IPVS netns shutdown/startup dead-lock

ip_vs_mutext is used by both netns shutdown code and startup
and both implicit uses sk_lock-AF_INET mutex.

cleanup CPU-1         startup CPU-2
ip_vs_dst_event()     ip_vs_genl_set_cmd()
 sk_lock-AF_INET     __ip_vs_mutex
                     sk_lock-AF_INET
__ip_vs_mutex
* DEAD LOCK *

A new mutex placed in ip_vs netns struct called sync_mutex is added.

Comments from Julian and Simon added.
This patch has been running for more than 3 month now and it seems to work.

Ver. 3
    IP_VS_SO_GET_DAEMON in do_ip_vs_get_ctl protected by sync_mutex
    instead of __ip_vs_mutex as sugested by Julian.

Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Hans Schillstrom
2011-10-11 10:54:35 +09:00
committed by Pablo Neira Ayuso
parent 98d9ae841a
commit ae1d48b23d
3 changed files with 89 additions and 53 deletions

View File

@@ -900,6 +900,7 @@ struct netns_ipvs {
volatile int sync_state;
volatile int master_syncid;
volatile int backup_syncid;
struct mutex sync_mutex;
/* multicast interface name */
char master_mcast_ifn[IP_VS_IFNAME_MAXLEN];
char backup_mcast_ifn[IP_VS_IFNAME_MAXLEN];