[PATCH v4 net-next 0/12] bonding: add an option to rely on unvalidated arp packets

[PATCH v4 net-next 0/12] bonding: add an option to rely on unvalidated arp packets

[Veaceslav Falico]

Hi,

v3 -> v4:
Per Nikolay's advise, remove the new bond_opts restriction on modes setting
for arp_validate.

v2 -> v3:
Per Jay's advise, use the 'filter' keyword instead of 'arp' one, and use
his text for documentation. Also, rebase on the latest net-next. Sorry for
the delay, didn't manage to send it before net-next was closed.

v1 -> v2:
Don't remove the 'all traffic' functionality - rather, add new arp_validate
options to specify that we want *only* unvalidated arps.

Currently, if arp_validate is off (0), slave_last_rx() returns the
slave->dev->last_rx, which is always updated on *any* packet received by
slave, and not only arps. This means that, if the validation of arps is
off, we're treating *any* incoming packet as a proof of slave being up, and
not only arps.

This might seem logical at the first glance, however it can cause a lot of
troubles and false-positives, one example would be:

The arp_ip_target is NOT accessible, however someone in the broadcast domain
spams with any broadcast traffic. This way bonding will be tricked that the
slave is still up (as in - can access arp_ip_target), while it's not.

The net_device->last_rx is already used in a lot of drivers (even though the
comment states to NOT do it :)), and it's also ugly to modify it from bonding.

However, some loadbalance setups might rely on the fact that even non-arp
traffic is a sign of slave being up - and we definitely can't break anyones
config - so an extension to arp_validate is needed.

So, to fix this, add an option for the user to specify if he wants to
filter out non-arp traffic on unvalidated slaves, remove the last_rx from
bonding, *always* call bond_arp_rcv() in slave's rx_handler (which is
bond_handle_frame), and if we spot an arp there with this option on - update
the slave->last_arp_rx - and use it instead of net_device->last_rx. Finally,
rename last_arp_rx to last_rx to reflect the changes.

Also rename slave->jiffies to ->last_link_up, to reflect better its
meaning, add the new option's documentation and update the arp_validate one
to be a bit more descriptive.

CC: Rob Landley <rob@landley.net>
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
CC: dingtianhong <dingtianhong@huawei.com>
CC: Nikolay Aleksandrov <nikolay@redhat.com>
CC: Neil Horman <nhorman@tuxdriver.com>
CC: Cong Wang <amwang@redhat.com>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>

---
 Documentation/networking/bonding.txt | 96 +++++++++++++++++++++++++-----------
 drivers/net/bonding/bond_main.c      | 56 +++++++++------------
 drivers/net/bonding/bond_options.c   | 17 ++++---
 drivers/net/bonding/bonding.h        | 26 ++++++----
 include/linux/netdevice.h            |  8 +--
 5 files changed, 117 insertions(+), 86 deletions(-)

[PATCH v4 net-next 01/12] bonding: remove bond->lock from bond_arp_rcv

[Veaceslav Falico]

We're always called with rcu_read_lock() held (bond_arp_rcv() is only
called from bond_handle_frame(), which is rx_handler and always called
under rcu from __netif_receive_skb_core() ).

The slave active/passive and/or bonding params can change in-flight, however
we don't really care about that - we only modify the last time packet was
received, which is harmless.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 3bce855..3c50bec 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2260,8 +2260,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
 	if (skb->protocol != __cpu_to_be16(ETH_P_ARP))
 		return RX_HANDLER_ANOTHER;
 
-	read_lock(&bond->lock);
-
 	if (!slave_do_arp_validate(bond, slave))
 		goto out_unlock;
 
@@ -2318,7 +2316,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
 		bond_validate_arp(bond, slave, tip, sip);
 
 out_unlock:
-	read_unlock(&bond->lock);
 	if (arp != (struct arphdr *)skb->data)
 		kfree(arp);
 	return RX_HANDLER_ANOTHER;
-- 
1.8.4

[PATCH v4 net-next 02/12] bonding: permit using arp_validate with non-ab modes

[Veaceslav Falico]

Currently it's disabled because it's sometimes hard, in typical configs, to
make it work - because of the nature how the loadbalance modes work - as
it's hard to deliver valid arp replies to correct slaves by the switch.

However we still can use arp_validation in loadbalance with several other
configs, per example with arp_validate == 2 for backup with one broadcast
domain, without the switch(es) doing any balancing - this way we'd be (a
bit more) sure that the slave is up.

