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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: AigD6oTlmhnycoopB7RWJ9KWIu49ijACoS5FM1sgUu1zzAnOjlMnnCS0l+BjofA6htmIXl+wTafXEdskwGGxnoFnvm6yat3fp9EczOCTAREF5DMXL4XeqIo7plJ39AeFXuONLziNBZXueq75FoJsHGZIwjhdRPkgNxDKK4DVR9YJCdhYTZTF+EBOH5fXZRH+o4uL/lY+JqRO+VT9wnkUzTvSJT14JRWn6K47WAUjwRfuVeI7AV3Qi7t/mTugmvtGmWJzYRpbj8pwgBpAR4cNZCpJndkx1r1lnnSbXojdCiNYFziN254CgZ2ZIwrax1RJ8u/T+un/h8RNq1Sqxu1aajCUIc9UaV6fNwMm5UukGpV1QBBDz0mMDDgskO2GQOND5yzCdZhPw7ICKPnfbHn+UvlDrC0BdLG1YZ/4pdHvtqPEp9d2fV4QD8ayzmPK7Eao X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jul 2026 11:11:31.1447 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: ad8d3397-a4a0-4483-ef70-08ded82aab91 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BL6PEPF0001AB4B.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB8193 >>>> permission under SELinux (things like JIT or regex compilation need it >>>> as well). mmap() with MAP_ANONYMOUS will give us a zeroed mapping that >>>> begins on a page boundary, so the result is equivalent to the original >>>> code even without a memset() or the page-alignment dance. >>> >>> I would argue that having RWX is a problem, you really want RW->RO->RX >>> transitions, so even with mmap() you want to combine with mprotect(). >> >> My original intent for using RWX was to generate sufficient Icache miss >> samples for the IBS Fetch unit by overwriting the code prior to execution. >> I am wondering whether it would be possible to achieve the same result >> by using CLFLUSH with RX permissions. Something like below (build tested >> only). > > So for a test it is fine to have RWX Sure, makes sense. Thanks, Ravi