Received-SPF: pass (google.com: domain of linux-kernel+bounces-4233-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Subject: Re: [PATCH v4 6/7] firmware/efi: Process CXL Component Events
To: Ira Weiny <ira.weiny@intel.com>, Dan Williams <dan.j.williams@intel.com>,
 Jonathan Cameron <jonathan.cameron@huawei.com>,
 Shiju Jose <shiju.jose@huawei.com>
Cc: Yazen Ghannam <yazen.ghannam@amd.com>, Davidlohr Bueso
 <dave@stgolabs.net>, Dave Jiang <dave.jiang@intel.com>,
 Alison Schofield <alison.schofield@intel.com>,
 Vishal Verma <vishal.l.verma@intel.com>, Ard Biesheuvel <ardb@kernel.org>,
 linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org,
 linux-cxl@vger.kernel.org
References: <20231215-cxl-cper-v4-0-01b6dab44fcd@intel.com>
 <20231215-cxl-cper-v4-6-01b6dab44fcd@intel.com>
From: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
Message-ID: <a32464b2-9810-ca9d-73e5-4ed4cf69fea0@amd.com>
Date: Mon, 18 Dec 2023 10:13:16 -0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101
 Thunderbird/78.4.0
In-Reply-To: <20231215-cxl-cper-v4-6-01b6dab44fcd@intel.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0:
	=?utf-8?B?VFFPMzFwcU5keHhpTWU3WitPc3BRbExXQk9Rby9aZjREcTJXR0RZWlkzMUhS?=
 =?utf-8?B?dDFrTy9yWjZ0QWZienAyblJmUHVOOE5ZKytXUk1NSzJBSkp2aTZUQXAxbWla?=
 =?utf-8?B?ZFhhMFRDZEZOb1ZVaC9aNHNDUy9iOTl2NExJT0dQNkRMbG1peTN5MUVpcURk?=
 =?utf-8?B?bnE4THRud2ZSeXB4dzViaW9iNG1tL2p5Qnk5ZTZYVkYxZkJ2RERVbmwwKzh4?=
 =?utf-8?B?aE9vVUI3aWkrUzQvQ0xySG9YZitXT2NqQ2lCZlpjUG1Ja1dlcnRqd1JrRkhM?=
 =?utf-8?B?aFh2bjVaZDhuT1l3VHBHVnN6eDBqSnRNOFk1eGJ2VEtSb0pxTnc2dXhyQ0VC?=
 =?utf-8?B?YlhhcEprWE5ETVNBcnhhemdvMzJENjFHaFByQVFTQmVDc1VFdmYwVFJwUUE3?=
 =?utf-8?B?eE5PNDBOODFkWmhtemgrMmowME10LzhNdXM4NDRpOWtKUmI1dWVCMkRnTzJv?=
 =?utf-8?B?azBOOFRLS20xSnRVaXRMaHQwL05LQVQrbkpXR2c2em9MYlBONW1CdStoQWVW?=
 =?utf-8?B?L3JCN1pjUFJVSEJXUUkxVnV3WXU5YlFCeXRwakZIRWIxWjlaVXliWExyY0Qz?=
 =?utf-8?B?NWcvbVB0Ny90bGp1N1FpUHBpbVFXL3VOMzJZWjJEWkh2Y1J6VjF6TFhsSi9X?=
 =?utf-8?B?RG1CWDdrN2JCakE5emxxSVZjK0lRNTZwZlZSQmtrOEQvVnlKSjd3N0VDdnYr?=
 =?utf-8?B?ZHFjWkhkZW15dVd1azZ3OXFKZk1xNUtzRElibjFBUnJia2dkVFNteWFaYlkx?=
 =?utf-8?B?UjRROWIzQ09SWHF3Ni82dW9mODNNUVo1bERieUZrbmcveDNhQ0ZIM0ZtMkJJ?=
 =?utf-8?B?elpWN0JvbWs3T0JjZFdjL05YWm1LMHhDWXplOXRmUVU2T3JkREtXWVE1ZnJx?=
 =?utf-8?B?VndzdHpwQlNoTldkOVJtWkt0MkNSQTAxL0Z4Mkw2Tm96R0gzWG5ydEw2T3J4?=
 =?utf-8?B?QnZPUkt2cFEweEFaOW1XSitUZTFmMVdaUEU4c3V2bG40U00xMHFBbjE1dXNQ?=
 =?utf-8?B?M0VaUTZTeGwyVXBBS3Rnelg4dDNxK1BxT2NBSFpXQ3VKRUZ4R3VnSXozUHRw?=
 =?utf-8?B?YWt4ZW5YK0Q5Q3JsZ01JTTFIOFBVZmFBVmpPN0JwU3pXZHJISGxnKzdXQ1FS?=
 =?utf-8?B?UUhvdkloc1FGWXhGUnhSWFY2eWFlM1duZW5XUEsxbFBhV0JIc1JvSVZrM0wx?=
 =?utf-8?B?QlNCd1pyVVFjdGF4UmgvR002aXlhczRzaG1FQUxzeTZHWGUyK08rVjNLVnlo?=
 =?utf-8?B?cnVTVGk4MUx3MmZjbmc1MitXa2tlaTl0TUVwNGlYd2poUjZEWmh1VzY0S09D?=
 =?utf-8?B?OS91dXNjaDZDU1dkWHAzMXpiYmtsNEVYM1NkbEgybENwelAybEVqdTh3Uzd0?=
 =?utf-8?B?a1p2QVBrUmMxQnY5WEkvNkd1RFR6WnZIS0pQRVp2bGo5aWZaQXhxeWFrVzgv?=
 =?utf-8?B?RGJXSzg5VGRNcWxzWVRrSndtUXVFTEN5U3RVTkxVNEFZSFdzU2Y0UkZaR1I4?=
 =?utf-8?B?bmVvU2Mxc2tmWEx2KzgwTDYweWEwRHB5dXVIYVhpZmIrOWdOYy9odlBub1h3?=
 =?utf-8?B?TlBhcGp3d3VWcGRTT2p6U0I4ZjMzQkdHbkZFUFVlYmJxZ2NVUS9XdHpza1pu?=
 =?utf-8?B?RE91THlJdDM2VDk2cmI4L0d3UUJnYjdRdlVaVmVoTUZ0KzNHbE9Nb0Fra1BJ?=
 =?utf-8?B?ZHpBZWFMYmV4MGdwcFBzeDZZWVpZT1BCQ3NTREtoN1U1di9nZzlSUW1pYVJM?=
 =?utf-8?B?K1ZJWWNhSFZxLzNpU0VGaHlnRFRPWXpMeXh2UDFkOCs5Y2tCakZ6c0FiL1lP?=
 =?utf-8?B?ZFRyVEVqaTRKeElTSzdic0VJV2kzZW9keUV0bXRock5kYXpZWkpVY3Y2UGxX?=
 =?utf-8?B?d0N2NCtRRGkxZ1V1a1BmS0E4WXVsUklsaHNBbTZpSTk4ZEIxRGtac0ZXcFBV?=
 =?utf-8?B?ZHFzeEhwOXUrODRXZlh2dWNUU29pd0tuSWV1cTBsZHdGSEFBRHh6aVJqY1k2?=
 =?utf-8?B?UFhEU0QrSWpCMkkwQWZQdHB3MERtUFVJUEkyU1oxaUEwN2picVEyT0FvRFo2?=
 =?utf-8?B?SWF2Z21tRFJHZm00Ym1CNmlhdlNmdFVKd2RaWGpUWFBlUDA3K0RKQkdMaUth?=
 =?utf-8?Q?4qdtQQUuyA7qp6Rw1mHLUfhNu?=
X-OriginatorOrg: amd.com
X-MS-Exchange-CrossTenant-Network-Message-Id: e6321d2c-42b4-4a2a-5652-08dbfff502c5
X-MS-Exchange-CrossTenant-AuthSource: BYAPR12MB2869.namprd12.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Dec 2023 18:13:18.5425
 (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: HxrIjL9fmc9RCwetU7+j8yCn54kactRDtfF02so/57JGtuMqjOfNnKRTJs96JAkL0/exx55Mss7swuf9nQncQw==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW6PR12MB8959

