On Linux the write watch protects pages, so a write-back from shadow storage into guest memory took a fault
at the first store into every page. plat_mem_prepare_write clears the protection of a range with one
UFFDIO_WRITEPROTECT call; the pages count as written, as they would after the faults. Off by default;
Windows has nothing to clear.
Pull request #327 by theurbanninja1993-sketch (a draft on GitHub). The platform function and its Linux
test are taken as they are. The call moved: the write-back it was written for is now shadow_write_back in
runtime/vk_memory.c (a file other sessions are changing), where it covers the runs of pages a submission
changed, and the setting is registered in cfg.c and described in nx2navi.ini.example, which also says
that the lazy write-back stays off with shadow storage.
The Windows files compile; the Linux code and its test are not compiled or run here.
Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
