vgsp-gr: B-2 planted 64 MiB data-bounce region for large GR operands

Replace the 205-page / 68-pages-per-pointer GR operand window with a
boot-planted 16384-page (64 MiB) region at VA 0x0a000000 (PD0 80..111):
one dual PD0 entry per 2 MB window backed by one fresh 4 KB PT page,
every leaf PTE written at stage 3 before any engine fetch (the GMMU has
no PTE invalidate, so no leaf is rewritten at runtime). The 208-page
window, mail slot 206 and marker 207 stay as-is (mail injection and
copy diagnostics unchanged) but carry no operand data when the grown
region is on.

Sema service: reloc base and page cap derive from the shared header
constants; per-pointer span becomes a 4096-page runaway guard; a total
cap hit is fail-closed (launch stalled for the bounded hold, loud
CAP-HIT log, no silent truncation); the launch's own param/bank pages
are skipped as data candidates (budget hygiene). Copy-in, copy-out,
retirement wait and the window diagnostic index the active region
through one helper/chunk selector; checksum and dedup scratch move off
the kernel stack.

gsp_phys_gr_data_region=0 (insmod, boot-fixed) flips the whole path
back to the legacy 205-page window for A/B trialing.

0 files changed, 0 insertions, 0 deletions