diff options
author | Eric Dumazet <edumazet@google.com> | 2014-09-22 13:38:16 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2014-09-22 18:31:18 -0400 |
commit | a35165ca101695aa2cc5a6300ef69ae60be39a49 (patch) | |
tree | d9f2aa4a8b447c524c4803d8e087a54d75698d2f | |
parent | 84de67b29882efaacd05861f41e749c5e8f0c3ed (diff) |
ipv4: do not use this_cpu_ptr() in preemptible context
this_cpu_ptr() in preemptible context is generally bad
Sep 22 05:05:55 br kernel: [ 94.608310] BUG: using smp_processor_id()
in
preemptible [00000000] code: ip/2261
Sep 22 05:05:55 br kernel: [ 94.608316] caller is
tunnel_dst_set.isra.28+0x20/0x60 [ip_tunnel]
Sep 22 05:05:55 br kernel: [ 94.608319] CPU: 3 PID: 2261 Comm: ip Not
tainted
3.17.0-rc5 #82
We can simply use raw_cpu_ptr(), as preemption is safe in these
contexts.
Should fix https://bugzilla.kernel.org/show_bug.cgi?id=84991
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Joe <joe9mail@gmail.com>
Fixes: 9a4aa9af447f ("ipv4: Use percpu Cache route in IP tunnels")
Acked-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/ipv4/ip_tunnel.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index afed1aac2638..bd41dd1948b6 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c | |||
@@ -79,10 +79,10 @@ static void __tunnel_dst_set(struct ip_tunnel_dst *idst, | |||
79 | idst->saddr = saddr; | 79 | idst->saddr = saddr; |
80 | } | 80 | } |
81 | 81 | ||
82 | static void tunnel_dst_set(struct ip_tunnel *t, | 82 | static noinline void tunnel_dst_set(struct ip_tunnel *t, |
83 | struct dst_entry *dst, __be32 saddr) | 83 | struct dst_entry *dst, __be32 saddr) |
84 | { | 84 | { |
85 | __tunnel_dst_set(this_cpu_ptr(t->dst_cache), dst, saddr); | 85 | __tunnel_dst_set(raw_cpu_ptr(t->dst_cache), dst, saddr); |
86 | } | 86 | } |
87 | 87 | ||
88 | static void tunnel_dst_reset(struct ip_tunnel *t) | 88 | static void tunnel_dst_reset(struct ip_tunnel *t) |
@@ -106,7 +106,7 @@ static struct rtable *tunnel_rtable_get(struct ip_tunnel *t, | |||
106 | struct dst_entry *dst; | 106 | struct dst_entry *dst; |
107 | 107 | ||
108 | rcu_read_lock(); | 108 | rcu_read_lock(); |
109 | idst = this_cpu_ptr(t->dst_cache); | 109 | idst = raw_cpu_ptr(t->dst_cache); |
110 | dst = rcu_dereference(idst->dst); | 110 | dst = rcu_dereference(idst->dst); |
111 | if (dst && !atomic_inc_not_zero(&dst->__refcnt)) | 111 | if (dst && !atomic_inc_not_zero(&dst->__refcnt)) |
112 | dst = NULL; | 112 | dst = NULL; |