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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?FtI94esvHVPikeyGFtXOvFnEsxym4Wo3/5qb+iSee4d+X5TC1JBZQBkns7TR?= =?us-ascii?Q?/kNc364JqIw3A95cB+3nWsAqv7IaktFWc6N4Mn/0E5RuenmoIgnFNB4GMKTy?= =?us-ascii?Q?Km8lyBhIpl6Hadz44uY7dko4E7TZAM8isY3wEf3nqSRS/4Dmu08rd4E7L2cV?= =?us-ascii?Q?H2B6vfyIU/QZD/l83zbtPZZBKmPTb5kS/K5MLTXwzZanhdEyxX2SOvkFoXOo?= =?us-ascii?Q?1uCvInm6Z1jsqoUcKTGXL+U27hah3CcX2JZqVnOaMcybGWMR5cuQGoCKuT9i?= =?us-ascii?Q?70+D8ThkObPV7fLNg03LX5iS/kefhRi7BgtCjX4u9UUEqP1FFQIk49yqE+7C?= =?us-ascii?Q?YuuADMC/KDWPvtmYuIDogaCTZ9t63ne0MuaO4waYvHqSe5utgypoPXJaWM+6?= =?us-ascii?Q?uRTqR2p9AYz2vh7Avbzx8Wyb2aGqLSzl9vXmzaPE4ouo+qyouTqjGYjCGCgg?= =?us-ascii?Q?vRyE/3wvNNU69cDYnU1oYyWZSROSt5EY2okRlfwWExdO1iNJQYo8FPXPV1CB?= =?us-ascii?Q?s1+XBk0MS4k67M07RamFOG98ZNL4T/mccAt7GmA5nEX/fzckF+TYPA2Xr/ug?= =?us-ascii?Q?hG9064SGi1by5hTm3S9ULD6U4vPsJfiA3rxB2amfVU5zTg2dUWU+GeZUghMP?= =?us-ascii?Q?llJN4Lcob7rCmpHuIfbi0QoNyo1riMuLfNXOYH1XWhYxTGZQ0l5D/oHHlWWI?= =?us-ascii?Q?WMNAi2zvC7tHE0LyWQnbsqw7foAxMtDJcsB3DsKD5NGnC0mdf2nsW7ZAa/Wy?= =?us-ascii?Q?1mChDEzLnMob2/1WZvplNVbj2G8zOVl87UPhAPVuKzAVFPOtfvZg2uI/l/Dk?= =?us-ascii?Q?wgT3uAe6aBiS8V8RSl+Pfotfz2PCnp7tbXZvZSrpdqmdI8Un4BNHHpSHtOpB?= =?us-ascii?Q?BxP2ePa1rZBgQgGK1/WsCaqXptJKn7QRZTZe71/kmh/qMdgHi6SZrwSSvrhN?= =?us-ascii?Q?71swJzDVNZddNTamWbcUmJdtgCaD7lHrEu1NNEtdVXLsykmvzLe7SMAfe842?= =?us-ascii?Q?N+JP0RXzo53BuNUm59SG5vZ3DH5cr6pmiAHk7dI1mbzZMKWZlaAni0rVYJ3o?= =?us-ascii?Q?eOWOYJVRTCX1exZdzvCZcZqdxfn+au2mR7jeP8vx8zDtr8WcRkejp0Bi1wyg?= =?us-ascii?Q?RwXvOtaVTFMc1YkRgQqYSoIOG0oISNOkKVWLqEzD9IU2g5xN/WRONaBk3c56?= =?us-ascii?Q?Btl1z2cVAiuyUiXBOU5UhrLSG5Iac8TgwsPEwNJJzdLOBkvvH94gebWspfSn?= =?us-ascii?Q?fPqolXYPCm38glTOYYVCQ5OFaTyW1ubmSrJEs9TOX+vE7WZz9pegOckylh0D?= =?us-ascii?Q?t8U3ZjePwq/MmcnHexOCd4LA5WSRm2gY3nLuyB4RnqOGLCDuJIf7ThY3Qrr7?= =?us-ascii?Q?AMcYA4BdThNKs8ITAonSdLD1O+fuPZN9/6kEIWnTUJaiU1xtlIT30q7G89hU?= =?us-ascii?Q?dS+h0HcWx954/BOeXo5RQr1+EyMfaXR0y+LbgjAZeVVMz18fm5Ra5gk4eZPp?= =?us-ascii?Q?Jo5hyqBTKQ8Hyj5N1kJ/ycN4anhtyZvRBPopGtiIy1ZvVRFS6fVsFJrWfMOO?= =?us-ascii?Q?8OgZfxF+7WJJBfRVlOov9nq3GAVfsi9/rLyZie2i?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6a7fc523-01f4-4549-ebd2-08da8b6582b8 X-MS-Exchange-CrossTenant-AuthSource: CH2PR12MB4181.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Aug 2022 15:28:52.9314 (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: 2YYq0DfsTVMUnBYosp1MtY1SHg9VpJzLUzSxIZayXDpjMGBe2m087F0TbGV9CtJQ X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB6385 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Aug 31, 2022 at 08:48:55AM +0000, Tian, Kevin wrote: > > From: Jason Gunthorpe > > Sent: Wednesday, August 31, 2022 9:02 AM > > #ifdef CONFIG_VFIO_NOIOMMU > > -static bool noiommu __read_mostly; > > +static bool vfio_noiommu __read_mostly; > > module_param_named(enable_unsafe_noiommu_mode, > > - noiommu, bool, S_IRUGO | S_IWUSR); > > + vfio_noiommu, bool, S_IRUGO | S_IWUSR); > > MODULE_PARM_DESC(enable_unsafe_noiommu_mode, "Enable UNSAFE, > > no-IOMMU mode. This mode provides no device isolation, no DMA > > translation, no host kernel protection, cannot be used for device assignment > > to virtual machines, requires RAWIO permissions, and will taint the kernel. If > > you do not know what this is for, step away. (default: false)"); > > +#else > > +enum { vfio_noiommu = false }; > > #endif > > what is the benefit of enum here? It means we don't have to use #ifdef to protect references to vfio_noiommu. Do mean enum vs #define? I prefer generally prefer enums as they behave more like a variable. Jason