Hi Paul, On 11.07.2014 [08:14:05 -0700], Paul E. McKenney wrote: > On Fri, Jul 11, 2014 at 03:37:18PM +0800, Jiang Liu wrote: > > When CONFIG_HAVE_MEMORYLESS_NODES is enabled, cpu_to_node()/numa_node_id() > > may return a node without memory, and later cause system failure/panic > > when calling kmalloc_node() and friends with returned node id. > > So use cpu_to_mem()/numa_mem_id() instead to get the nearest node with > > memory for the/current cpu. > > > > If CONFIG_HAVE_MEMORYLESS_NODES is disabled, cpu_to_mem()/numa_mem_id() > > is the same as cpu_to_node()/numa_node_id(). > > > > Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> > > For the rcutorture piece: > > Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > > Or if you separate the kernel/rcu/rcutorture.c portion into a separate > patch, I will queue it separately. Just FYI, based upon a separate discussion with Tejun and others, it seems to be preferred to avoid the proliferation of cpu_to_mem throughout the kernel blindly. For kthread_create_on_node(), I'm going to try and fix the underlying issue and so you, as the caller, should still specify the NUMA node you are running the kthread on (cpu_to_node), not where you expect the memory to come from (cpu_to_mem). Thanks, Nish -- 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>