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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?DsiAhTHXLrS4gKAAw5OMGD9HqvVhqm9ylwZcb7sxpvWmWs594XdXQY7HEQuU?= =?us-ascii?Q?5xlE4EifjE1vELrEuoQAfJa2+qtvgvF4dZCQoCJsG14hJsCWd4H5b+37u99M?= =?us-ascii?Q?+T9MuXcp8ctVK2TXJIbKxoAVMOTLAyShOL4Od+V9VwBlGDj1FYhX3RKBlOva?= =?us-ascii?Q?8iMwBa/dBax8T9S01KEXXRLZeQAboFZ6zg6x3crVN+6U5yXd5lvBIEBBj1WH?= =?us-ascii?Q?pOZ0nbDcJzv3ShCsBYPB43DbsrUODLvwT5qZA8Gfd0PgUpnY7Acyn60oy/1C?= =?us-ascii?Q?jCpdoYRHZMY4Q0f29M/MHwNa5Zu9xXAhqePtA3xeJDDMZtH4xagjAA0gU8c+?= =?us-ascii?Q?AGzPtM+okpeqUyg7R5kXvfNVk0+zP56FPLpJiDjoY7IS6h0CqJ9V1M5OP/J1?= =?us-ascii?Q?bGmC6dQ7HoZBWZsHudtVuI4UJbJuKpBvEhKypIvVTVmDHTlkygVCaE8MTAlM?= =?us-ascii?Q?NXMm1IaRNWBaP8zknnRuhvnRu3GBWliexJFIUeveZZ+qsFOPMiK8f5Amhjs6?= =?us-ascii?Q?h3+C/Wpkpv44PraB1A3EjePSovyAuRPNDDq/wjRcoAfuV91+U893jDlmRM5Q?= =?us-ascii?Q?X73xEbOddCp1UZd/TOfhNJLRsYl7H3PJAllcc596ussGWPFg1ueeir4F7z8n?= =?us-ascii?Q?Dfu5S8sKQw8Qi/MWoGoo/Jy1yHUwH5I/Ij9Bg/VhxYePuOJdRnIPgJob39Kq?= =?us-ascii?Q?acbRugp9PpGed+HHS1KnGuGgO8q4wB2CYpeie3LZ1xEjA3fbhcuy/i6R3wEr?= =?us-ascii?Q?1h8gGNXes7QnWha/ekguk9I0adw592FuEm+O7nzgTwFyOviYHph/OuAdSrQQ?= =?us-ascii?Q?ge5JdLEQyozX3e+juCJR/ucH+qnGNi4UmFIu3lkiwHVOlZ9r8jyaXioKEgXW?= =?us-ascii?Q?R29LsuAa6a4qcL24TUnZHGTaXELkeZaRJ0h65hhrWmt+sZBiC2Z/5n5Yi/6i?= =?us-ascii?Q?XPuAj4iNH2W7zsBBO5ABvhvSn4IOSZ+/QIygMYVA8kNBHyYW3xm6dcqbMceX?= =?us-ascii?Q?748QiYg1V56NFVmgyAiu6fpXTlgZnQOoS6vMvCVhAFKKljd2iZTwlBKLBhLh?= =?us-ascii?Q?qvRCFTZbOizHyp4oLzJKPwmXjLj7FWVMPSSvVyGpxFOB/D7+brfPO2RjJ7p7?= =?us-ascii?Q?pTYg1Lv4lGyR84OPIkxi/7QHy/JqiNFB8kVd3Qg6V93aMcOg8rSiORCQQYvQ?= =?us-ascii?Q?gMB91cwWKvd/mx3ObZ9f5zJsKVYm8R6idiNoqMztDVWU5FwMIzN8UKsTkF74?= =?us-ascii?Q?cvAxOD/pfnkhix2Z2TL5xh1VDB9MJgZuP7cIqgx2qwmv48wN3oIIs2NpD2zr?= =?us-ascii?Q?4cVgpb4vIBPjye3JUgEXK7yp7E9neetUr7dBMO0DSAvEaI8GvytvQEM9E3tm?= =?us-ascii?Q?F99FsfpPfSYCm0XiyAnbc2+qwM/8EFEZoQWERroGo/jBCTTaO9sqiaQOumaA?= =?us-ascii?Q?a0emuIuFOT3zavW7XPNEIgww0cMxsoQbH5BIHDU9TiuLYSh7nsniFVvCQvV3?= =?us-ascii?Q?Jl7EhQG87bE3a/x7Jiaud1trU7KfHYxFzex+gBljUkYl3eah4FVYSLV6nvVp?= =?us-ascii?Q?lhXyRTPJbIqXW8mFgkwInnS+gXo5XHXmoUMB6WtCtwFq2hFM+et4kpZJkBco?= =?us-ascii?Q?bShDkXC6ANNUbQ4BElUvmK4=3D?= X-OriginatorOrg: vpitech.com X-MS-Exchange-CrossTenant-Network-Message-Id: 29f2b6b1-d141-4a3a-6b65-08d9c3dfe800 X-MS-Exchange-CrossTenant-AuthSource: MW2PR07MB3980.namprd07.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Dec 2021 17:41:09.0538 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 130d6264-38b7-4474-a9bf-511ff1224fac X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Zx5kKAeeXdBLXZQ+l5Hpy06T/u/frdeWQ/CcoToRN4gO+hhJBdjewhk/e2pFddo9I9btSxawxoqdZsqfNdEaCQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR07MB8668 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On Sat, 18 Dec 2021 12:39:11 +0900 Hector Martin wrote: > On 18/12/2021 11.51, Alex Henrie wrote: > > On Fri, 17 Dec 2021 16:41:05 +0900 > > Hector Martin wrote: > > > >> On 17/12/2021 09.31, Alex Henrie wrote: > >>> I am having a similar problem, but unfortunately this patch doesn't > >>> work for me (I get the error "BIOS uses SMBus unsafely"). Would it be > >>> acceptable to add a module parameter to allow access to the SMBus, even > >>> if the BIOS is using it? I realize that this is not a good idea in > >>> general, but I believe it is safe in my particular case, and I don't > >>> see any other way to solve my problem. > >> > >> How is this safe in your case? If the BIOS is using SMBus without > >> locking it, and may do so at any time, then there's no way to safely use > >> it from Linux. > > > > The BIOS appears to access the SMBus during the first few minutes after > > boot, and then it stops using it. So "safe" may not be the right word, > > but in my case, it seems to work OK to use the SMBus as long as the > > uptime is greater than a few minutes. > > Linux will probe the SMBus on startup, so that still seems like a rather > fragile situation. You'd have to blacklist the module and load it > separately a few minutes after boot, or something like that... It's awful, I agree. I was just hoping to find a slightly less awful solution than patching the kernel to remove the BIOS access check, which is what I currently have to do. It seems to me that if multiple people are in this situation, it might make sense to add a module parameter to disable the check. -Alex