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Description of problem: It became apparent a while back that the kernel should be enabling BTI for the segments it maps rather than relying on the dynamic linker to perform that task. Otherwise secomp as used by things like systemd might attempt to block changes to executable page states. The current RHEL9 builds are carrying a glibc that will attempt to remap rather than change protection flags, but this doesn't work for the main .exe pages. Meaning that system services marked MemoryDenyWriteExecute=Yes (MDWE) were running without BTI protection. This series: https://patchwork.kernel.org/project/linux-arm-kernel/list/?series=494119  attempts to correct that and should me merged once it is ready.


Version-Release number of selected component (if applicable): RHEL9


How reproducible: 100%

Steps to Reproduce:
1. Convert BTI's to NOP's in MDWE protected services
2. Note they continue to run, when they should be failing.


Additional info:
I tested the listed set, and its not working right yet, so its possible a newer set will be posted (or I messed something up).

Jeremy, I can't see any resolution to this upstream yet. Reopen when it is worked out upstream.

There is movement with the https://lore.kernel.org/lkml/20221026150457.36957-1-joey.gouly@arm.com/ set.

Although, its not yet worked out...