On Fri, May 30, 2014 at 10:21:13AM +1000, Dave Chinner wrote: > On Thu, May 29, 2014 at 08:06:49PM -0400, Dave Jones wrote: > > On Fri, May 30, 2014 at 09:53:08AM +1000, Dave Chinner wrote: > > > > > That sounds like a plan. Perhaps it would be useful to add a > > > WARN_ON_ONCE(stack_usage > 8k) (or some other arbitrary depth beyond > > > 8k) so that we get some indication that we're hitting a deep stack > > > but the system otherwise keeps functioning. That gives us some > > > motivation to keep stack usage down but isn't a fatal problem like > > > it is now.... > > > > We have check_stack_usage() and DEBUG_STACK_USAGE for this. > > Though it needs some tweaking if we move to 16K > > Right, but it doesn't throw loud warnings when a specific threshold > is reached - it just issues a quiet message when a process exits > telling you what the maximum was without giving us a stack to chew > on.... But we could enhance the inform so notice the risk to the user. as follow ... "kworker/u24:1 (94) used greatest stack depth: 8K bytes left, it means there is some horrible stack hogger in your kernel. Please report it the LKML and enable stacktrace to investigate who is culprit" > > Cheers, > > Dave. > -- > Dave Chinner > david@xxxxxxxxxxxxx > > -- > 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> -- Kind regards, Minchan Kim -- 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>