From: Julian Anastasov <ja@xxxxxx> We used a global BH disable in LOCAL_OUT hook. Add _bh suffix to all places that need it and remove the disabling from LOCAL_OUT and sync code. Functions like ip_defrag need protection from BH, so add it. As for nf_nat_mangle_tcp_packet, it needs RCU lock. Signed-off-by: Julian Anastasov <ja@xxxxxx> Signed-off-by: Simon Horman <horms@xxxxxxxxxxxx> --- net/netfilter/ipvs/ip_vs_app.c | 4 ++-- net/netfilter/ipvs/ip_vs_conn.c | 30 +++++++++++++------------- net/netfilter/ipvs/ip_vs_core.c | 37 +++++++-------------------------- net/netfilter/ipvs/ip_vs_ftp.c | 2 ++ net/netfilter/ipvs/ip_vs_lblc.c | 4 ++-- net/netfilter/ipvs/ip_vs_lblcr.c | 12 +++++------ net/netfilter/ipvs/ip_vs_proto_sctp.c | 4 ++-- net/netfilter/ipvs/ip_vs_proto_tcp.c | 8 +++---- net/netfilter/ipvs/ip_vs_rr.c | 6 +++--- net/netfilter/ipvs/ip_vs_sync.c | 24 +++++++++------------ net/netfilter/ipvs/ip_vs_wrr.c | 4 ++-- net/netfilter/ipvs/ip_vs_xmit.c | 16 +++++++------- 12 files changed, 64 insertions(+), 87 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_app.c b/net/netfilter/ipvs/ip_vs_app.c index a956030..dfd7b65 100644 --- a/net/netfilter/ipvs/ip_vs_app.c +++ b/net/netfilter/ipvs/ip_vs_app.c @@ -352,14 +352,14 @@ static inline void vs_seq_update(struct ip_vs_conn *cp, struct ip_vs_seq *vseq, unsigned int flag, __u32 seq, int diff) { /* spinlock is to keep updating cp->flags atomic */ - spin_lock(&cp->lock); + spin_lock_bh(&cp->lock); if (!(cp->flags & flag) || after(seq, vseq->init_seq)) { vseq->previous_delta = vseq->delta; vseq->delta += diff; vseq->init_seq = seq; cp->flags |= flag; } - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); } static inline int app_tcp_pkt_out(struct ip_vs_conn *cp, struct sk_buff *skb, diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index 54de340..de64758 100644 --- a/net/netfilter/ipvs/ip_vs_conn.c +++ b/net/netfilter/ipvs/ip_vs_conn.c @@ -86,14 +86,14 @@ struct ip_vs_aligned_lock static struct ip_vs_aligned_lock __ip_vs_conntbl_lock_array[CT_LOCKARRAY_SIZE] __cacheline_aligned; -static inline void ct_write_lock(unsigned int key) +static inline void ct_write_lock_bh(unsigned int key) { - spin_lock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); + spin_lock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); } -static inline void ct_write_unlock(unsigned int key) +static inline void ct_write_unlock_bh(unsigned int key) { - spin_unlock(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); + spin_unlock_bh(&__ip_vs_conntbl_lock_array[key&CT_LOCKARRAY_MASK].l); } @@ -167,7 +167,7 @@ static inline int ip_vs_conn_hash(struct ip_vs_conn *cp) /* Hash by protocol, client address and port */ hash = ip_vs_conn_hashkey_conn(cp); - ct_write_lock(hash); + ct_write_lock_bh(hash); spin_lock(&cp->lock); if (!(cp->flags & IP_VS_CONN_F_HASHED)) { @@ -182,7 +182,7 @@ static inline int ip_vs_conn_hash(struct ip_vs_conn *cp) } spin_unlock(&cp->lock); - ct_write_unlock(hash); + ct_write_unlock_bh(hash); return ret; } @@ -200,7 +200,7 @@ static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp) /* unhash it and decrease its reference counter */ hash = ip_vs_conn_hashkey_conn(cp); - ct_write_lock(hash); + ct_write_lock_bh(hash); spin_lock(&cp->lock); if (cp->flags & IP_VS_CONN_F_HASHED) { @@ -212,7 +212,7 @@ static inline int ip_vs_conn_unhash(struct ip_vs_conn *cp) ret = 0; spin_unlock(&cp->lock); - ct_write_unlock(hash); + ct_write_unlock_bh(hash); return