On Mon, Nov 28, 2011 at 12:33:31PM +0530, Balbir Singh wrote: > On Wed, Nov 23, 2011 at 9:12 PM, Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > > From: Johannes Weiner <jweiner@xxxxxxxxxx> > > > > Pages have their corresponding page_cgroup descriptors set up before > > they are used in userspace, and thus managed by a memory cgroup. > > > > The only time where lookup_page_cgroup() can return NULL is in the > > page sanity checking code that executes while feeding pages into the > > page allocator for the first time. > > > > This is a legacy check from the days when we allocated PC during fault > time on demand. It might make sense to assert on !pc in DEBUG_VM mode > at some point in the future I don't think a BUG_ON bears more information than a null-pointer dereference. -- 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>