[PATCH 3.17 024/122] bonding: fix curr_active_slave/carrier with loadbalance arp monitoring

2014-12-05 Thread Greg Kroah-Hartman
3.17-stable review patch.  If anyone has any objections, please let me know.

--

From: Nikolay Aleksandrov 

[ Upstream commit b8e4500f42fe4464a33a887579147050bed8fcef ]

Since commit 6fde8f037e60 ("bonding: fix locking in
bond_loadbalance_arp_mon()") we can have a stale bond carrier state and
stale curr_active_slave when using arp monitoring in loadbalance modes. The
reason is that in bond_loadbalance_arp_mon() we can't have
do_failover == true but slave_state_changed == false, whenever do_failover
is true then slave_state_changed is also true. Then the following piece
from bond_loadbalance_arp_mon():
if (slave_state_changed) {
bond_slave_state_change(bond);
if (BOND_MODE(bond) == BOND_MODE_XOR)
bond_update_slave_arr(bond, NULL);
} else if (do_failover) {
block_netpoll_tx();
bond_select_active_slave(bond);
unblock_netpoll_tx();
}

will execute only the first branch, always and regardless of do_failover.
Since these two events aren't related in such way, we need to decouple and
consider them separately.

For example this issue could lead to the following result:
Bonding Mode: load balancing (round-robin)
*MII Status: down*
MII Polling Interval (ms): 0
Up Delay (ms): 0
Down Delay (ms): 0
ARP Polling Interval (ms): 100
ARP IP target/s (n.n.n.n form): 192.168.9.2

Slave Interface: ens12
*MII Status: up*
Speed: 1 Mbps
Duplex: full
Link Failure Count: 2
Permanent HW addr: 00:0f:53:01:42:2c
Slave queue ID: 0

Slave Interface: eth1
*MII Status: up*
Speed: Unknown
Duplex: Unknown
Link Failure Count: 70
Permanent HW addr: 52:54:00:2f:0f:8e
Slave queue ID: 0

Since some interfaces are up, then the status of the bond should also be
up, but it will never change unless something invokes bond_set_carrier()
(i.e. enslave, bond_select_active_slave etc). Now, if I force the
calling of bond_select_active_slave via for example changing
primary_reselect (it can change in any mode), then the MII status goes to
"up" because it calls bond_select_active_slave() which should've been done
from bond_loadbalance_arp_mon() itself.

CC: Veaceslav Falico 
CC: Jay Vosburgh 
CC: Andy Gospodarek 
CC: Ding Tianhong 

Fixes: 6fde8f037e60 ("bonding: fix locking in bond_loadbalance_arp_mon()")
Signed-off-by: Nikolay Aleksandrov 
Acked-by: Veaceslav Falico 
Acked-by: Andy Gospodarek 
Acked-by: Ding Tianhong 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman 
---
 drivers/net/bonding/bond_main.c |4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2498,9 +2498,9 @@ static void bond_loadbalance_arp_mon(str
if (!rtnl_trylock())
goto re_arm;
 
-   if (slave_state_changed) {
+   if (slave_state_changed)
bond_slave_state_change(bond);
-   } else if (do_failover) {
+   if (do_failover) {
/* the bond_select_active_slave must hold RTNL
 * and curr_slave_lock for write.
 */


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[PATCH 3.17 024/122] bonding: fix curr_active_slave/carrier with loadbalance arp monitoring

2014-12-05 Thread Greg Kroah-Hartman
3.17-stable review patch.  If anyone has any objections, please let me know.

--

From: Nikolay Aleksandrov niko...@redhat.com

[ Upstream commit b8e4500f42fe4464a33a887579147050bed8fcef ]

Since commit 6fde8f037e60 (bonding: fix locking in
bond_loadbalance_arp_mon()) we can have a stale bond carrier state and
stale curr_active_slave when using arp monitoring in loadbalance modes. The
reason is that in bond_loadbalance_arp_mon() we can't have
do_failover == true but slave_state_changed == false, whenever do_failover
is true then slave_state_changed is also true. Then the following piece
from bond_loadbalance_arp_mon():
if (slave_state_changed) {
bond_slave_state_change(bond);
if (BOND_MODE(bond) == BOND_MODE_XOR)
bond_update_slave_arr(bond, NULL);
} else if (do_failover) {
block_netpoll_tx();
bond_select_active_slave(bond);
unblock_netpoll_tx();
}

will execute only the first branch, always and regardless of do_failover.
Since these two events aren't related in such way, we need to decouple and
consider them separately.

For example this issue could lead to the following result:
Bonding Mode: load balancing (round-robin)
*MII Status: down*
MII Polling Interval (ms): 0
Up Delay (ms): 0
Down Delay (ms): 0
ARP Polling Interval (ms): 100
ARP IP target/s (n.n.n.n form): 192.168.9.2

Slave Interface: ens12
*MII Status: up*
Speed: 1 Mbps
Duplex: full
Link Failure Count: 2
Permanent HW addr: 00:0f:53:01:42:2c
Slave queue ID: 0

Slave Interface: eth1
*MII Status: up*
Speed: Unknown
Duplex: Unknown
Link Failure Count: 70
Permanent HW addr: 52:54:00:2f:0f:8e
Slave queue ID: 0

Since some interfaces are up, then the status of the bond should also be
up, but it will never change unless something invokes bond_set_carrier()
(i.e. enslave, bond_select_active_slave etc). Now, if I force the
calling of bond_select_active_slave via for example changing
primary_reselect (it can change in any mode), then the MII status goes to
up because it calls bond_select_active_slave() which should've been done
from bond_loadbalance_arp_mon() itself.

CC: Veaceslav Falico vfal...@gmail.com
CC: Jay Vosburgh j.vosbu...@gmail.com
CC: Andy Gospodarek a...@greyhouse.net
CC: Ding Tianhong dingtianh...@huawei.com

Fixes: 6fde8f037e60 (bonding: fix locking in bond_loadbalance_arp_mon())
Signed-off-by: Nikolay Aleksandrov niko...@redhat.com
Acked-by: Veaceslav Falico vfal...@gmail.com
Acked-by: Andy Gospodarek go...@cumulusnetworks.com
Acked-by: Ding Tianhong dingtianh...@huawei.com
Signed-off-by: David S. Miller da...@davemloft.net
Signed-off-by: Greg Kroah-Hartman gre...@linuxfoundation.org
---
 drivers/net/bonding/bond_main.c |4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2498,9 +2498,9 @@ static void bond_loadbalance_arp_mon(str
if (!rtnl_trylock())
goto re_arm;
 
-   if (slave_state_changed) {
+   if (slave_state_changed)
bond_slave_state_change(bond);
-   } else if (do_failover) {
+   if (do_failover) {
/* the bond_select_active_slave must hold RTNL
 * and curr_slave_lock for write.
 */


--
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the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/