4.4-stable review patch. If anyone has any objections, please let me know.
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From: Paolo Abeni pabeni@redhat.com
commit f27337e16f2d0e52a8d05ea599ed13cd266ac291 upstream.
After the commit e09acddf873b ("ip_tunnel: replace dst_cache with generic implementation"), a preemption debug warning is triggered on ip4 tunnels updating; the dst cache helper needs to be invoked in unpreemptible context.
We don't need to load the cache on tunnel update, so this commit fixes the warning replacing the load with a dst cache reset, which is preempt safe.
Fixes: e09acddf873b ("ip_tunnel: replace dst_cache with generic implementation") Reported-by: Eric Dumazet eric.dumazet@gmail.com Signed-off-by: Paolo Abeni pabeni@redhat.com Acked-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Cc: Nathan Chancellor natechancellor@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/ipv4/ip_tunnel.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -327,12 +327,12 @@ static int ip_tunnel_bind_dev(struct net
if (!IS_ERR(rt)) { tdev = rt->dst.dev; - dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, - fl4.saddr); ip_rt_put(rt); } if (dev->type != ARPHRD_ETHER) dev->flags |= IFF_POINTOPOINT; + + dst_cache_reset(&tunnel->dst_cache); }
if (!tdev && tunnel->parms.link)