Map made every singly mapped section page private resident memory. A JIT
or shm_open section is file backed and committed: its bytes live in the
file, and its alias descriptors map duplicated handles, which the physical
page slots do not match, so a resident copy diverged from the file, and
committing its view on a demote failed with access denied
(guest_jit_shared_memory). Only direct memory backings, mapped through the
new GuestArenaMapDirect, now become resident; other sections keep main's
shared views. Shared pages are committed only while their section page is
reserved, as on main.
The socket host write tests map their direct memory a second time, so the
write-protected shared path they check is still the one they exercise.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V1W4jdNSKTV7xwuS6xQPJV
71da166a18