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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 81D95CD11DF for ; Tue, 26 Mar 2024 09:59:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1449B6B0083; Tue, 26 Mar 2024 05:59:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0F31C6B0089; Tue, 26 Mar 2024 05:59:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EAF476B008A; Tue, 26 Mar 2024 05:59:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id DA5C56B0083 for ; Tue, 26 Mar 2024 05:59:32 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 7FB97C09F1 for ; Tue, 26 Mar 2024 09:59:32 +0000 (UTC) X-FDA: 81938742984.27.0D74325 Received: from NAM10-DM6-obe.outbound.protection.outlook.com (mail-dm6nam10on2122.outbound.protection.outlook.com [40.107.93.122]) by imf08.hostedemail.com (Postfix) with ESMTP id 5970816001B for ; Tue, 26 Mar 2024 09:59:29 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=22v+cIq7; arc=pass ("microsoft.com:s=arcselector9901:i=1"); dmarc=pass (policy=quarantine) header.from=amd.com; spf=pass (imf08.hostedemail.com: domain of Vignesh.Balasubrmanian@amd.com designates 40.107.93.122 as permitted sender) smtp.mailfrom=Vignesh.Balasubrmanian@amd.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1711447169; a=rsa-sha256; cv=pass; b=SGQUQTdK1T7p+g4OftcPMFT6Gb2Nr3PfAkkQiX8EICp6y+8yVFoRCQWdNacTOA0KcMIm5Q SGn7dvkBKwrn4OX2472Utve4XC7nh/pPeDcbfAIXmRmFTC4Uoozn7dQzGaMApyqGfwb6xQ fZa3/6icXVbSkKxq3tZNRNSo3mEEW1k= ARC-Authentication-Results: i=2; imf08.hostedemail.com; dkim=pass header.d=amd.com header.s=selector1 header.b=22v+cIq7; arc=pass ("microsoft.com:s=arcselector9901:i=1"); dmarc=pass (policy=quarantine) header.from=amd.com; spf=pass (imf08.hostedemail.com: domain of Vignesh.Balasubrmanian@amd.com designates 40.107.93.122 as permitted sender) smtp.mailfrom=Vignesh.Balasubrmanian@amd.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1711447169; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=tR01Q869QWhv2sxVq6NhyDhx2q4aHlNyy0Wa0FZ7dTM=; b=P0/Bp58X0ReTBRGHCilO/x+2gj3SY2oS5v6aeQga6q+/edGT3t83jv0DvLyh7tY6udkfbm gDE5+ldPhjUIymji+yTNy2GSDliRcvllySBW99ZMwbQt44coRUM7kxidYucgx6/P3NrRBc 2wRrlCZR5qEZSmRhNttZ4IjfYIPp/sU= ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Wd9HWkGv25FlHx4iU5VsnYpq0YehiyqO4W9mOkJiIgOa27Ywdb0f3ZP2StH+ZYbr88N40zf+EwP42a2pLEIU5QKGSLZ9K1+cmwHdSzQ7j7rAH8+Y+/qj/Pl4fZ4RexdL3IKYIZ42enGJCvvzyil29E8NyH11qZ7HDYajABi8Wq6z11t8sxDNX6ncvgVJ+nkOmOInFdQaU2ZYiSoQYEBS3FKVnAPJ9PB07gNRTFW1xRujCPaDp8E4jQFXCD5RbQOgBZT/vizWJpKO6di/1DYTRmaJl0dAUCY+rHYr6Y28YL47KjLh5qN6QaXP3I21MCCXLId596x0FpsHd4lmUBPT3A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=tR01Q869QWhv2sxVq6NhyDhx2q4aHlNyy0Wa0FZ7dTM=; b=bsZ9+bnomHaUhpKpxO8owReazsQtbu1hI1mMqT+UNvnFizJ7yJKgw2oL4ddzCoNxlJ4nVtQSs3o2JxyFitaykF2eAoVH/+wwuclAhF/1FOBa/NBHNiFhjgnup5oYAZW1YIu0F+O141Cp1OHNFc2RCFX0uDL2qDLgvKWGwed39NJ593OOwMp0PgX/hDm2ZLV/DI/UKZvUuguCY77GLVYeq0LXaGUQtS4C/0KxxDJNu/DELHd8HP5Ihyt2/WTTBBpD8O6tIwnj+wQODHjD62MNB2nlRMUvpD684mXOwbcib2XIBZSfQboBJUZe9akc2kgnGzXHUe73lBdJCCRWOoyHUA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=tR01Q869QWhv2sxVq6NhyDhx2q4aHlNyy0Wa0FZ7dTM=; b=22v+cIq7aB/QHfLSO9U7uxKt1LhOHkSfRu0S/xzl7OMfZ7AE5elG3e0Z/5pxj4y5/92vAdS3OxUEQpTqF1gXBq7oYaomfcSgurhKXVTDGN/4evb8exOtOlIdQiGd1cjb3em6roCdyqSCf+OW/+7Ro6GS9kVyR6GZxCi0L8UYODM= Received: from SJ1PR12MB6124.namprd12.prod.outlook.com (2603:10b6:a03:459::15) by SJ0PR12MB5611.namprd12.prod.outlook.com (2603:10b6:a03:426::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7409.33; Tue, 26 Mar 2024 09:59:27 +0000 Received: from SJ1PR12MB6124.namprd12.prod.outlook.com ([fe80::c2c5:a349:ed66:b28]) by SJ1PR12MB6124.namprd12.prod.outlook.com ([fe80::c2c5:a349:ed66:b28%7]) with mapi id 15.20.7409.031; Tue, 26 Mar 2024 09:59:27 +0000 Content-Type: multipart/alternative; boundary="------------ZD84mwGO1vFg4iJmEJsFMFZN" Message-ID: <1b030dfa-e42f-4e45-8af6-e35bf4f1c393@amd.com> Date: Tue, 26 Mar 2024 15:29:14 +0530 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/1] x86/elf: Add a new .note section containing Xfeatures information to x86 core files To: Dave Hansen , Borislav Petkov Cc: "Balasubrmanian, Vignesh" , "linux-kernel@vger.kernel.org" , "linux-toolchains@vger.kernel.org" , "mpe@ellerman.id.au" , "npiggin@gmail.com" , "christophe.leroy@csgroup.eu" , "aneesh.kumar@kernel.org" , "naveen.n.rao@linux.ibm.com" , "ebiederm@xmission.com" , "keescook@chromium.org" , "x86@kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-mm@kvack.org" , "George, Jini Susan" , "matz@suse.de" , "binutils@sourceware.org" , "jhb@freebsd.org" , "felix.willgerodt@intel.com" References: <20240314112359.50713-1-vigbalas@amd.com> <20240314112359.50713-2-vigbalas@amd.com> <20240314160824.GDZfMg-J1VOyjxIMiV@fat_crate.local> <6ce6aa20-25d2-4784-823f-2a18f592e002@intel.com> <20240314162954.GAZfMmAnYQoRjRbRzc@fat_crate.local> <24f71d52-0891-4cfc-8dec-9f13ed618eee@intel.com> Content-Language: en-US From: "Balasubrmanian, Vignesh" In-Reply-To: <24f71d52-0891-4cfc-8dec-9f13ed618eee@intel.com> X-ClientProxiedBy: PN3PR01CA0093.INDPRD01.PROD.OUTLOOK.COM (2603:1096:c01:9b::21) To SJ1PR12MB6124.namprd12.prod.outlook.com (2603:10b6:a03:459::15) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ1PR12MB6124:EE_|SJ0PR12MB5611:EE_ X-LD-Processed: 3dd8961f-e488-4e60-8e11-a82d994e183d,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SJ1PR12MB6124.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(1800799015)(7416005)(376005)(366007);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?Ymt2LzlFVG4vZDlOQkNsU2hDT0txcXU0OGZNT3hIWnVsK3VOY2VXc2w3Zlgz?= =?utf-8?B?QnRtVUNOa0x2VmppdUp1VDVVNi9PNnp4cUF0YW90NjIvaW41Z1lQbXZlZ25D?= =?utf-8?B?R2J2T1RBNGl3TDg3endZZjgyR0krVEdXNGpIdkhSQWdlaHBzYmZpZDdkYkhN?= =?utf-8?B?aENnN3dlRmdCbkNmSkxNVnV3KzVZMTVRSGNjckpjVXNxZGZzOVFDTm5VblJX?= =?utf-8?B?YmliSlhNZU5tQWhXZVFmUTFYdVRqN0pJRm5ZbDZTNmFaTExXZEh1M20xKy9F?= =?utf-8?B?NUhrdFBNRzhrdzlBUGd2eEg2dHlyS1RlZXFSSXNrcXIyRFlHa045cnZlUGlO?= =?utf-8?B?NXlmQ3ZFRmNOTUpQNS9kMUNlNVpMak5wek15bHB1ajQvSU5UYWZJRVNiOHo4?= =?utf-8?B?UDE0bEVkeWlsZDlWaGtwTFU1dWFVdFpEa0ozQ2xmb3liTkFPd0RueC9xOWQ0?= =?utf-8?B?STdBZG53RTBMcndMeWV4QU9aNHl4c0Z1a2hNV0RPTGdPcUkwdjQ3MkxESWZ0?= =?utf-8?B?VXlUNTdCeHNPZWM3bTZNTHZsM1UrWk1YL1dHc2tBalJvbmxWT0VWOTJSWXRQ?= =?utf-8?B?K0d3SW5zekR3YkFxVDJEODRjaU9KNkk3dUhMS0Q2Z2owazNhZnBld3hsb2VP?= =?utf-8?B?Z1laTWdJYng3Zks4N3d2V0kxcEdRZlROUFRTWmRGdEFIKzRhbll2UVZRdmwz?= =?utf-8?B?UUx6NVJQSjUzUStELzR3N2RIUk5lUElWQlAydFg5WVdYSms0eTBNTzZRNHND?= =?utf-8?B?MEtRY0R2VTk3RXZXcWlhRkVNOTZOS2ZPRUhZZWs0WWFrZmNmRFI4Z1JpN3lq?= =?utf-8?B?UVNua01IM09Md0JlMUtteHBWMk5ERFJUa2ViaFprTmp4WTljNG9FVnRidVBa?= =?utf-8?B?ZWRQMHpmY0krSVRYOU9BNHYvQnY5TEFmSXdCWVJ5ME1NTjBXS3FjTFV1a0ZC?= =?utf-8?B?Q2llTTJNWXE4K3dmNTBGVm9SYitQNkdvT09QNXRZZnR5bjRSbHRHSThnUWY4?= =?utf-8?B?Y3ZvVitlM29KSHdaeWREajhaUUpWcHJYR2hWeTBKYkFsTnZJMWlrRS81OEQ1?= =?utf-8?B?enJ3ck5JOGRNRVYxdkYwZ21RYU5HMXIyellpSU5kbHhMTmVmZ3dBMmxCUHZB?= =?utf-8?B?d3JQS2NYRzdWUy9iMFZrZm9TQU1jZTdtUmJXQVB1SHNQb09xVVFVZEEvSCt1?= =?utf-8?B?N0pQYnNqRFUxL2tJSFRIa0x6TTY0L09ZWThwdU5KZDhMbkloWVptK1Y1ODJD?= =?utf-8?B?RExsMjZTS0hwYXZ5S0tISElmY0RzOGFCVlNXVWMrbXd1MEFWYXRONTh3Ujcw?= =?utf-8?B?RU9lcTN0YlF6dnRvN0czNUExNnpHTFNrbHQyWEVGZVhUSVVCTFVvcXlCZEMw?