So, enable it to let users decide which one works/suits them best. Also
remove the mode limitation from BOND_OPT_ARP_VALIDATE.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 Documentation/networking/bonding.txt | 6 +++---
 drivers/net/bonding/bond_main.c      | 4 ----
 drivers/net/bonding/bond_options.c   | 1 -
 3 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt
index 5cdb229..96b4ad8 100644
--- a/Documentation/networking/bonding.txt
+++ b/Documentation/networking/bonding.txt
@@ -270,9 +270,9 @@ arp_ip_target
 arp_validate
 
 	Specifies whether or not ARP probes and replies should be
-	validated in the active-backup mode.  This causes the ARP
-	monitor to examine the incoming ARP requests and replies, and
-	only consider a slave to be up if it is receiving the
+	validated in any mode that supports arp monitoring.  This causes
+	the ARP monitor to examine the incoming ARP requests and replies,
+	and only consider a slave to be up if it is receiving the
 	appropriate ARP traffic.
 
 	Possible values are:
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 3c50bec..91c0248 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4183,10 +4183,6 @@ static int bond_check_params(struct bond_params *params)
 	}
 
 	if (arp_validate) {
-		if (bond_mode != BOND_MODE_ACTIVEBACKUP) {
-			pr_err("arp_validate only supported in active-backup mode\n");
-			return -EINVAL;
-		}
 		if (!arp_interval) {
 			pr_err("arp_validate requires arp_interval\n");
 			return -EINVAL;
diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index f3eb44d..d566cab 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -151,7 +151,6 @@ static struct bond_option bond_opts[] = {
 		.id = BOND_OPT_ARP_VALIDATE,
 		.name = "arp_validate",
 		.desc = "validate src/dst of ARP probes",
-		.unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_ACTIVEBACKUP)),
 		.values = bond_arp_validate_tbl,
 		.set = bond_option_arp_validate_set
 	},
-- 
1.8.4

[PATCH v4 net-next 03/12] bonding: always update last_arp_rx on packet recieve

[Veaceslav Falico]

Currently we're updating the last_arp_rx only when we've validate the
packet, however afterwards we use it as 'ANY last packet received', but not
only validated ARPs.

Fix this by updating it in case of any packet received. It won't break the
arp_validation=0 because we, anyway, return the correct slave->dev->last_rx in
slave_last_rx().

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 91c0248..7747cc5 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2257,6 +2257,8 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
 	__be32 sip, tip;
 	int alen;
 
+	slave->last_arp_rx = jiffies;
+
 	if (skb->protocol != __cpu_to_be16(ETH_P_ARP))
 		return RX_HANDLER_ANOTHER;
 
-- 
1.8.4

[PATCH v4 net-next 04/12] bonding: always set recv_probe to bond_arp_rcv in arp monitor

[Veaceslav Falico]

Currently we only set bond_arp_rcv() if we're using arp_validate, however
this makes us skip updating last_arp_rx if we're not validating incoming
ARPs - thus, if arp_validate is off, last_arp_rx will never be updated.

Fix this by always setting up recv_probe = bond_arp_rcv, even if we're not
using arp_validate.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c    | 3 +--
 drivers/net/bonding/bond_options.c | 3 +--
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 7747cc5..257ee7f 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -3059,8 +3059,7 @@ static int bond_open(struct net_device *bond_dev)
 
 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
 		queue_delayed_work(bond->wq, &bond->arp_work, 0);
-		if (bond->params.arp_validate)
-			bond->recv_probe = bond_arp_rcv;
+		bond->recv_probe = bond_arp_rcv;
 	}
 
 	if (bond->params.mode == BOND_MODE_8023AD) {
diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index d566cab..6324baf 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -808,8 +808,7 @@ int bond_option_arp_interval_set(struct bonding *bond,
 			cancel_delayed_work_sync(&bond->arp_work);
 		} else {
 			/* arp_validate can be set only in active-backup mode */
-			if (bond->params.arp_validate)
-				bond->recv_probe = bond_arp_rcv;
+			bond->recv_probe = bond_arp_rcv;
 			cancel_delayed_work_sync(&bond->mii_work);
 			queue_delayed_work(bond->wq, &bond->arp_work, 0);
 		}
-- 
1.8.4

[PATCH v4 net-next 05/12] bonding: extend arp_validate to be able to receive unvalidated arp-only traffic

[Veaceslav Falico]

Currently we can either receive any traffic as a proff of slave being up,
or only *validated* arp traffic (i.e. with src/dst ip checked).

