From mboxrd@z Thu Jan  1 00:00:00 1970
From: Martin KaFai Lau <kafai@fb.com>
Subject: Re: [PATCH net 3/3] ipv6: Fix dst_entry refcnt bugs in ip6_tunnel
Date: Wed, 2 Sep 2015 14:52:03 -0700
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Cc: netdev <netdev@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Kernel Team <kernel-team@fb.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Wed, Sep 02, 2015 at 02:30:45PM -0700, Eric Dumazet wrote:
> Object cannot be freed until all cpus have exited their RCU sections.
You meant the dst_destroy() here will wait for all cpus exited their RCU sections?

static inline void dst_free(struct dst_entry *dst)
{
	if (dst->obsolete > 0)
		return;
	if (!atomic_read(&dst->__refcnt)) {
		dst = dst_destroy(dst);
		if (!dst)
			return;
	}
	__dst_free(dst);
}