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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?O3gmKb4i9ISBb+suydat9RD3VFyAZ5rBdXYocy7H70tg3yNkAwDullCJAB4q?= =?us-ascii?Q?Rk03DUAwayilIG7kBxKVSsxVbon4ESN+OMixWQoqqlN8HNUQpVH/UYfRPAgC?= =?us-ascii?Q?/PIEplPFrqdhLg3RdYRF8fo6ITFvoc5zRwp/xieLhuBBzy/yoMoTCYnrmI9C?= =?us-ascii?Q?0Ur1wCyh4etblIUD/d8Yhh0UZZd6ftwHW8fvYIB8jJ+L/s/SROQ9iJkrd0yX?= =?us-ascii?Q?FXYIb7sy0E5zNokMLaTptdMI9MICNdUFIyU2rTav+jkDTSCxwkVWLgf0Ziny?= =?us-ascii?Q?+ffkGW6EFtjQ8WR2bHngk3Ep45Y4M5iltJaBhg4z989xyo/Zg/brpxa3sl5a?= =?us-ascii?Q?7N5LpNxzcm1OiCMCwb4WJD/3bfQG6BZ0kTXkEUTwa5RI+QNCeT09vUKN+W8y?= =?us-ascii?Q?YZUv1ILzyULlM/muMnmJJBjX146ry4MEbEQRKqAnyHnpb9G7OEJxPb/1Y1qu?= =?us-ascii?Q?zZUs3u1Bnsvcwh97YjzhiEDKM3nHCYdSJCJXFBkuGQm6cshcQvhd7qa2ewyR?= =?us-ascii?Q?ZdzywGlRRGf3LBQwsbZfP1HQfNCxxmTAeYyleYJFY5mz4X9Nx7ExMP0x+W/W?= =?us-ascii?Q?B8nXrVGzoI32S/Dhc7zLpYYogDjW2CYXe6Jha+n9Xmm8Dxxsza7mJgv0kt4/?= =?us-ascii?Q?URRsgDJNaFvC8bLMBjpbG2voLRjSrKv+JzGPdJCDXeCBccyB3RlxWl9iF9WL?= =?us-ascii?Q?xxxrdjMWI3909wF6Zpu7XyZcFgJVINsx21BLwNuTzRS/d11hLTeiUjc68g4l?= =?us-ascii?Q?aWHqCRt4EUv00+Ird42lyHEOsACHctqbkCteNcpANZiK5/LvDJhFI95kMhp2?= =?us-ascii?Q?8bBvzPt5nwOx9gCSEdZvFC9Fqp3KZyBnWmZevJUkt7V6Zlk7PIKlPApzD9dy?= =?us-ascii?Q?X27mz908c8RGQdMXUCyWY5AnzVKz9aVVNjA42MTLM+R+nqMLNbO8QSYkox/u?= =?us-ascii?Q?Lwl5LfeW21zisr10yY4JEOILi0lxczNkf63xQ+qPHxDlYodnxFfkuvPG1/NM?= =?us-ascii?Q?t37ScNFReSMRuYufKmKCvvsTe9AgWg4SB7gYWnWkXe0d+gsu0xmF225z2Gw9?= =?us-ascii?Q?sAHubcgMQKOhG5w22fnN+eDvPuwvg+hrLrPxbZ9LDlZR2EnMSUmk+AHTP0Be?= =?us-ascii?Q?gDtsmzf35skBoJ8//Mc+DLYubTNDVUaiQcfgWKl7CIa+gYyVt/teHRqSi+V4?= =?us-ascii?Q?/hB380Jt19Napyzo/esY6u5WeJCgx403uMGyFBTiMx3JtTjfRXj7GfCYIVt4?= =?us-ascii?Q?SU60KDv2I4UBeYvknClrj0hcOH+2EW/vQiu10ZAGurLGRW30J/Jc7YQfCJ6O?= =?us-ascii?Q?qJtpmXO2sKykVBiG0i8Yj78hBDwXS1ncBce7zGSB6TeTO5bIVoD8EaIepMqA?= =?us-ascii?Q?YK2P8uVn4KjClSxi3n1VO0uFg1s0/yk1UT0WRjq2gRjyz9ghwGOHDdQeAG1/?= =?us-ascii?Q?Wyk0hZr8DN9iN8FvztNzkIDrJWgLJrOTqkWE1DCo1pXgVechiUjQO0wJYNPv?= =?us-ascii?Q?58TGyHQqXANBdfPTaRwLJLhZVmLLJC/KIc5Q5PYfFExweHYkV9/Vmb415jAu?= =?us-ascii?Q?A0hvsCdUB9OJuPFnOBfqD5vwj0Pd7DBsw1OqAJ+jm8mJbaMN3rexhqGtM192?= =?us-ascii?Q?MG2y0Kit+o+5MYT7R/R8zE0=3D?= X-OriginatorOrg: os.amperecomputing.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0dcd29c8-8537-4fd3-7a86-08db6cfafb15 X-MS-Exchange-CrossTenant-AuthSource: MWHPR0101MB2893.prod.exchangelabs.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Jun 2023 17:15:41.4462 (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: d08IoWWU28diCR9rfnvG/pgQv2hFMrHEeD3nHSIAPjXfQ+aa2y3ywZi19lYzhKIBzgn69TSOMpkMJ0AA69oPTit/z5wCl+dxPiMnMGXZ+q8rGhzXiFsUvtLghbVsY9p1 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR01MB7781 Oliver Upton writes: > AmpereOne has an erratum in its implementation of FEAT_HAFDBS that > required disabling the feature on the design. This was done by reporting > the feature as not implemented in the ID register, although the > corresponding control bits were not actually RES0. This does not align > well with the requirements of the architecture, which mandates these > bits be RES0 if HAFDBS isn't implemented. > > The kernel's use of stage-1 is unaffected, as the HA and HD bits are > only set if HAFDBS is detected in the ID register. KVM, on the other > hand, relies on the RES0 behavior at stage-2 to use the same value for > VTCR_EL2 on any cpu in the system. Mitigate the non-RES0 behavior by > leaving VTCR_EL2.HA clear on affected systems. > > Cc: stable@vger.kernel.org > Cc: D Scott Phillips > Cc: Darren Hart > Signed-off-by: Oliver Upton Acked-by: D Scott Phillips