From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from DM1PR04CU001.outbound.protection.outlook.com (mail-centralusazon11010015.outbound.protection.outlook.com [52.101.61.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5583A21D596 for ; Sat, 23 May 2026 03:05:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.61.15 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779505552; cv=fail; b=RnxhNDp5EgBocVJDmGI/Xn1JEt3OKL+/LUuQJBm3/b4Vp5+1+L8j2HytIT32AXbY9r5vatF510l1cobwxwJrsFuie3+3rHV8GT5EIScBBUFb/hb97+z4A92nNAh42F9t4YJvFYsirKeHiYL98EkbajLW0iuFNk6dVph13JQJdJQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779505552; c=relaxed/simple; bh=XOfgc7cuJjIPG0mjWjqxCdcCzrB3ODxlKiC92jSo8A0=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=VnTqTLPdwl4kEEObKZgvptQNVb5LXQzVR2XUmlu5slajEnrb7WQcgwWlROvDQCx/A7u87dCGYbu2k/GULOzm9TvOEJ9pi42TN5MMbh/f8n4YrJjMkjxn4zl/KM5SBYk1upJ7jTZ85r+gvUbXZEdtWnFJMaxcGukPJ9Pnus7v17M= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=W6EDtdl8; arc=fail smtp.client-ip=52.101.61.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="W6EDtdl8" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=nNdx6Kc5BDPOOveK3qPypOc81y/gSez5kruB2FX9QTj5vzhMpc+M+dM4Bs/9WdtwmQ8csMQs3jgNAOnPXcL/CjJaZFoKq41HsLXefj1MwUfrGaE7Vq27H/3CdHrDMUmEWbsfkZ2fwBfsnS2jqIUNd/4rZWfakipoyg13dIq7+emlQ4abFnlVMoQm0prTZjx0eDkn07xnUlv3MswRMnkzXKRR5gYV00DucjruDRxPtAoJHp+90o13cQB+DuVNi0nRo3GLs1io8aCiSYkR+wDLV73hkLxoKTQtBssmx2coyZ/jN+XsQqpb7Boq89SvDxQrSyUmkTy04UBVnLWBRTFNyw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=/hG69HPeY7Ulafi9Isz0dvij9M2QPj1UZKRg/9iaNPg=; b=cy67YBAHmSFxEBpXKhBobXLM8JofRaWiPwmDpKzW+n/6s5mELXBJggaLQ6h4wiKHgV86/9Fww4jXC9B95PRAp24fuVjeGGn1ICdnMHYO9cZrWp1OYKUQcJhrD/u/yFwm29jFvHTOy4rpiGaCQna6uqvtYWM3IyCDKq54Uj3RkVbqr0jx++C/v4sF20ktol1sCxrbiqhwaRcG4rKWFq8F1NIhU+aWx3rxYmxkQNRuAWT8twtipfQT1L1SNhCTqaGSPsPf8zGK12SvTfkuuaAjQpA4pQhv8zZL29B/fOLt8yP/Kchgss1qATCii0hlKPpEBFeSuY5xjWxRQSv8+FhQHg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=/hG69HPeY7Ulafi9Isz0dvij9M2QPj1UZKRg/9iaNPg=; b=W6EDtdl8yl7V4jgEnTb2pLcBWarVSnTlu/m45LnWxs95THWsTKhJa3GPE6eXCupWdDgiatFWWJe/wO6kusqC9WHWF0tr/ZKB+SY0oqpJv+w2J9w4Q0zeUxPYl4S0wzerWA9qR1d+y4kFgRZ0+9FXv8308Sk7WHPBy4cgzmSkymsTevjVRtcOp7fq4aosdGye073X6r7AJ8nXa4dB97Usynk1TlXQbGZs45UdCm9rELlGNKOagz8IPYckd+jEKuREBRdMayvQ/XZp5DsSV5JWNuSri+fYinqvt39q+BNj285KFqoTB+ufPHLPaBPFeynb7pF7/5GB9zagM6lcso3qnA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from DM3PR12MB9416.namprd12.prod.outlook.com (2603:10b6:0:4b::8) by DS7PR12MB6263.namprd12.prod.outlook.com (2603:10b6:8:95::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.48.17; Sat, 23 May 2026 03:05:46 +0000 Received: from DM3PR12MB9416.namprd12.prod.outlook.com ([fe80::8cdd:504c:7d2a:59c8]) by DM3PR12MB9416.namprd12.prod.outlook.com ([fe80::8cdd:504c:7d2a:59c8%5]) with mapi id 15.21.0048.016; Sat, 23 May 2026 03:05:46 +0000 Message-ID: Date: Fri, 22 May 2026 20:05:44 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 17/20] gpu: nova-core: vbios: remove unnecessary fields in PciRomHeader To: Eliot Courtney , Danilo Krummrich , Alice