= =?utf-8?B?aHRJLzlEWU1nU01tRVM2VWx6ZkhqdHhSMGUrM1FGL0JoWHlLM3A2c3dpYUYr?= =?utf-8?B?THNSb3NyMHBGcHoyL3pZYmYwc2FvWnZwajBrcVE1cGxlWHlOd1lPcHpUSktq?= =?utf-8?B?djJ2REhBWnl5V1RKd283NUZaMDRSS1dlUmh0UXJYeURjazBueGt4VVF1TXRw?= =?utf-8?B?TndRN1RXVjdnUytQUlZKNGN2bTgzZ1UrZG51VWVXVUF2OUJxN0o1Sk9ucWEy?= =?utf-8?B?SjR4Y0Zwd0pDUXRPakpQeGdGa0tOUU5BSENSNUlmMHBycVN1dUwwblpmMjNn?= =?utf-8?B?am5QOUo4bnRzcVpNSWZZU2VNa3lWQlR5S0IxaEFSS2J2NG1PTkp5VlZaU2ZD?= =?utf-8?B?ZCs5bnlHK0RqUHZRVmJ3V29jQTR4SUp3NkJHWmVtZUpJVnp2UDJGSmlDbTJS?= =?utf-8?B?dHE4TXl3dk40TnByNU9KR3IxaGpOZlZOcXdsVE9ZVFBDeExMVCt2c2pjdVlI?= =?utf-8?B?dkZqeU5OVlpIQXZycDJBck1Eak5ZUjdYTklYSzBmaGlJRWc1TU14dDFtclBW?= =?utf-8?B?ZllnNlBNOTZ6NzVySEhIZTFUWVpxbHpWR3RpQ1doaDN2NUFLMzlCWjJwenU5?= =?utf-8?B?Zm0xMk1ka0dmWjNoQWRZQm81RWVsRkp0K1g5cDBuaUdYWE5jUG5lR2xNcWNq?= =?utf-8?B?RnJGQjFzVmMvWVVsY3ppcVVhYU0zdzdtQ2tJSHMwWWRzdHBLYTNjODdzUFE3?= =?utf-8?Q?FQjDIC8X9sbwk+3MNNjpLSgEH?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: e081a1f1-8c68-41b7-875e-08dc4d7b6beb X-MS-Exchange-CrossTenant-AuthSource: SJ1PR12MB6124.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Mar 2024 09:59:27.0129 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: +qyZ92WKYQmFEahytUz3WJNKxJPn9uNNQwrCnG90QR07R0QfqP0/h9LretfBTbpILNVfkMYSUf+bfrn0GVYz5Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR12MB5611 X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 5970816001B X-Stat-Signature: kii1k9h1x955p46gy3u6cq3ubdndmper X-HE-Tag: 1711447169-283044 X-HE-Meta: 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 lKUxyeYN 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: --------------ZD84mwGO1vFg4iJmEJsFMFZN Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 3/14/2024 10:09 PM, Dave Hansen wrote: > Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding. > > > On 3/14/24 09:29, Borislav Petkov wrote: >>> That argument breaks down a bit on the flags though: >>> >>> xc.xfeat_flags = xstate_flags[i]; >>> >>> Because it comes _directly_ from CPUID with zero filtering: >>> >>> cpuid_count(XSTATE_CPUID, i, &eax, &ebx, &ecx, &edx); >>> ... >>> xstate_flags[i] = ecx; >>> >>> So this layout is quite dependent on what's in x86's CPUID. >> Yeah, no, this should not be copying CPUID flags - those flags should be >> *translated* to independently defined flags which describe those >> buffers. > Ditto for: > > xc.xfeat_type = i; > > Right now, that's bound to CPUID and XSAVE. "feat_type==10" can only > ever be PKRU and that's derived from the XSAVE architecture. > > If you want this to be extensible to things outside of the XSAVE > architecture, it needs to be something actually extensible and not > entangled with XSAVE. > > In other words "xc.xfeat_type" can enumerate XSAVE state components > being in the dump, but it should not be limited to XSAVE. Just as an > example: > > enum feat_type { > FEATURE_XSAVE_PKRU, > FEATURE_XSAVE__YMM, > FEATURE_XSAVE_BNDREGS, > FEATURE_XSAVE_BNDCSR, > ... > RANDOM_STATE_NOT_XSAVE > }; > > See how feat_type==1 is PKRU and *NOT* feat_type==10? That opens the > door to RANDOM_STATE_NOT_XSAVE or anything else you want. This would be > _actually_ extensible. Thanks for the review. I will add new enum, instead of using "enum xfeature". Currently we are retaining the flags field. The value will be set to zero at this point, and the field will be reserved for future use. GDB / LLDB would not require this field at this point. Do let us know if this is not OK. -thanks, vigneshbalu. --------------ZD84mwGO1vFg4iJmEJsFMFZN Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 7bit


