On Tue, Jul 14, 2015 at 04:48:24PM -0700, David Rientjes wrote:
> On Tue, 14 Jul 2015, Paul E. McKenney wrote:
>
> > commit a1992f2f3b8e174d740a8f764d0d51344bed2eed
> > Author: Paul E. McKenney <paul...@linux.vnet.ibm.com>
> > Date: Tue Jul 14 16:24:14 2015 -0700
> >
> > rcu: Don't disable CPU hotplug during OOM notifiers
> >
> > RCU's rcu_oom_notify() disables CPU hotplug in order to stabilize the
> > list of online CPUs, which it traverses. However, this is completely
> > pointless because smp_call_function_single() will quietly fail if
> > invoked
> > on an offline CPU. Because the count of requests is incremented in the
> > rcu_oom_notify_cpu() function that is remotely invoked, everything works
> > nicely even in the face of concurrent CPU-hotplug operations.
> >
> > Furthermore, in recent kernels, invoking get_online_cpus() from an OOM
> > notifier can result in deadlock. This commit therefore removes the
> > call to get_online_cpus() and put_online_cpus() from rcu_oom_notify().
> >
> > Reported-by: Marcin Ślusarz <marcin.slus...@gmail.com>
> > Reported-by: David Rientjes <rient...@google.com>
> > Signed-off-by: Paul E. McKenney <paul...@linux.vnet.ibm.com>
>
> Acked-by: David Rientjes <rient...@google.com>
Thank you!
Any news on whether or not it solves the problem?
Thanx, Paul
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