From aac4dddc358acfd9d98b20024a42c34dfab31c39 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 1 Jun 2010 00:26:58 -0700
Subject: [PATCH] ipv6: get rid of ipip6_prl_lock
As noticed by Julia Lawall, ipip6_tunnel_add_prl() incorrectly calls
kzallloc(..., GFP_KERNEL) while a spinlock is held. She provided
a patch to use GFP_ATOMIC instead.
One possibility would be to convert this spinlock to a mutex, or
preallocate the thing before taking the lock.
After RCU conversion, it appears we dont need this lock, since
caller already holds RTNL
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/ipv6/sit.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index e51e650ea80b..702c532ec21e 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -249,8 +249,6 @@ failed:
return NULL;
}
-static DEFINE_SPINLOCK(ipip6_prl_lock);
-
#define for_each_prl_rcu(start) \
for (prl = rcu_dereference(start); \
prl; \
@@ -340,7 +338,7 @@ ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
if (a->addr == htonl(INADDR_ANY))
return -EINVAL;
- spin_lock(&ipip6_prl_lock);
+ ASSERT_RTNL();
for (p = t->prl; p; p = p->next) {
if (p->addr == a->addr) {
@@ -370,7 +368,6 @@ ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
t->prl_count++;
rcu_assign_pointer(t->prl, p);
out:
- spin_unlock(&ipip6_prl_lock);
return err;
}
@@ -397,7 +394,7 @@ ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
struct ip_tunnel_prl_entry *x, **p;
int err = 0;
- spin_lock(&ipip6_prl_lock);
+ ASSERT_RTNL();
if (a && a->addr != htonl(INADDR_ANY)) {
for (p = &t->prl; *p; p = &(*p)->next) {
@@ -419,7 +416,6 @@ ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
}
}
out:
- spin_unlock(&ipip6_prl_lock);
return err;
}
--
2.20.1