Add an option to be able to specify if we want to receive non-validated arp
traffic only.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_options.c | 13 ++++++++-----
 drivers/net/bonding/bonding.h      | 11 +++++++++++
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index 6324baf..713a90e 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -47,11 +47,14 @@ static struct bond_opt_value bond_xmit_hashtype_tbl[] = {
 };
 
 static struct bond_opt_value bond_arp_validate_tbl[] = {
-	{ "none",   BOND_ARP_VALIDATE_NONE,   BOND_VALFLAG_DEFAULT},
-	{ "active", BOND_ARP_VALIDATE_ACTIVE, 0},
-	{ "backup", BOND_ARP_VALIDATE_BACKUP, 0},
-	{ "all",    BOND_ARP_VALIDATE_ALL,    0},
-	{ NULL,     -1,                       0},
+	{ "none",		BOND_ARP_VALIDATE_NONE,		BOND_VALFLAG_DEFAULT},
+	{ "active",		BOND_ARP_VALIDATE_ACTIVE,	0},
+	{ "backup",		BOND_ARP_VALIDATE_BACKUP,	0},
+	{ "all",		BOND_ARP_VALIDATE_ALL,		0},
+	{ "filter",		BOND_ARP_FILTER,		0},
+	{ "filter_active",	BOND_ARP_FILTER_ACTIVE,		0},
+	{ "filter_backup",	BOND_ARP_FILTER_BACKUP,		0},
+	{ NULL,			-1,				0},
 };
 
 static struct bond_opt_value bond_arp_all_targets_tbl[] = {
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 86ccfb9..ab2e651 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -342,6 +342,11 @@ static inline bool bond_is_active_slave(struct slave *slave)
 #define BOND_ARP_VALIDATE_BACKUP	(1 << BOND_STATE_BACKUP)
 #define BOND_ARP_VALIDATE_ALL		(BOND_ARP_VALIDATE_ACTIVE | \
 					 BOND_ARP_VALIDATE_BACKUP)
+#define BOND_ARP_FILTER			(BOND_ARP_VALIDATE_ALL + 1)
+#define BOND_ARP_FILTER_ACTIVE		(BOND_ARP_VALIDATE_ACTIVE | \
+					 BOND_ARP_FILTER)
+#define BOND_ARP_FILTER_BACKUP		(BOND_ARP_VALIDATE_BACKUP | \
+					 BOND_ARP_FILTER)
 
 static inline int slave_do_arp_validate(struct bonding *bond,
 					struct slave *slave)
@@ -349,6 +354,12 @@ static inline int slave_do_arp_validate(struct bonding *bond,
 	return bond->params.arp_validate & (1 << bond_slave_state(slave));
 }
 
+static inline int slave_do_arp_validate_only(struct bonding *bond,
+					     struct slave *slave)
+{
+	return bond->params.arp_validate & BOND_ARP_FILTER;
+}
+
 /* Get the oldest arp which we've received on this slave for bond's
  * arp_targets.
  */
-- 
1.8.4

[PATCH v4 net-next 06/12] bonding: document the new _arp options for arp_validate

[Veaceslav Falico]

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 Documentation/networking/bonding.txt | 96 +++++++++++++++++++++++++-----------
 1 file changed, 66 insertions(+), 30 deletions(-)

diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt
index 96b4ad8..a383c00 100644
--- a/Documentation/networking/bonding.txt
+++ b/Documentation/networking/bonding.txt
@@ -270,16 +270,15 @@ arp_ip_target
 arp_validate
 
 	Specifies whether or not ARP probes and replies should be
-	validated in any mode that supports arp monitoring.  This causes
-	the ARP monitor to examine the incoming ARP requests and replies,
-	and only consider a slave to be up if it is receiving the
-	appropriate ARP traffic.
+	validated in any mode that supports arp monitoring, or whether
+	non-ARP traffic should be filtered (disregarded) for link
+	monitoring purposes.
 
 	Possible values are:
 
 	none or 0
 
-		No validation is performed.  This is the default.
+		No validation or filtering is performed.
 
 	active or 1
 
@@ -293,31 +292,68 @@ arp_validate
 
 		Validation is performed for all slaves.
 
