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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 8SBnZLBovMkn/8ejtC1xTHA0V6KceAmsxLb+J+DKcwF1m8m/qzO4j6jZXkfZU0iO3LXrQ6pdIgbhcluOzbjcw3Y7iTh47/01+FxknKGVmT+vBCHROQOBQUnv22NuVaN0jelNYyohfV9c3oR2NRG36liOaZCSFDELOJqqc7MIO9oGSYQIpV9SwtCpZKfqgzSJ3TjYJ1a6K1IX+CWKC5Mplh8MVMmE9U9WBOK74Sy7TxAtVfExrUprZqyzD0p0ndyvTyY+z+bvGr4K5yYDR/9g1Ung95lf0Ym4oBR57M3w1orbwAAz4Vu8toqdy1yQSIYpk2GvwCvXZGMKQZOyKu05JS4Bh9xfMvJrTB5KATvRhFfzWCRsUAO1dq8Clml+tAPqI8/xOvsX6VrFY+174g/N66ppo3QfcqDMeY+QZYjRRtk4lu4PbhzKQ7fKBSE3gJxD X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jul 2026 13:50:38.4034 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 629d9904-16c7-4dcb-4687-08dee665e1a6 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[4.158.2.129];Helo=[outbound-uk1.az.dlp.m.darktrace.com] X-MS-Exchange-CrossTenant-AuthSource: AMS0EPF000001B3.eurprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MRWPR08MB11758 On 17/07/2026 3:53 pm, David Hildenbrand (Arm) wrote: > On 7/17/26 14:32, Alexander Gordeev wrote: >> Hi All! >> >> This RFC is a result the implementation of lazy MMU mode on s390 [1]. >> >> Heiko Carstens requested some mechanism that would rule out direct >> dereferencing of PTE pointers, which otherwise would bypass the per- >> cpu cache on s390 and lead to catastrophic results. This is the exact point we want to fix once and for all. Please feel free to review and endorse the approach we are going with on the original discussion. > There is some information here: > > https://lore.kernel.org/r/6110202c-057b-4701-8c04-1a76ee7bb9ab@arm.com -- Thanks, Usama