkweXg5em91eTVyY3h5cmRXZnc0MVdtc1NmUzZwTThlRWg0bFlkVlFO?=
 =?utf-8?B?TkplT1drTjc5SklERldrcEliY2tDTmN6TDZLcmJvOW1sNlFYeGYwQlh5MWxO?=
 =?utf-8?B?ZkxXSk1QMWNtTnZzTm8zajAwRGVZUVdydDVoV0laTmR6anRoQmV6NGdwUTg0?=
 =?utf-8?B?aGpWS3A3NTZjOUFRZC9rV3N4cUlLZ0hYM1YrMk8zd2svRDFFTHdLNW45T1JK?=
 =?utf-8?B?aVNlSHB2UjNxQ2FkMTdJa01va1l3T092aXlOKzhldVZiajlJWnRxQys1Mllw?=
 =?utf-8?B?ZFgyYmpITWdhcmN3dDVmRGQ2VE84VW5kZXBvVUV0aG5hVFhZaEY1bXdtSWgw?=
 =?utf-8?B?WHMwZEJoc2xSR2JIam5CcEJ0enpJYWhXM3Fub1VWUEcvM1RkQXRVcHFQdFgz?=
 =?utf-8?B?cmhXU3J3d0RnWUV0Z3dYelVFUmxFVXNMUFVmWjZoNnIyUUdwSktmcUJZR05E?=
 =?utf-8?B?dVd6b2lrREJodUdLNEFXWlNDUGQ4SFRhaFBzeHB5anVOcFlJWG1WbXhUOXRn?=
 =?utf-8?B?NTE2SjVXeldSMzZGNWJKWjVKMnU5Zk1JRGZiajR3a2tCQ0J0RUF5ZGNOTEdh?=
 =?utf-8?B?OTZJMDEwZEJHVVAvcHE5T3NnVWRRTGRNYlU4SHBFUVVOaGR4MWZBcDJHandP?=
 =?utf-8?B?QVlRdHVZZlBCTzRMSU01M1lNdUcxMytvNzVuNzRpbUUySzM5Q0lvMzZNcnlN?=
 =?utf-8?B?cjVuUy8vdmV2V3NrMUJvdlU1YWVNelhwVDJ5V01VSnlTdUhaZTBuNHVTRWdR?=
 =?utf-8?B?Q25kdlZGbkloNWxzZjlEZFplRnpwekZJWG9GaTY0UXJJYzB1bDk4bkJjbG9k?=
 =?utf-8?B?L3QyMnRwRW9udE8yWHNMNUFVYVBzYjhiMzJra0lZRzdJS2hnR1pDMGN0UzMx?=
 =?utf-8?B?MW03RnBmaXB4NU1vd2Ric1RSc1FBQW53M2dUK1cyRW5BQzZsTFJLdllpSktx?=
 =?utf-8?B?ZGlJODRUbXBlWGJoMWJLaCtNdkJiblhqbWFhdDJETzNUYWpDYzI5SFVzL0I0?=
 =?utf-8?B?SzZ6OXIyV3RoKzNuQTJGUWNJbllPRDlHejFMV0VpUFFuWFoxaGhWemhqTm9W?=
 =?utf-8?B?N2lSNEhNbFNGL3Z6MGJIZUg1SGgzNExVNkRXRys5UllrblE2WUM5ZTduRHNy?=
 =?utf-8?B?TmhVQk5ocUVpdk9waUE4Qm1XRXlyOUpRZWVIbzFZQmFjb0xtTjV5dGxpVm1N?=
 =?utf-8?B?WmZWeG1WaDliOW1XSjRuQWZFRDVJRTB0SFJPeDVISXRyQWc1YXVPMzhkUzV6?=
 =?utf-8?B?WDdHZXBJZFpSTEVjblpkSFd2QUdLUWM4ekI0YkJpaEJzV20yL3Y5eXJnNmlU?=
 =?utf-8?B?OEtSVE9RQm9hZi9Bb1QxR1kvMWI1TVpZRTFMWmxLclF4TVJpM0hkSWV1YjQy?=
 =?utf-8?B?RWtnY2JKdiszWCsvQlNSWVhzdldKK3ptZGk2T0JiZjV0UzErTkhKN24wa2c2?=
 =?utf-8?B?WkJON2t4K2VQeDQxL3IyTVU2bEFNekJ0VXhDb1VkNnNNeUFNUDgwN1RrSUNp?=
 =?utf-8?B?Uzg2MGxFWnZZTU9rRy9KWEtoUk5JNjVTNm41U0cwclVwdHYxM2NlTHUrdm1F?=
 =?utf-8?B?clZMK1c3Y1lOZlA2Q1ZZOHdjUlRaQ1FPVnVFZmdBYnZWd1RtcWR1NTZpVmsv?=
 =?utf-8?Q?xCIAZ/N60bW9PvF4=3D?=
X-MS-Exchange-CrossTenant-Network-Message-Id: 3e157cef-3559-42bd-bccb-08da17f5fa71
X-MS-Exchange-CrossTenant-AuthSource: BN0PR11MB5744.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Apr 2022 17:50:46.4405
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: /PZRk6+opuJRjz3dWc0V8GyiIr2Te78v98Yion2PFaquhrOwe37dlAqEujz0SDFGyAi6PyIJ8deOyKD/xhJFluIRXbYbZhHnF3Kq7W2vld0=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR11MB4348
X-OriginatorOrg: intel.com
X-Spam-Status: No, score=-5.7 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,
        DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,
        RCVD_IN_DNSWL_LOW,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE
        autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Hi Jarkko,