-	For the active slave, the validation checks ARP replies to
-	confirm that they were generated by an arp_ip_target.  Since
-	backup slaves do not typically receive these replies, the
-	validation performed for backup slaves is on the ARP request
-	sent out via the active slave.  It is possible that some
-	switch or network configurations may result in situations
-	wherein the backup slaves do not receive the ARP requests; in
-	such a situation, validation of backup slaves must be
-	disabled.
-
-	The validation of ARP requests on backup slaves is mainly
-	helping bonding to decide which slaves are more likely to
-	work in case of the active slave failure, it doesn't really
-	guarantee that the backup slave will work if it's selected
-	as the next active slave.
-
-	This option is useful in network configurations in which
-	multiple bonding hosts are concurrently issuing ARPs to one or
-	more targets beyond a common switch.  Should the link between
-	the switch and target fail (but not the switch itself), the
-	probe traffic generated by the multiple bonding instances will
-	fool the standard ARP monitor into considering the links as
-	still up.  Use of the arp_validate option can resolve this, as
-	the ARP monitor will only consider ARP requests and replies
-	associated with its own instance of bonding.
+	filter or 4
+
+		Filtering is applied to all slaves. No validation is
+		performed.
+
+	filter_active or 5
+
+		Filtering is applied to all slaves, validation is performed
+		only for the active slave.
+
+	filter_backup or 6
+
+		Filtering is applied to all slaves, validation is performed
+		only for backup slaves.
+
+	Validation:
+
+	Enabling validation causes the ARP monitor to examine the incoming
+	ARP requests and replies, and only consider a slave to be up if it
+	is receiving the appropriate ARP traffic.
+
+	For an active slave, the validation checks ARP replies to confirm
+	that they were generated by an arp_ip_target.  Since backup slaves
+	do not typically receive these replies, the validation performed
+	for backup slaves is on the broadcast ARP request sent out via the
+	active slave.  It is possible that some switch or network
+	configurations may result in situations wherein the backup slaves
+	do not receive the ARP requests; in such a situation, validation
+	of backup slaves must be disabled.
+
+	The validation of ARP requests on backup slaves is mainly helping
+	bonding to decide which slaves are more likely to work in case of
+	the active slave failure, it doesn't really guarantee that the
+	backup slave will work if it's selected as the next active slave.
+
+	Validation is useful in network configurations in which multiple
+	bonding hosts are concurrently issuing ARPs to one or more targets
+	beyond a common switch.  Should the link between the switch and
+	target fail (but not the switch itself), the probe traffic
+	generated by the multiple bonding instances will fool the standard
+	ARP monitor into considering the links as still up.  Use of
+	validation can resolve this, as the ARP monitor will only consider
+	ARP requests and replies associated with its own instance of
+	bonding.
+
+	Filtering:
+
+	Enabling filtering causes the ARP monitor to only use incoming ARP
+	packets for link availability purposes.  Arriving packets that are
+	not ARPs are delivered normally, but do not count when determining
+	if a slave is available.
+
+	Filtering operates by only considering the reception of ARP
+	packets (any ARP packet, regardless of source or destination) when
+	determining if a slave has received traffic for link availability
+	purposes.
+
+	Filtering is useful in network configurations in which significant
+	levels of third party broadcast traffic would fool the standard
+	ARP monitor into considering the links as still up.  Use of
+	filtering can resolve this, as only ARP traffic is considered for
+	link availability purposes.
 
 	This option was added in bonding version 3.1.0.
 
-- 
1.8.4

[PATCH v4 net-next 07/12] bonding: use the new options to correctly set last_arp_rx

[Veaceslav Falico]

Now that the options are in place - arp_validate can be set to receive all
the traffic or only arp packets to verify if the slave is up, when the
slave isn't validated.

