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Why? This adds "security" with >> _basically_ no extra runtime cost. The runtime cost is, what, usually >> one kernel TLB invalidation during boot? > Plus potentially a bit more TLB pressure from losing a huge PUD in the > linear map, IDK how much we care about that. This shouldn't be a big issue on ARM64. The most ARM64 machines have linear mapping mapped with PTE if rodata is on. Some machines with BBML2_NOABORT support have linear mapping mapped with PUD/PMD, but those machines typically have large memory, having 512 PMDs instead of 1 PUD shouldn't be a noticeable issue IMHO. Thanks, Yang