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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?247wiHT0eRQvaIoRAcM7N9Gn6nwC429D/fuXXZfIJJTM4ynzd4xHOpiIUBDe?= =?us-ascii?Q?rAJXPnw0EijoVEEfR20SEv6KQbSw8dYlqhhtSD2dckEgJT1w1o6ZYaHZD794?= =?us-ascii?Q?k+Zoi14NgwCTyJ12GEPPsWESWOtFrVH6nCPSjpB51BxgmwyyUx8T6LnlBSM+?= =?us-ascii?Q?B9DF7Kc971wVPgA5cjX9xKty6w3WVAH52GXVwd3TeqJTbMAbe8y8dKzct0IV?= =?us-ascii?Q?cXpRsrlps6hxXhArExYwaES/R+OjSFhMRuAoJNT97jD5RP64FtasPwzyxdiL?= =?us-ascii?Q?WsvnQsAqBifTwZnR9Py3AgLYKei2pX9HEvIZ8nUtcZNYB3nSEVa8UI7MLnRJ?= =?us-ascii?Q?Lb7PUWoCR/8CIKTJqgWcUqqRGhXN713uvf6C/bMbX//8FVQ285Ce0ZCEnhfM?= =?us-ascii?Q?iG7/uyHXVIIWEDDbLaCisNnXX/nf6/hQgT8akpVo+oBn2tlPxrwLeUoqsZ55?= =?us-ascii?Q?zCtcL4DukP8Eh768KfV9YwUDmMU7uy8yCJDZlu0jF172zb0tSGPOYO8lDkV6?= =?us-ascii?Q?+mlaNDAr0pE2Td5zir+Ihlnn3TKVtudnKXtTkh2SB0g5zti3C5XvNFPt7Kz7?= =?us-ascii?Q?4MCDttYWk6YlXuYBASLPMt3ZmE8ENNbqEJ8k02U7IK9wZ8b5gONZpI1KBKlb?= =?us-ascii?Q?7wfxrtILh2JrKiQqrGF1VcbwiInU/lWqWQkiBWywLAVJZg+yvVr6QwrqFbMK?= =?us-ascii?Q?Vu2QJCNS9WOqM4yUyRShsuaV1eoWb5wktYT+SvJSNTdD2bU6aWRRTrsQ0aEO?= =?us-ascii?Q?2kXCCScP7xOi+4qMdkbbchzev0bh9JNrKYhDNdetE/uSIojjnCT90d76WTQy?= =?us-ascii?Q?zzBozpuClMwiRR/ISs0S7byHMgZL/HDl1a3yiTS6ohq2Y7JvMGXEzvMh95Cb?= =?us-ascii?Q?P68AtA464d8DjefuW8zLysKrZ1uSDkiWCCuyn3H51J9c6kMjFR3Pqbp56Pqe?= =?us-ascii?Q?qzxngab4WUjgJvkhiVN9sBnR34FFlnbh467Ww1kyJoOdNXhc3qBW+uZhDfAp?= =?us-ascii?Q?O2U36JxhgNuhwRWS9v6vYkM4hArsg3qhM4+OvGPlxhEGoewl1RAoTs3jkKNL?= =?us-ascii?Q?eggw7EZ2zGc52tiEKWCof2pg3VJ1bsaX1axPHTP/ycbbm9+g/t28Gym7IV9s?= =?us-ascii?Q?puiKl7aqsLGmw8RWRsB9/vyyqpziI7YScoV5Q+5y8AxEh/sUYxieIbEw1Ou6?= =?us-ascii?Q?8ud8Vsd0Rduakvf0Np1cikALjl+pFLN8zbUszjV0CIF8c/1ohvXJ3exs0xXE?= =?us-ascii?Q?kgivov6uEpp+ANkadcyUOFimlVoh62uyhr6ieIiqfa4/1E3vhT/qRpTi5EQE?= =?us-ascii?Q?pJ9buF2DeETXqdINoEVvg+SiCLYSotv+62Ky4f1GVxHxBJ2E35Oid7njSggl?= =?us-ascii?Q?sa0gfqKrDa7/wI/++xxbgfvS0bBmJorTU7ISvkF1wRBqlPJQrfKkhpdyXBmL?= =?us-ascii?Q?gSGg5kbdTqKcm7cf7A1jS2+tthrHtBLHlCzO6Ef1kzDR/cW24NOjyEmwW6zL?= =?us-ascii?Q?4hhPoZ3/dptfHZb4BSlsXPb0Rf59eX2YvCF7oLRUBiytDfCxKyZu7xtEsCWm?= =?us-ascii?Q?1lAWPh3+pZX5tIgIRs1gK6l8og/ZfeMKE8zdZLVI9ozpbfp30Z97lcEPc61H?= =?us-ascii?Q?epWA5c5r5LlkNk+dBefMd3I=3D?= X-OriginatorOrg: os.amperecomputing.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5935b2d9-aa77-4ea3-4b53-08de25fd2a2b X-MS-Exchange-CrossTenant-AuthSource: LV2PR01MB7792.prod.exchangelabs.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Nov 2025 17:17:20.0767 (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: XDjBv+rWoUjzHO6yHMn3CDACmkfYA1zOFo5nB/QHHsdF1hC+LlW+nN1zAnw6H3s1POnfb/dwqk/5OfhyAdKitokBlgIOP5dnLIihtpxzsPrNJZkMrh/phZ2R40IPTXyl X-MS-Exchange-Transport-CrossTenantHeadersStamped: CYYPR01MB8262 Jaikiran Pai writes: > Hello Scott, > > On 14/05/25 12:15 am, D Scott Phillips wrote: >> On AmpereOne AC04, updates to HCR_EL2 can rarely corrupt simultaneous >> translations for data addresses initiated by load/store instructions. >> Only instruction initiated translations are vulnerable, not translations >> from prefetches for example. A DSB before the store to HCR_EL2 is >> sufficient to prevent older instructions from hitting the window for >> corruption, and an ISB after is sufficient to prevent younger >> instructions from hitting the window for corruption. > > I see that this patch enables the workaround only for AmpereOne AC04 > systems. Do you happen to know if the underlying issue for which this > patch was introduced, impacts (or can impact) AmpereOne AC03 systems too: Hi Jaikiran, this issue impacts ac04 only, it is not present on ac03.