CC: Rob Landley <rob@landley.net>
CC: "David S. Miller" <davem@davemloft.net>
CC: Nikolay Aleksandrov <nikolay@redhat.com>
CC: Ding Tianhong <dingtianhong@huawei.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 257ee7f..3fe81cd 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2255,15 +2255,16 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
 	struct arphdr *arp = (struct arphdr *)skb->data;
 	unsigned char *arp_ptr;
 	__be32 sip, tip;
-	int alen;
+	int alen, is_arp = skb->protocol == __cpu_to_be16(ETH_P_ARP);
 
-	slave->last_arp_rx = jiffies;
-
-	if (skb->protocol != __cpu_to_be16(ETH_P_ARP))
+	if (!slave_do_arp_validate(bond, slave)) {
+		if ((slave_do_arp_validate_only(bond, slave) && is_arp) ||
+		    !slave_do_arp_validate_only(bond, slave))
+			slave->last_arp_rx = jiffies;
 		return RX_HANDLER_ANOTHER;
-
-	if (!slave_do_arp_validate(bond, slave))
-		goto out_unlock;
+	} else if (!is_arp) {
+		return RX_HANDLER_ANOTHER;
+	}
 
 	alen = arp_hdr_len(bond->dev);
 
-- 
1.8.4

[PATCH v4 net-next 08/12] bonding: use last_arp_rx in slave_last_rx()

[Veaceslav Falico]

Now that last_arp_rx really has the last time we've received any (validated or
not) ARP, we can use it in slave_last_rx() instead of slave->dev->last_rx.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bonding.h | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index ab2e651..ae20c5a 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -379,14 +379,10 @@ static inline unsigned long slave_oldest_target_arp_rx(struct bonding *bond,
 static inline unsigned long slave_last_rx(struct bonding *bond,
 					struct slave *slave)
 {
-	if (slave_do_arp_validate(bond, slave)) {
-		if (bond->params.arp_all_targets == BOND_ARP_TARGETS_ALL)
-			return slave_oldest_target_arp_rx(bond, slave);
-		else
-			return slave->last_arp_rx;
-	}
+	if (bond->params.arp_all_targets == BOND_ARP_TARGETS_ALL)
+		return slave_oldest_target_arp_rx(bond, slave);
 
-	return slave->dev->last_rx;
+	return slave->last_arp_rx;
 }
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
-- 
1.8.4

[PATCH v4 net-next 09/12] bonding: use last_arp_rx in bond_loadbalance_arp_mon()

[Veaceslav Falico]

Now that last_arp_rx correctly show the last time we've received an ARP, we
can use it safely instead of slave->dev->last_rx.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 3fe81cd..e7aab9a 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2372,7 +2372,7 @@ static void bond_loadbalance_arp_mon(struct work_struct *work)
 
 		if (slave->link != BOND_LINK_UP) {
 			if (bond_time_in_interval(bond, trans_start, 1) &&
-			    bond_time_in_interval(bond, slave->dev->last_rx, 1)) {
+			    bond_time_in_interval(bond, slave->last_arp_rx, 1)) {
 
 				slave->link  = BOND_LINK_UP;
 				slave_state_changed = 1;
@@ -2401,7 +2401,7 @@ static void bond_loadbalance_arp_mon(struct work_struct *work)
 			 * if we don't know our ip yet
 			 */
 			if (!bond_time_in_interval(bond, trans_start, 2) ||
-			    !bond_time_in_interval(bond, slave->dev->last_rx, 2)) {
+			    !bond_time_in_interval(bond, slave->last_arp_rx, 2)) {
 
 				slave->link  = BOND_LINK_DOWN;
 				slave_state_changed = 1;
-- 
1.8.4

[PATCH v4 net-next 10/12] bonding: remove useless updating of slave->dev->last_rx

[Veaceslav Falico]

Now that all the logic is handled via last_arp_rx, we don't need to use
last_rx.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c | 3 ---
 include/linux/netdevice.h       | 8 +-------
 2 files changed, 1 insertion(+), 10 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index e7aab9a..14e023d 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1115,9 +1115,6 @@ static rx_handler_result_t bond_handle_frame(struct sk_buff **pskb)
 	slave = bond_slave_get_rcu(skb->dev);
 	bond = slave->bond;
 
-	if (bond->params.arp_interval)
-		slave->dev->last_rx = jiffies;
-
 	recv_probe = ACCESS_ONCE(bond->recv_probe);
 	if (recv_probe) {
 		ret = recv_probe(skb, bond, slave);
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 430c51a..891432a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1312,13 +1312,7 @@ struct net_device {
 /*
  * Cache lines mostly used on receive path (including eth_type_trans())
  */
-	unsigned long		last_rx;	/* Time of last Rx
-						 * This should not be set in
-						 * drivers, unless really needed,
-						 * because network stack (bonding)
-						 * use it if/when necessary, to
-						 * avoid dirtying this cache line.
-						 */
+	unsigned long		last_rx;	/* Time of last Rx */
 