On 4/6/2022 12:32 AM, Jarkko Sakkinen wrote:
> On Tue, 2022-04-05 at 11:59 -0700, Reinette Chatre wrote:
>> Hi Jarkko,
>>
>> On 4/5/2022 11:41 AM, Jarkko Sakkinen wrote:
>>> On Tue, 2022-04-05 at 10:05 -0700, Reinette Chatre wrote:
>>>> Hi Jarkko,
>>>>
>>>> On 4/5/2022 8:34 AM, Jarkko Sakkinen wrote:
>>>>> On Tue, 2022-04-05 at 10:06 +0300, Jarkko Sakkinen wrote:
>>>>
>>>>>>>
>>>>>>
>>>>>> To be coherent with other names, this should be
>>>>>> SGX_IOC_ENCLAVE_MODIFY_TYPES.
>>>>
>>>> This is not such a clear change request to me:
>>>>
>>>> SGX_IOC_ENCLAVE_ADD_PAGES - add multiple pages
>>>> SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS - restrict multiple permissions
>>>> SGX_IOC_ENCLAVE_REMOVE_PAGES - remove multiple pages
>>>> SGX_IOC_ENCLAVE_MODIFY_TYPE - set a single type
>>>>
>>>> Perhaps it should rather be SGX_IOC_ENCLAVE_SET_TYPE to indicate that
>>>> there is a single target type as opposed to the possibility
>>>> of multiple source types (TCS and regular pages can be trimmed).
>>>>
>>>>>
>>
>> What is your opinion about what the ioctl() name should be? I prefer
>> to obtain a confirmation from you since you originally [1] requested
>> SGX_IOC_ENCLAVE_MODIFY_TYPE.
> 
> s/TYPE/TYPES/g i.e. SGX_IOC_ENCLAVE_MODIFY_TYPES is fine.

ok, thank you for confirming, will do.

>>
>>>>> This should take only page type given that flags are zeroed:
>>>>>
>>>>> EPCM(DS:RCX).R := 0;
>>>>> EPCM(DS:RCX).W := 0;
>>>>> EPCM(DS:RCX).X := 0; 
>>>>>
>>>>
>>>> ok, this was how it was done in V1 [1] and I can go back to that.
>>>
>>> I would name the fields as "flags" and "page_type" just to align
>>> names with SGX instead of trying to mimim "posix names". Otherwise, 
>>> I support that.
>>
>> I will move this ioctl() to use "page_type" instead of "secinfo"
>> within struct sgx_enclave_modify_type.
>>
>> Your guidance of "flags" is not clear to me. I assume that you
>> refer to the field for struct sgx_enclave_restrict_permissions
>> where I think "permissions" to only contain the new permissions
>> would be more appropriate. None of the other values in
>> secinfo.flags are relevant.
> 
> I'm fine with your permissions field to the restrict ioctl.

Will do, thank you.

Reinette