Ryhl , Alexandre Courbot , David Airlie , Simona Vetter Cc: Alistair Popple , Timur Tabi , nova-gpu@lists.linux.dev, rust-for-linux@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <20260519-fix-vbios-v4-0-5d3f210c5602@nvidia.com> <20260519-fix-vbios-v4-17-5d3f210c5602@nvidia.com> Content-Language: en-US From: John Hubbard In-Reply-To: <20260519-fix-vbios-v4-17-5d3f210c5602@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SJ0PR13CA0066.namprd13.prod.outlook.com (2603:10b6:a03:2c4::11) To DM3PR12MB9416.namprd12.prod.outlook.com (2603:10b6:0:4b::8) Precedence: bulk X-Mailing-List: nova-gpu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM3PR12MB9416:EE_|DS7PR12MB6263:EE_ X-MS-Office365-Filtering-Correlation-Id: c7f6fed6-4003-41ee-c40e-08deb8782f0a X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|22082099003|56012099003|18002099003|6133799003|4143699003|11063799006; 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:DM3PR12MB9416.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(22082099003)(56012099003)(18002099003)(6133799003)(4143699003)(11063799006);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?aEtqb213aFVEeEdDb3M5TXVPVGcxL3BPb3hZeFBHL3JpZzkwM1JkTWZnLzZS?= =?utf-8?B?SjVIOTRtZHdzRWo0ckVla3N0Z1JXNzNNSnNZZjU0dXN5djNybFE2RURRcXkr?= =?utf-8?B?TytjN3F3ZWQ1YitDYTFzM0xCZHV3ZE1POVNaWGV1bTNsc2w1cFNMRWoyT1c1?= =?utf-8?B?RlVFSmhTaDhPTzE2cHl2YlN2ZUsvRlZkcGQzOWdlNkVVd0tEN0lQNUFJNGdR?= =?utf-8?B?WDQyWStxdWtYZHg5WUxaSGZjd1dsSkNQZVVGNVo5RFNvTFRNNGNHa29yUEJm?= =?utf-8?B?TVRYYzVnYkJySWVZRlRzNVRDVmNaRXNUcnUwVUNkb3c1dERZUmR4UThkTGVF?= =?utf-8?B?VzA4ak1ROE0rekhyREpYandVNGdhWE1kOXZFM3pRYW9GYXdhT3AvYWY2eVJv?= =?utf-8?B?RnR5NnAyRzRtdXFVOTNoVUpPRGN0SC95ajN3S0ltTEhVRDBxZzFqK2srejk0?= =?utf-8?B?WkhNSEpCbEFuNitxQnkzTlRXc1FWamRoOTMzVnpYdThJL1h1MkNsbyt1TS9p?= =?utf-8?B?dWMyQWRiMWNsN0JzNkFNcUt3Q3BFcTg1ZTE0dElPSStXRTlLd1pWZHd4OWRQ?= =?utf-8?B?NTVreXpLejY5K3h6WDBiWmRiWVZWZzhLZFZXV1dMK2IySzJJMDVyQWJuemYr?= =?utf-8?B?OWVqUk0rZkhuTWo3Vmt6THdXR0FWa3lraklHYzB6ZHNLdnpGZWp6aFhEWWNM?= =?utf-8?B?dFQ5VE4ya3B1Y2RwRVc4Vll6ZG9rSDI0SFdXUHJlTmZsTEhhNEc4LzRXVXpu?= =?utf-8?B?NzNCc2ZQQm9Qb3ZWamdlcElTTHQ3cVZ2bHVYdTA5eVp0Q29nb0xlM3pRcGIx?= =?utf-8?B?Y1NtNFFZMnNiYjFIaTVTNDNKQUxrcEhPRnBQQjBZVi8zejRxZTZSSlltd3RM?= =?utf-8?B?OTdHejYrYnZVM0xGZDloL05yc3BwNzFIZXhmQWlNODFkVWZrQjdQaHcvMmpJ?= =?utf-8?B?RFFXbVdVTXVMZE1POFRoQS9MTTJKVlk4SGtjcVR5WTByVUF6M3JhTXE4Q3Jj?= =?utf-8?B?MFpVN3ZOM2pGM3VMaFdGcHdvd2FSLzNjWktmYnArY0ZFM0p2ZjBHb092b0Nh?= =?utf-8?B?Q1FlKzA3T3ZoS2RkVnNVaFBCU1FJTE14TzJyWk1XM04xWm1jUFdHZTl4U1B6?= =?utf-8?B?OWdXU1Jid3YzS3dVTENITGJHVXltY0luZDNDUlhxNFlzYjc3TGp6TWk1Wllq?= =?utf-8?B?d3FxYXAzVEJKREhQdlYyT2l3akpEQ2xEWGZGUEJDTVl0WE9DZVpMUjZtTXF3?= =?utf-8?B?ZzdzcEo2SmNQT3Z2Rk1hZXVlenJhbXErVlhFL1NNa29oOXprci9LSW5ReTFN?= =?utf-8?B?WCtHSlFyanNvbUJKZldUVDBwTzBDMmVTQTdVNlNwMCt5dGZMaG9GNVpqekE2?= =?utf-8?B?SjVESVo0WU1YQ3dpbEdvcVdYS0FhNWNsNmluU1ZGaWZ3dVkvc3grNzZOUUN5?= =?utf-8?B?N29uOU5ldWJmeTg4SDlyTFFXcm9PckxQajd6aENMUEJ3NlM0eUlZWXBRUlUr?= =?utf-8?B?RHFWTHZ1RG9yQit3RnNKMHNKYUtteEpjMXhNbnh1MTBlZlVuYVRUcWtwRXZs?= =?utf-8?B?cDkrbUt1SjF0NVB5ekxkUlk3VUtldWpQRitncFUxa2x3dlhsNjB5THYvVmJv?