dev devices with permissive boot: disable perf_event_paranoid
Some functionality based on eBPF attached to tracepoints (gpu memory accounting and time-in-state) rely on newer devices running with "disabled" perf_event_paranoid controls as a result of the kernel having LSM hooks in the perf_event_open syscall instead. This is tested for, and set up by init via the sys.init.perf_lsm_hooks sysprop. Development devices that boot into permissive mode still want the eBPF-based functionality to work, but end up with a paranoid value that disallows the syscall, as the LSM hook test expects to observe a SELinux denial (which doesn't happen due to permissiveness). As a pragmatic way of achieving the paranoid value override, we pretend that the hook test has succeeded if we detect permissive SELinux during second-stage init. It'd be nicer if we had a sysprop to reflect the device's on-boot status of SELinux, but it's not worth adding for this case. BYPASS_INCLUSIVE_LANGUAGE_REASON=technical term Bug: 170674916 Tested: booted crosshatch-userdebug with permissive kernel cmdline, confirmed that the log message from the new codepath was present in logcat, sysprop is 1, and paranoid is -1. Change-Id: I9df5da2076cdbd777d35e50e8cd7a483ec85e20a
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