On Tue, 23 Nov 2010 22:02:55 +0100 Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > On Tue, Nov 23, 2010 at 12:16:06PM -0800, Andrew Morton wrote: > > On Tue, 23 Nov 2010 15:48:50 +0200 > > "Kirill A. Shutsemov" <kirill@xxxxxxxxxxxxx> wrote: > > > > > ------------[ cut here ]------------ > > > kernel BUG at mm/memcontrol.c:2155! > > > > This bug has been there for a year, from which I conclude people don't > > run memcg on uniprocessor machines a lot. > > > > Which is a bit sad, really. Small machines need resource control too, > > perhaps more than large ones.. > > Admittedly, this patch is compile-tested on UP only, but it should be > obvious enough. > > --- > From: Johannes Weiner <hannes@xxxxxxxxxxx> > Subject: [patch] memcg: fix page cgroup lock assert on UP > > Page cgroup locking primitives use the bit spinlock API functions, > which do nothing on UP. > > Thus, checking the lock state can not be done by looking at the bit > directly, but one has to go through the bit spinlock API as well. > > This fixes a guaranteed UP bug, where asserting the page cgroup lock > bit as a sanity check crashes the kernel. > hm, your patch is the same as Kirill's, except you named it page_is_cgroup_locked() rather than is_page_cgroup_locked(). I guess page_is_cgroup_locked() is a bit better. -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>