From: Wei Wang <wei...@google.com> After rwlock is replaced with rcu and spinlock, route lookup can happen simultanously with route deletion. This patch removes the call to free_percpu(rt->rt6i_pcpu) from rt6_release() to avoid the race condition between rt6_release() and rt6_get_pcpu_route(). And as free_percpu(rt->rt6i_pcpu) is already called in ip6_dst_destroy() after the rcu grace period, it is safe to do this change.
Signed-off-by: Wei Wang <wei...@google.com> Signed-off-by: Martin KaFai Lau <ka...@fb.com> Signed-off-by: Eric Dumazet <eduma...@google.com> --- net/ipv6/ip6_fib.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index 9c8e704e6af7..eee392f7b1f6 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -190,9 +190,6 @@ void rt6_free_pcpu(struct rt6_info *non_pcpu_rt) *ppcpu_rt = NULL; } } - - free_percpu(non_pcpu_rt->rt6i_pcpu); - non_pcpu_rt->rt6i_pcpu = NULL; } EXPORT_SYMBOL_GPL(rt6_free_pcpu); -- 2.14.2.920.gcf0c67979c-goog