Dave Hansen <dave@xxxxxxxxxxxxxxxxxx> writes: > sys_move_pages() and sys_migrate_pages() are a pretty nice copy > and paste job of each other. They both take a pid, find the task > struct, and then grab a ref on the mm. They both also do an > rcu_read_unlock() after they've taken the mm and then proceed to > access 'task'. I think this is a bug in both cases. Can we share code? > > This patch takes the pid-to-task code along with the credential > and security checks in sys_move_pages() and sys_migrate_pages() > and consolidates them. It now takes a task reference in > the new function and requires the caller to drop it. I > believe this resolves the race. Looks good to me. Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx> BTW looks like we really need a better stress test for these syscalls. -Andi -- ak@xxxxxxxxxxxxxxx -- Speaking for myself only -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>