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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?M6Sa5ivnL7Iv123yk2mm5nhz2xtiLxZtTzdC1B9JdCNdGquC9+cQIst2ZRhN?= =?us-ascii?Q?YyPWLTkjgdgPUbaMvr7pQVi8LVdBuEM2tSI5hyQfQfrmOlmetbHqpd3hAYdp?= =?us-ascii?Q?MSdUfhNN+RIWO8mrI5PztMFGiWmenvaj6C+3+vRkKlgJrxMAc1qoHkm0NPIY?= =?us-ascii?Q?34l0Evkentrns05EKojabmHiStqLzWKkaCW10fcClajtDPDzxtV8bE5XWDsW?= =?us-ascii?Q?VNtj2moLbq4r4UOTGH5XJOjEboF6sbY0HRvmLuXKfJMIp5g2lhwciW3gf6Q4?= =?us-ascii?Q?XuT3gJ7k0U6c+cDJCjc9uMbRElnPDz94qCm5/QYmET/HejjrxkXjXYUNpIb0?= =?us-ascii?Q?9/QKjJ2YZjUxaCW7Xa8+Z/M/E3Ydn/jx6vo8H7LOzU9DRCJ49/hHh/iXd5Qs?= =?us-ascii?Q?DWIgpBkgKeJTf20BhGEWvXsfWV46GnkiRfk2ciMTzwAeCu2EquH//UB5fxcf?= =?us-ascii?Q?BnpMffYItBi/e3U2ZoBeLpjoTkOUIsFJHIJ4un6qu0Z5tQe1SzJPnrcvd0LI?= =?us-ascii?Q?QwNQAYOAqTB1rlg1GjxQ9F90LmIXzYjTkwfH37muauOeTqBure2f1Sq91xJq?= =?us-ascii?Q?5iCmrHU1yb5VvQ15A5Np6hi8vJThBpCEGS0Ru+7HnQ3aiABQDp2N6cbA6xxH?= =?us-ascii?Q?ZM39LI05PSojE+D/32DJfJDxO18V4DeH+3BMBgGMtNKT8yhsLDvkO8oM0FQO?= =?us-ascii?Q?kKpx4u6pFZ+UhQkBYqF661Et6O4KFmt1IoX3EgYbRYnPnEq4xPwMBzEB+BtM?= =?us-ascii?Q?ndVJB9RJtvQEZkuIbOnpoaxmWwDHDCB7W2dYSWXnjrwrVfyYEGd5wHfpHxyI?= =?us-ascii?Q?9oGsge7PsgLBHTANuK5/bFjtDzg+/33K2QvtF+0tDYtP+LB/k11baRPYy4Gf?= =?us-ascii?Q?InGfhm4lzGX/oyoM4NrES9ox1Qc1dglHBb1LN/aHAPO5OpIC1llXWFC0UaJt?= =?us-ascii?Q?a6HSs0HuWAojp7s2cpH+OLuhDtwJ4CI/cRkPvnMpvhnp3MPMT7aZ+MIjk6Mk?= =?us-ascii?Q?Xj7KoqrtsfvHgimYw+svrhIfVw/hlLL6P5NhheMOzq7O57Ev9eYNaolN1tBu?= =?us-ascii?Q?hxJwlwBOqPik6dLlndlvN+3rI1sfXGytBLemwxsVEnKXbao9hO2nr+xsTjit?= =?us-ascii?Q?2axCOC+28pwL4HaisREcYmGLv0OmLAYahC4TrRDsEkSgzi18unSAcZPCC1kG?= =?us-ascii?Q?TG8w/Qt8GBoKJzjoqB1NMVu9RBaNjD6HVkmNPperti+GJ4K44UMEtb9/sgng?= =?us-ascii?Q?65CwDRchQzEvXMkl1JtHAMe9BeDFQccOpG3S0ct/81y+ok0kAYSpmjvx5B/1?= =?us-ascii?Q?RVNv5IRpaow1F4ZQtgjliO606I6AJUkhJVD22nq+og3FkVR5vmLSFPvCNzSq?= =?us-ascii?Q?X+fKcmG6IR94k0gDevcm1K4vnJzFQM0Ejh9UWBHDG5FqzOhrI6Xw8vbaSJ7I?= =?us-ascii?Q?43PH3x2NX9jkuM5iEGN9/H8UtpUCz0+kTunqHuBaeCAoFX55guPXg7g+LnQg?= =?us-ascii?Q?xH+102m5MunYM/8fUHGUq4ccrHjemeKYboKXlrtWoPQAT3AdK+MtfD0aEXtf?= =?us-ascii?Q?vk6KjJxFdZmcRDiBa+8eARzzCIlmGu56yzjxbHMhCmqKgK/8CQEzvf3qeu50?= =?us-ascii?Q?YYwtHuor2v0NmT7HcVpWBTo=3D?= X-OriginatorOrg: os.amperecomputing.com X-MS-Exchange-CrossTenant-Network-Message-Id: 19bee514-562c-4e41-ab4f-08dc58317a88 X-MS-Exchange-CrossTenant-AuthSource: BL0PR01MB4226.prod.exchangelabs.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Apr 2024 01:07:51.3313 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: qmo4co6KoHH9ztIy+f0VixdnvJkUKFR7l506a3SHlIDPP5Fsvk5C6X+e1BIaFk5fA2mMUMhUEgH7Pl5AvIhEiwcMgSypZMFAQQLVCiWDFnv1BiBLksUuM1XpXGFBGGNN X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL3PR01MB7097 On Mon, 8 Apr 2024, Robin Murphy wrote: > On 2024-04-05 11:33 pm, Ilkka Koskinen wrote: >> >> On Fri, 5 Apr 2024, Robin Murphy wrote: >>> On 2024-03-07 7:31 pm, Ilkka Koskinen wrote: >>>> The driver enabled and disabled interrupts even if no interrupt was >>>> assigned to the device. >>> >>> Why's that a concern - if the interrupt isn't routed anywhere, surely it >>> makes no difference what happens at the source end? >> >> The issue is that we have two PMUs attached to the same interrupt line. >> Unfortunately, I just don't seem to find time to add support for shared >> interrupts to the cspmu driver. Meanwhile, I assigned the interrupt to one >> of the PMUs while the other one has zero in the APMT table. > > I suspected something like that ;) > >> Without the patch, I can trigger "ghost interrupt" in the latter PMU. > > An occasional spurious interrupt should be no big deal. If it ends up as a > screaming spurious interrupt because we never handle the overflow condition > on the "other" PMU, then what matters most is that we never handle the > overflow, thus the "other" PMU is still useless since you can't assume the > user is going to read it frequently enough to avoid losing information and > getting nonsense counts back. So this hack really isn't a viable solution for > anything. IIRC, what happens is that kernel will disable the interrupt eventually due to unhandled spurious interrupts making the "working" PMU also useless. Cheers, Ilkka > > Thanks, > Robin. >