 	/* Interface address info used in eth_type_trans() */
 	unsigned char		*dev_addr;	/* hw address, (before bcast
-- 
1.8.4

[PATCH v4 net-next 11/12] bonding: trivial: rename slave->jiffies to ->last_link_up

[Veaceslav Falico]

slave->jiffies is updated every time the slave becomes active, which, for
bonding, means that its link is 'up'.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c | 20 ++++++++++----------
 drivers/net/bonding/bonding.h   |  3 ++-
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 14e023d..f6d56d9 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -798,7 +798,7 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
 		return;
 
 	if (new_active) {
-		new_active->jiffies = jiffies;
+		new_active->last_link_up = jiffies;
 
 		if (new_active->link == BOND_LINK_BACK) {
 			if (USES_PRIMARY(bond->params.mode)) {
@@ -1444,7 +1444,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 	}
 
 	if (new_slave->link != BOND_LINK_DOWN)
-		new_slave->jiffies = jiffies;
+		new_slave->last_link_up = jiffies;
 	pr_debug("Initial state of slave_dev is BOND_LINK_%s\n",
 		 new_slave->link == BOND_LINK_DOWN ? "DOWN" :
 		 (new_slave->link == BOND_LINK_UP ? "UP" : "BACK"));
@@ -1891,7 +1891,7 @@ static int bond_miimon_inspect(struct bonding *bond)
 				 * recovered before downdelay expired
 				 */
 				slave->link = BOND_LINK_UP;
-				slave->jiffies = jiffies;
+				slave->last_link_up = jiffies;
 				pr_info("%s: link status up again after %d ms for interface %s\n",
 					bond->dev->name,
 					(bond->params.downdelay - slave->delay) *
@@ -1966,7 +1966,7 @@ static void bond_miimon_commit(struct bonding *bond)
 
 		case BOND_LINK_UP:
 			slave->link = BOND_LINK_UP;
-			slave->jiffies = jiffies;
+			slave->last_link_up = jiffies;
 
 			if (bond->params.mode == BOND_MODE_8023AD) {
 				/* prevent it from being the active one */
@@ -2312,7 +2312,7 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
 		bond_validate_arp(bond, slave, sip, tip);
 	else if (bond->curr_active_slave &&
 		 time_after(slave_last_rx(bond, bond->curr_active_slave),
-			    bond->curr_active_slave->jiffies))
+			    bond->curr_active_slave->last_link_up))
 		bond_validate_arp(bond, slave, tip, sip);
 
 out_unlock:
@@ -2358,9 +2358,9 @@ static void bond_loadbalance_arp_mon(struct work_struct *work)
 	oldcurrent = ACCESS_ONCE(bond->curr_active_slave);
 	/* see if any of the previous devices are up now (i.e. they have
 	 * xmt and rcv traffic). the curr_active_slave does not come into
-	 * the picture unless it is null. also, slave->jiffies is not needed
-	 * here because we send an arp on each slave and give a slave as
-	 * long as it needs to get the tx/rx within the delta.
+	 * the picture unless it is null. also, slave->last_link_up is not
+	 * needed here because we send an arp on each slave and give a slave
+	 * as long as it needs to get the tx/rx within the delta.
 	 * TODO: what about up/down delay in arp mode? it wasn't here before
 	 *       so it can wait
 	 */
@@ -2486,7 +2486,7 @@ static int bond_ab_arp_inspect(struct bonding *bond)
 		 * active.  This avoids bouncing, as the last receive
 		 * times need a full ARP monitor cycle to be updated.
 		 */
-		if (bond_time_in_interval(bond, slave->jiffies, 2))
+		if (bond_time_in_interval(bond, slave->last_link_up, 2))
 			continue;
 
 		/*
@@ -2687,7 +2687,7 @@ static bool bond_ab_arp_probe(struct bonding *bond)
 	new_slave->link = BOND_LINK_BACK;
 	bond_set_slave_active_flags(new_slave);
 	bond_arp_send_all(bond, new_slave);
-	new_slave->jiffies = jiffies;
+	new_slave->last_link_up = jiffies;
 	rcu_assign_pointer(bond->current_arp_slave, new_slave);
 	rtnl_unlock();
 
