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Only set delayed inval for procs using PTI
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Authored by vangyzen on Mar 5 2021, 4:43 PM.

Details

Summary

invltlb_invpcid_pti_handler() was requesting delayed TLB invalidation
even for processes that aren't using PTI. With an out-of-tree
change to avoid PTI for non-jailed root processes, this caused an
assertion failure in pmap_activate_sw_pcid_pti() when context-switching
between PTI and non-PTI processes.

Sponsored by: Dell EMC Isilon

Test Plan

With that out-of-tree change, systems using PTI always panic during boot,
soon after the first non-root process is started. With the fix, they boot.

Diff Detail

Repository
R10 FreeBSD src repository
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.