Hi I would like to ask about one difficult problem about people. currently, direct-io implementation has big sick about VM interaction. it assume get_user_pages() can pin the target pages in page's mm. but it doesn't. fork and cow might replace the relationship between task's mm and pages. therefore cuncurrent directio and fork can corrupt the process's data. There was two proposal in past day. 1) introduce new page flags 2) introduce new lock. unfortunately both proposal got strong complaint from other developers. then, we still have this issue. I don't have clever idea. I hope discuss how to fix or give it up. thanks to linus. his recent read_pagemap discussion restre my memory that I need post this mail. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>