ret; } @@ -227,7 +227,7 @@ static inline bool ip_vs_conn_unlink(struct ip_vs_conn *cp) hash = ip_vs_conn_hashkey_conn(cp); - ct_write_lock(hash); + ct_write_lock_bh(hash); spin_lock(&cp->lock); if (cp->flags & IP_VS_CONN_F_HASHED) { @@ -242,7 +242,7 @@ static inline bool ip_vs_conn_unlink(struct ip_vs_conn *cp) ret = atomic_read(&cp->refcnt) ? false : true; spin_unlock(&cp->lock); - ct_write_unlock(hash); + ct_write_unlock_bh(hash); return ret; } @@ -462,13 +462,13 @@ void ip_vs_conn_put(struct ip_vs_conn *cp) void ip_vs_conn_fill_cport(struct ip_vs_conn *cp, __be16 cport) { if (ip_vs_conn_unhash(cp)) { - spin_lock(&cp->lock); + spin_lock_bh(&cp->lock); if (cp->flags & IP_VS_CONN_F_NO_CPORT) { atomic_dec(&ip_vs_conn_no_cport_cnt); cp->flags &= ~IP_VS_CONN_F_NO_CPORT; cp->cport = cport; } - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); /* hash on new dport */ ip_vs_conn_hash(cp); @@ -622,9 +622,9 @@ void ip_vs_try_bind_dest(struct ip_vs_conn *cp) if (dest) { struct ip_vs_proto_data *pd; - spin_lock(&cp->lock); + spin_lock_bh(&cp->lock); if (cp->dest) { - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); rcu_read_unlock(); return; } @@ -635,7 +635,7 @@ void ip_vs_try_bind_dest(struct ip_vs_conn *cp) ip_vs_unbind_app(cp); ip_vs_bind_dest(cp, dest); - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); /* Update its packet transmitter */ cp->packet_xmit = NULL; diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c index 79df3c6..f26fe33 100644 --- a/net/netfilter/ipvs/ip_vs_core.c +++ b/net/netfilter/ipvs/ip_vs_core.c @@ -638,8 +638,11 @@ static inline enum ip_defrag_users ip_vs_defrag_user(unsigned int hooknum) static inline int ip_vs_gather_frags(struct sk_buff *skb, u_int32_t user) { - int err = ip_defrag(skb, user); + int err; + local_bh_disable(); + err = ip_defrag(skb, user); + local_bh_enable(); if (!err) ip_send_check(ip_hdr(skb)); @@ -1217,13 +1220,7 @@ ip_vs_local_reply4(unsigned int hooknum, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - unsigned int verdict; - - /* Disable BH in LOCAL_OUT until all places are fixed */ - local_bh_disable(); - verdict = ip_vs_out(hooknum, skb, AF_INET); - local_bh_enable(); - return verdict; + return ip_vs_out(hooknum, skb, AF_INET); } #ifdef CONFIG_IP_VS_IPV6 @@ -1250,13 +1247,7 @@ ip_vs_local_reply6(unsigned int hooknum, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - unsigned int verdict; - - /* Disable BH in LOCAL_OUT until all places are fixed */ - local_bh_disable(); - verdict = ip_vs_out(hooknum, skb, AF_INET6); - local_bh_enable(); - return verdict; + return ip_vs_out(hooknum, skb, AF_INET6); } #endif @@ -1714,13 +1705,7 @@ ip_vs_local_request4(unsigned int hooknum, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - unsigned int verdict; - - /* Disable BH in LOCAL_OUT until all places are fixed */ - local_bh_disable(); - verdict = ip_vs_in(hooknum, skb, AF_INET); - local_bh_enable(); - return verdict; + return ip_vs_in(hooknum, skb, AF_INET); } #ifdef CONFIG_IP_VS_IPV6 @@ -1779,13 +1764,7 @@ ip_vs_local_request6(unsigned int hooknum, struct sk_buff *skb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - unsigned int verdict; - - /* Disable BH in LOCAL_OUT until all places are fixed */ - local_bh_disable(); - verdict = ip_vs_in(hooknum, skb, AF_INET6); - local_bh_enable(); - return verdict; + return ip_vs_in(hooknum, skb, AF_INET6); } #endif diff --git a/net/netfilter/ipvs/ip_vs_ftp.c b/net/netfilter/ipvs/ip_vs_ftp.c