= =?utf-8?B?NGhoQnM2U1V3RnE1am1ScEdQOFFsTWFJcFZpWFJDMmkxbnZJdTZUTTJRUXMx?= =?utf-8?B?K2VOUVN6SE5NSG91YVRJVi93dnR6NlVSbktzeWxpUWQ3ZmFFUWlwTWp5bkVH?= =?utf-8?B?MHJxYi9RS3NlOVdxZ1dwdEVRSHU1d2R3ZGZyUlYxNlJjSUhhM0ZYUXJZWml0?= =?utf-8?B?RDlCZTFMdUtlbTlnZVFBRXVSc1M2VkdpeExjSStnZVdXa1NiRmE2VnNWZWVI?= =?utf-8?B?TVNCb0h2bG9VbjVoTzVjR1FEd3lvWmVheUpEeSs2VDQ3NUIxUC9KRjlBbU92?= =?utf-8?B?MTUyQ25NeklrVXVJMlBIU1ljbjdtUUJyR2ZGMGczZEw0SXlWdXhVNFpEb3Bp?= =?utf-8?B?S200UjlQNjg3VmwzWDBvVW5ISXdqczVWRkJ0bURTS0FyT3R2KzUrTThXNnVD?= =?utf-8?B?SjdvVjE2OVYyYUxHYmJGNkQyQkx2SzYrcGhpY2llZW1NTVZPcHB3RVVQdGo3?= =?utf-8?B?alRXanAwVTkrZkdxdUlJMmtWQjN2Q2hWcGMvTFI4Y1hCVERtcnlWaXQ2VDVP?= =?utf-8?B?aTY2RHpvMDQ0WmwwcVgyalZKc0pKc1RIRzZlQkZIWU5aWml6TEI4REtMYWFQ?= =?utf-8?B?Q0dNVm43MCtsNlk3K0VOck1lU3pZVW1mb2s1cTBpc21pbXdkQUhuc01hWk55?= =?utf-8?B?cHJ4U25ucFRiaUlnVVNwandwYmZHK1Z4WnZ2ZW9wL3VNdWFKOFhmQT09?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c7f6fed6-4003-41ee-c40e-08deb8782f0a X-MS-Exchange-CrossTenant-AuthSource: DM3PR12MB9416.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 May 2026 03:05:46.0702 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: KenCx26ahQfim2TVVi8/uiPeaPgeLPppC61RG2J8C1ZeQQl39K6SIiI+duTqJalCFrfBan000CrvdzMtx2wpbw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB6263 On 5/18/26 7:55 PM, Eliot Courtney wrote: > Remove unnecessary fields in PciRomHeader. This allows a simplification > to use `FromBytes` instead of reading fields piecemeal. A lot of these > checks were redundant as well since it checks the size of the `data` > first in `BiosImage`. > > Signed-off-by: Eliot Courtney > --- > drivers/gpu/nova-core/vbios.rs | 68 ++++++++++-------------------------------- > 1 file changed, 16 insertions(+), 52 deletions(-) Reviewed-by: John Hubbard thanks, -- John Hubbard > > diff --git a/drivers/gpu/nova-core/vbios.rs b/drivers/gpu/nova-core/vbios.rs > index 64d100b6699b..1dca7933fac5 100644 > --- a/drivers/gpu/nova-core/vbios.rs > +++ b/drivers/gpu/nova-core/vbios.rs > @@ -546,67 +546,38 @@ fn from_id(image: &PciAtBiosImage, token_id: u8) -> Result { > > /// PCI ROM Expansion Header as defined in PCI Firmware Specification. > /// > -/// This is header is at the beginning of every image in the set of images in the ROM. It contains > -/// a pointer to the PCI Data Structure which describes the image. For "NBSI" images (NoteBook > -/// System Information), the ROM header deviates from the standard and contains an offset to the > -/// NBSI image however we do not yet parse that in this module and keep it for future reference. > +/// This header is at the beginning of every image in the set of images in the ROM. It contains a > +/// pointer to the PCI Data Structure which describes the image. > #[derive(Debug, Clone, Copy)] > -#[expect(dead_code)] > +#[repr(C)] > struct PciRomHeader { > /// 00h: Signature (0xAA55) > signature: u16, > - /// 02h: Reserved bytes for processor architecture unique data (20 bytes) > - reserved: [u8; 20], > - /// 16h: NBSI Data Offset (NBSI-specific, offset from header to NBSI image) > - nbsi_data_offset: Option, > + /// 02h: Reserved bytes for processor architecture unique data (22 bytes) > + reserved: [u8; 22], > /// 18h: Pointer to PCI Data Structure (offset from start of ROM image) > pci_data_struct_offset: u16, > - /// 1Ah: Size of block (this is NBSI-specific) > - size_of_block: Option, > } > > +// SAFETY: all bit patterns are valid for `PciRomHeader`. > +unsafe impl FromBytes for PciRomHeader {} > + > impl PciRomHeader { > fn new(dev: &device::Device, data: &[u8]) -> Result { > - if data.len() < 26 { > - // Need at least 26 bytes to read pciDataStrucPtr and sizeOfBlock. > - return Err(EINVAL); > - } > - > - let signature = u16::from_le_bytes([data[0], data[1]]); > + let (rom_header, _) = PciRomHeader::from_bytes_copy_prefix(data) > + .ok_or(EINVAL) > + .inspect_err(|_| dev_err!(dev, "Not enough data for ROM header\n"))?; > > // Check for valid ROM signatures. > - match signature { > + match rom_header.signature { > 0xAA55 | 0x4E56 => {} > _ => { > - dev_err!(dev, "ROM signature unknown {:#x}\n", signature); > + dev_err!(dev, "ROM signature unknown {:#x}\n", rom_header.signature); > return Err(EINVAL); > } > } > > - // Read the pointer to the PCI Data Structure at offset 0x18. > - let pci_data_struct_ptr = u16::from_le_bytes([data[24], data[25]]); > - > - // Try to read optional fields if enough data. > - let mut size_of_block = None; > - let mut nbsi_data_offset = None; > - > - if data.len() >= 30 { > - // Read size_of_block at offset 0x1A. > - size_of_block = Some(u32::from_le_bytes([data[26], data[27], data[28], data[29]])); > - } > - > - // For NBSI images, try to read the nbsiDataOffset at offset 0x16. > - if data.len() >= 24 { > - nbsi_data_offset = Some(u16::from_le_bytes([data[22], data[23]])); > - } > - > - Ok(PciRomHeader { > - signature, > - reserved: [0u8; 20], > - pci_data_struct_offset: pci_data_struct_ptr, > - size_of_block, > - nbsi_data_offset, > - }) > + Ok(rom_header) > } > } > > @@ -722,11 +693,11 @@ pub(crate) struct FwSecBiosImage { > /// BIOS Image structure containing various headers and reference fields to all BIOS images. > /// > /// A BiosImage struct is embedded into all image types and implements common operations. > -#[expect(dead_code)] > struct BiosImage { > /// Used for logging. > dev: ARef, > /// PCI ROM Expansion Header > + #[expect(dead_code)] > rom_header: PciRomHeader, > /// PCI Data Structure > pcir: PcirStruct, > @@ -771,15 +742,8 @@ fn is_last(&self) -> bool { > > /// Creates a new BiosImage from raw byte data. > fn new(dev: &device::Device, data: &[u8]) -> Result { > - // Ensure we have enough data for the ROM header. > - if data.len() < 26 { > - dev_err!(dev, "Not enough data for ROM header\n"); > - return Err(EINVAL); > - } > - > // Parse the ROM header. > - let rom_header = PciRomHeader::new(dev, &data[0..26]) > - .inspect_err(|e| dev_err!(dev, "Failed to create PciRomHeader: {:?}\n", e))?; > + let rom_header = PciRomHeader::new(dev, data)?; > > // Get the PCI Data Structure using the pointer from the ROM header. > let pcir_offset = usize::from(rom_header.pci_data_struct_offset); >