On Tue, 2014-05-06 at 09:32 -0700, Linus Torvalds wrote: > and what I think a GPU flush has to do is to do the actual flushes > when asked to (because that's what it will need to do to work with a > real TLB eventually), but if there's some crazy asynchronous > acknowledge thing from hardware, it's possible to perhaps wait for > that in the final phase (*before* we free the pages we gathered). Hrm, difficult. We have some pretty strong assumptions that ptep_clear_flush() is fully synchronous as far as I can tell... ie, your trick would work for the unmap case but everything else is still problematic. Ben. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>