On Tue, 2014-06-10 at 23:32 -0400, Peter Hurley wrote: > While rcu list traversal over the vmap_area_list is safe, this may > arrive at different results than the spinlocked version. The rcu list > traversal version will not be a 'snapshot' of a single, valid instant > of the entire vmap_area_list, but rather a potential amalgam of > different list states. > > This is because the vmap_area_list can continue to change during > list traversal. As soon as we exit from get_vmalloc_info(), information can be obsolete anyway, especially if we held a spinlock for the whole list traversal. So using the spinlock is certainly not protecting anything in this regard. -- 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>