1587dc37fa
If we take a WnR permission fault on a managed, writeable and dirty PTE, simply return success without calling the main fault handler. This situation can occur if multiple threads simultaneously access a clean writeable mapping and trigger WnR faults; losers of the race to mark the PTE dirty would end up calling the main fault handler, which had no work to do. Reported by: alc Reviewed by: alc MFC with: r350004 Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D21097