On 12/15/2023 3:26 PM, Ira Weiny wrote:
> BIOS can configure memory devices as firmware first.  This will send CXL
> events to the firmware instead of the OS.  The firmware can then send
> these events to the OS via UEFI.
> 
> UEFI v2.10 section N.2.14 defines a Common Platform Error Record (CPER)
> format for CXL Component Events.  The format is mostly the same as the
> CXL Common Event Record Format.  The difference is the use of a GUID in
> the Section Type rather than a UUID as part of the event itself.
> 
> Add EFI support to detect CXL CPER records and call a registered
> notifier with the event.  Enforce that only one notifier call can be
> registered at any time.
> 
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> 

[snip]

> +	struct {
> +		u32 length;
> +		u64 validation_bits;
> +		struct cper_cxl_event_devid {
> +			u16 vendor_id;
> +			u16 device_id;
> +			u8 func_num;
> +			u8 device_num;
> +			u8 bus_num;
> +			u16 segment_num;
> +			u16 slot_num; /* bits 2:0 reserved */
> +			u8 reserved;
> +		} device_id __packed;
> +		struct cper_cxl_event_sn {
> +			u32 lower_dw;
> +			u32 upper_dw;
> +		} dev_serial_num __packed;
> +	} hdr __packed;
> +
> +	union cxl_event event;
> +} __packed;
> +

For some reason, prefixing the struct name with __packed attribute seems 
to do the job. ("__packed device_id" and "__packed dev_serial_num").

Thanks,
Smita