Messages in this thread | | | Date | Fri, 6 Jun 2014 15:17:49 -0700 | From | "Paul E. McKenney" <> | Subject | Re: Multitude of dst obsolescense race conditions |
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On Fri, Jun 06, 2014 at 11:57:10AM -0700, Eric Dumazet wrote: > On Fri, 2014-06-06 at 11:12 -0700, Paul E. McKenney wrote: > > > It is probably just be me getting lost in the code, but I am not seeing > > a synchronize_rcu(), call_rcu(), or synchronize_net() anywhere in > > dst_release() or the things that it calls. If there really isn't such > > a call, then I don't see how the above code is safe in the case where > > __sk_dst_set() is invoked on one CPU just after sk_dst_get() executes > > the rcu_dereference() on some other CPU. > > Well, this part is fine, dst_release() do not free dst that are > potentially stored in sk_dst_cache > > Only the refcount is decremented. > > The bug is elsewhere, we had another thread raising this issue on netdev > this morning. > > I am cooking a patch to clear the mess.
Ah, thank you, sorry for the noise!
Thanx, Paul
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