index 7f90825..77c1732 100644 --- a/net/netfilter/ipvs/ip_vs_ftp.c +++ b/net/netfilter/ipvs/ip_vs_ftp.c @@ -267,10 +267,12 @@ static int ip_vs_ftp_out(struct ip_vs_app *app, struct ip_vs_conn *cp, * hopefully it will succeed on the retransmitted * packet. */ + rcu_read_lock(); ret = nf_nat_mangle_tcp_packet(skb, ct, ctinfo, iph->ihl * 4, start-data, end-start, buf, buf_len); + rcu_read_unlock(); if (ret) { ip_vs_nfct_expect_related(skb, ct, n_cp, IPPROTO_TCP, 0, 0); diff --git a/net/netfilter/ipvs/ip_vs_lblc.c b/net/netfilter/ipvs/ip_vs_lblc.c index d8e5238..b2cc252 100644 --- a/net/netfilter/ipvs/ip_vs_lblc.c +++ b/net/netfilter/ipvs/ip_vs_lblc.c @@ -527,10 +527,10 @@ ip_vs_lblc_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) } /* If we fail to create a cache entry, we'll just use the valid dest */ - spin_lock(&svc->sched_lock); + spin_lock_bh(&svc->sched_lock); if (!tbl->dead) ip_vs_lblc_new(tbl, &iph.daddr, dest); - spin_unlock(&svc->sched_lock); + spin_unlock_bh(&svc->sched_lock); out: IP_VS_DBG_BUF(6, "LBLC: destination IP address %s --> server %s:%d\n", diff --git a/net/netfilter/ipvs/ip_vs_lblcr.c b/net/netfilter/ipvs/ip_vs_lblcr.c index 041b7cc..feb9656 100644 --- a/net/netfilter/ipvs/ip_vs_lblcr.c +++ b/net/netfilter/ipvs/ip_vs_lblcr.c @@ -678,7 +678,7 @@ ip_vs_lblcr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) if (atomic_read(&en->set.size) > 1 && time_after(jiffies, en->set.lastmod + sysctl_lblcr_expiration(svc))) { - spin_lock(&svc->sched_lock); + spin_lock_bh(&svc->sched_lock); if (atomic_read(&en->set.size) > 1) { struct ip_vs_dest *m; @@ -686,7 +686,7 @@ ip_vs_lblcr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) if (m) ip_vs_dest_set_erase(&en->set, m); } - spin_unlock(&svc->sched_lock); + spin_unlock_bh(&svc->sched_lock); } /* If the destination is not overloaded, use it */ @@ -701,10 +701,10 @@ ip_vs_lblcr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) } /* Update our cache entry */ - spin_lock(&svc->sched_lock); + spin_lock_bh(&svc->sched_lock); if (!tbl->dead) ip_vs_dest_set_insert(&en->set, dest, true); - spin_unlock(&svc->sched_lock); + spin_unlock_bh(&svc->sched_lock); goto out; } @@ -716,10 +716,10 @@ ip_vs_lblcr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) } /* If we fail to create a cache entry, we'll just use the valid dest */ - spin_lock(&svc->sched_lock); + spin_lock_bh(&svc->sched_lock); if (!tbl->dead) ip_vs_lblcr_new(tbl, &iph.daddr, dest); - spin_unlock(&svc->sched_lock); + spin_unlock_bh(&svc->sched_lock); out: IP_VS_DBG_BUF(6, "LBLCR: destination IP address %s --> server %s:%d\n", diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c index 4de5176..6e14a7b 100644 --- a/net/netfilter/ipvs/ip_vs_proto_sctp.c +++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c @@ -994,9 +994,9 @@ static void sctp_state_transition(struct ip_vs_conn *cp, int direction, const struct sk_buff *skb, struct ip_vs_proto_data *pd) { - spin_lock(&cp->lock); + spin_lock_bh(&cp->lock); set_sctp_state(pd, cp, direction, skb); - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); } static inline __u16 sctp_app_hashkey(__be16 port) diff --git a/net/netfilter/ipvs/ip_vs_proto_tcp.c b/net/netfilter/ipvs/ip_vs_proto_tcp.c index 7de3342..50a1594 100644 --- a/net/netfilter/ipvs/ip_vs_proto_tcp.c +++ b/net/netfilter/ipvs/ip_vs_proto_tcp.c @@ -557,9 +557,9 @@ tcp_state_transition(struct ip_vs_conn *cp, int direction, if (th == NULL) return; - spin_lock(&cp->lock); + spin_lock_bh(&cp->lock); set_tcp_state(pd, cp, direction, th); - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); } static inline __u16 tcp_app_hashkey(__be16 port) @@ -655,11 +655,11 @@ void ip_vs_tcp_conn_listen(struct net *net, struct ip_vs_conn *cp) { struct ip_vs_proto_data *pd = ip_vs_proto_data_get(net, IPPROTO_TCP); - spin_lock(&cp->lock); + spin_lock_bh(&cp->lock); cp->state = IP_VS_TCP_S_LISTEN; cp->timeout = (pd ? pd->timeout_table[IP_VS_TCP_S_LISTEN] : tcp_timeouts[IP_VS_TCP_S_LISTEN]); - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); } /* --------------------------------------------- diff --git a/net/netfilter/ipvs/ip_vs_rr.c b/net/netfilter/ipvs/ip_vs_rr.c index 749c98a..c35986c 100644 --- a/net/netfilter/ipvs/ip_vs_rr.c +++ b/net/netfilter/ipvs/ip_vs_rr.c @@ -63,7 +63,7 @@ ip_vs_rr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) IP_VS_DBG(6, "%s(): Scheduling...\n", __func__); - spin_lock(&svc->sched_lock); + spin_lock_bh(&svc->sched_lock); p = (struct list_head *) svc->sched_data; last = dest = list_entry(p, struct ip_vs_dest, n_list); @@ -85,13 +85,13 @@ ip_vs_rr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) } while (pass < 2 && p != &svc->destinations); stop: - spin_unlock(&svc->sched_lock); + spin_unlock_bh(&svc->sched_lock); ip_vs_scheduler_err(svc, "no destination available"); return NULL; out: svc->sched_data = &dest->n_list; - spin_unlock(&svc->sched_lock); + spin_unlock_bh(&svc->sched_lock); IP_VS_DBG_BUF(6, "RR: server %s:%u " "activeconns %d refcnt %d weight %d\n", IP_VS_DBG_ADDR(svc->af, &dest->addr), ntohs(dest->port), diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c index 9724174..8e57077 100644 --- a/net/netfilter/ipvs/ip_vs_sync.c +++ b/net/netfilter/ipvs/ip_vs_sync.c @@ -531,9 +531,9 @@ static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp, if (!ip_vs_sync_conn_needed(ipvs, cp, pkts)) return; - spin_lock(&ipvs->sync_buff_lock); + spin_lock_bh(&ipvs->sync_buff_lock); if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) { - spin_unlock(&ipvs->sync_buff_lock); + spin_unlock_bh(&ipvs->sync_buff_lock); return; } @@ -552,7 +552,7 @@ static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp, if (!buff) { buff = ip_vs_sync_buff_create_v0(ipvs); if (!buff) { - spin_unlock(&ipvs->sync_buff_lock); + spin_unlock_bh(&ipvs->sync_buff_lock); pr_err("ip_vs_sync_buff_create failed.\n"); return; } @@ -590,7 +590,7 @@ static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp, sb_queue_tail(ipvs, ms); ms->sync_buff = NULL; } - spin_unlock(&ipvs->sync_buff_lock); + spin_unlock_bh(&ipvs->sync_buff_lock); /* synchronize its controller if it has */ cp = cp->control; @@ -641,9 +641,9 @@ sloop: pe_name_len = strnlen(cp->pe->name, IP_VS_PENAME_MAXLEN); } - spin_lock(&ipvs->sync_buff_lock); + spin_lock_bh(&ipvs->sync_buff_lock); if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) { - spin_unlock(&ipvs->sync_buff_lock); + spin_unlock_bh(&ipvs->sync_buff_lock); return; } @@ -683,7 +683,7 @@ sloop: if (!buff) { buff = ip_vs_sync_buff_create(ipvs); if (!buff) { - spin_unlock(&ipvs->sync_buff_lock); + spin_unlock_bh(&ipvs->sync_buff_lock); pr_err("ip_vs_sync_buff_create failed.\n"); return; } @@ -750,7 +750,7 @@ sloop: } } - spin_unlock(&ipvs->sync_buff_lock); + spin_unlock_bh(&ipvs->sync_buff_lock); control: /* synchronize its controller if it has */ @@ -843,7 +843,7 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param, kfree(param->pe_data); dest = cp->dest; - spin_lock(&cp->lock); + spin_lock_bh(&cp->lock); if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE && !(flags & IP_VS_CONN_F_TEMPLATE) && dest) { if (flags & IP_VS_CONN_F_INACTIVE) { @@ -857,7 +857,7 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param, flags &= IP_VS_CONN_F_BACKUP_UPD_MASK; flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK; cp->flags = flags; - spin_unlock(&cp->lock); + spin_unlock_bh(&cp->lock); if (!dest) ip_vs_try_bind_dest(cp); } else { @@ -1689,11 +1689,7 @@ static int sync_thread_backup(void *data) break; } - /* disable bottom half, because it accesses the data - shared by softirq while getting/creating conns */ - local_bh_disable(); ip_vs_process_message(tinfo->net, tinfo->buf, len); - local_bh_enable(); } } diff --git a/net/netfilter/ipvs/ip_vs_wrr.c b/net/netfilter/ipvs/ip_vs_wrr.c index 32c646e..0e68555 100644 --- a/net/netfilter/ipvs/ip_vs_wrr.c +++ b/net/netfilter/ipvs/ip_vs_wrr.c @@ -170,7 +170,7 @@ ip_vs_wrr_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) IP_VS_DBG(6, "%s(): Scheduling...\n", __func__); - spin_lock(&svc->sched_lock); + spin_lock_bh(&svc->sched_lock); dest = mark->cl; /* No available dests? */ if (mark->mw == 0) @@ -222,7 +222,7 @@ found: mark->cl = dest; out: - spin_unlock(&svc->sched_lock); + spin_unlock_bh(&svc->sched_lock); return dest; err_noavail: diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c index 3db7889..b75ff64 100644 --- a/net/netfilter/ipvs/ip_vs_xmit.c +++ b/net/netfilter/ipvs/ip_vs_xmit.c @@ -177,22 +177,22 @@ __ip_vs_get_out_rt(struct sk_buff *skb, struct ip_vs_dest *dest, rt = (struct rtable *) dest_dst->dst_cache; else { dest_dst = ip_vs_dest_dst_alloc(); - spin_lock(&dest->dst_lock); + spin_lock_bh(&dest->dst_lock); if (!dest_dst) { __ip_vs_dst_set(dest, NULL, NULL, 0); - spin_unlock(&dest->dst_lock); + spin_unlock_bh(&dest->dst_lock); goto err_unreach; } rt = do_output_route4(net, dest->addr.ip, rt_mode, &dest_dst->dst_saddr.ip); if (!rt) { __ip_vs_dst_set(dest, NULL, NULL, 0); - spin_unlock(&dest->dst_lock); + spin_unlock_bh(&dest->dst_lock); ip_vs_dest_dst_free(dest_dst); goto err_unreach; } __ip_vs_dst_set(dest, dest_dst, &rt->dst, 0); - spin_unlock(&dest->dst_lock); + spin_unlock_bh(&dest->dst_lock); IP_VS_DBG(10, "new dst %pI4, src %pI4, refcnt=%d\n", &dest->addr.ip, &dest_dst->dst_saddr.ip, atomic_read(&rt->dst.__refcnt)); @@ -358,10 +358,10 @@ __ip_vs_get_out_rt_v6(struct sk_buff *skb, struct ip_vs_dest *dest, u32 cookie; dest_dst = ip_vs_dest_dst_alloc(); - spin_lock(&dest->dst_lock); + spin_lock_bh(&dest->dst_lock); if (!dest_dst) { __ip_vs_dst_set(dest, NULL, NULL, 0); - spin_unlock(&dest->dst_lock); + spin_unlock_bh(&dest->dst_lock); goto err_unreach; } dst = __ip_vs_route_output_v6(net, &dest->addr.in6, @@ -369,14 +369,14 @@ __ip_vs_get_out_rt_v6(struct sk_buff *skb, struct ip_vs_dest *dest, do_xfrm); if (!dst) { __ip_vs_dst_set(dest, NULL, NULL, 0); - spin_unlock(&dest->dst_lock); + spin_unlock_bh(&dest->dst_lock); ip_vs_dest_dst_free(dest_dst); goto err_unreach; } rt = (struct rt6_info *) dst; cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; __ip_vs_dst_set(dest, dest_dst, &rt->dst, cookie); - spin_unlock(&dest->dst_lock); + spin_unlock_bh(&dest->dst_lock); IP_VS_DBG(10, "new dst %pI6, src %pI6, refcnt=%d\n", &dest->addr.in6, &dest_dst->dst_saddr.in6, atomic_read(&rt->dst.__refcnt)); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html