On 3/14/2024 10:09 PM, Dave Hansen wrote:
Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.


On 3/14/24 09:29, Borislav Petkov wrote:


        

          
That argument breaks down a bit on the flags though:

     xc.xfeat_flags = xstate_flags[i];

Because it comes _directly_ from CPUID with zero filtering:

     cpuid_count(XSTATE_CPUID, i, &eax, &ebx, &ecx, &edx);
     ...
     xstate_flags[i] = ecx;

So this layout is quite dependent on what's in x86's CPUID.


        

        
Yeah, no, this should not be copying CPUID flags - those flags should be
*translated* to independently defined flags which describe those
buffers.


      

      
Ditto for:

        xc.xfeat_type = i;

Right now, that's bound to CPUID and XSAVE.  "feat_type==10" can only
ever be PKRU and that's derived from the XSAVE architecture.

If you want this to be extensible to things outside of the XSAVE
architecture, it needs to be something actually extensible and not
entangled with XSAVE.

In other words "xc.xfeat_type" can enumerate XSAVE state components
being in the dump, but it should not be limited to XSAVE.  Just as an
example:

enum feat_type {
        FEATURE_XSAVE_PKRU,
        FEATURE_XSAVE__YMM,
        FEATURE_XSAVE_BNDREGS,
        FEATURE_XSAVE_BNDCSR,
        ...
        RANDOM_STATE_NOT_XSAVE
};

See how feat_type==1 is PKRU and *NOT* feat_type==10?  That opens the
door to RANDOM_STATE_NOT_XSAVE or anything else you want.  This would be
_actually_ extensible.

    

    


    

    
Thanks for the review.

      I will add new enum, instead of using "enum
          xfeature". 

        Currently we are retaining the flags field. The
          value will be set to zero at this point, and the field will be
          reserved for future use.

          GDB / LLDB would not require this field at this point. Do let
          us know if this is not OK. 

          

          -thanks,

          vigneshbalu.

        

    

      

    

  


--------------ZD84mwGO1vFg4iJmEJsFMFZN--