From aac4dddc358acfd9d98b20024a42c34dfab31c39 Mon Sep 17 00:00:00 2001 From: Eric Dumazet 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 Signed-off-by: David S. Miller --- 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; }