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index ae20c5a..36db702 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -188,7 +188,8 @@ struct slave {
 	struct net_device *dev; /* first - useful for panic debug */
 	struct bonding *bond; /* our master */
 	int    delay;
-	unsigned long jiffies;
+	/* all three in jiffies */
+	unsigned long last_link_up;
 	unsigned long last_arp_rx;
 	unsigned long target_last_arp_rx[BOND_MAX_ARP_TARGETS];
 	s8     link;    /* one of BOND_LINK_XXXX */
-- 
1.8.4

[PATCH v4 net-next 12/12] bonding: rename last_arp_rx to last_rx

[Veaceslav Falico]

To reflect the new meaning.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
---
 drivers/net/bonding/bond_main.c | 12 ++++++------
 drivers/net/bonding/bonding.h   |  4 ++--
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index f6d56d9..ac4a1b8 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1397,10 +1397,10 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 
 	bond_update_speed_duplex(new_slave);
 
-	new_slave->last_arp_rx = jiffies -
+	new_slave->last_rx = jiffies -
 		(msecs_to_jiffies(bond->params.arp_interval) + 1);
 	for (i = 0; i < BOND_MAX_ARP_TARGETS; i++)
-		new_slave->target_last_arp_rx[i] = new_slave->last_arp_rx;
+		new_slave->target_last_arp_rx[i] = new_slave->last_rx;
 
 	if (bond->params.miimon && !bond->params.use_carrier) {
 		link_reporting = bond_check_dev_link(bond, slave_dev, 1);
@@ -2242,7 +2242,7 @@ static void bond_validate_arp(struct bonding *bond, struct slave *slave, __be32
 		pr_debug("bva: sip %pI4 not found in targets\n", &sip);
 		return;
 	}
-	slave->last_arp_rx = jiffies;
+	slave->last_rx = jiffies;
 	slave->target_last_arp_rx[i] = jiffies;
 }
 
@@ -2257,7 +2257,7 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
 	if (!slave_do_arp_validate(bond, slave)) {
 		if ((slave_do_arp_validate_only(bond, slave) && is_arp) ||
 		    !slave_do_arp_validate_only(bond, slave))
-			slave->last_arp_rx = jiffies;
+			slave->last_rx = jiffies;
 		return RX_HANDLER_ANOTHER;
 	} else if (!is_arp) {
 		return RX_HANDLER_ANOTHER;
@@ -2369,7 +2369,7 @@ static void bond_loadbalance_arp_mon(struct work_struct *work)
 
 		if (slave->link != BOND_LINK_UP) {
 			if (bond_time_in_interval(bond, trans_start, 1) &&
-			    bond_time_in_interval(bond, slave->last_arp_rx, 1)) {
+			    bond_time_in_interval(bond, slave->last_rx, 1)) {
 
 				slave->link  = BOND_LINK_UP;
 				slave_state_changed = 1;
@@ -2398,7 +2398,7 @@ static void bond_loadbalance_arp_mon(struct work_struct *work)
 			 * if we don't know our ip yet
 			 */
 			if (!bond_time_in_interval(bond, trans_start, 2) ||
-			    !bond_time_in_interval(bond, slave->last_arp_rx, 2)) {
+			    !bond_time_in_interval(bond, slave->last_rx, 2)) {
 
 				slave->link  = BOND_LINK_DOWN;
 				slave_state_changed = 1;
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 36db702..4303628 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -190,7 +190,7 @@ struct slave {
 	int    delay;
 	/* all three in jiffies */
 	unsigned long last_link_up;
-	unsigned long last_arp_rx;
+	unsigned long last_rx;
 	unsigned long target_last_arp_rx[BOND_MAX_ARP_TARGETS];
 	s8     link;    /* one of BOND_LINK_XXXX */
 	s8     new_link;
@@ -383,7 +383,7 @@ static inline unsigned long slave_last_rx(struct bonding *bond,
 	if (bond->params.arp_all_targets == BOND_ARP_TARGETS_ALL)
 		return slave_oldest_target_arp_rx(bond, slave);
 
-	return slave->last_arp_rx;
+	return slave->last_rx;
 }
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
-- 
1.8.4

RE: [PATCH v4 net-next 11/12] bonding: trivial: rename slave->jiffies to ->last_link_up

[David Laight]

> -	unsigned long jiffies;
> +	/* all three in jiffies */
> +	unsigned long last_link_up;
>  	unsigned long last_arp_rx;
>  	unsigned long target_last_arp_rx[BOND_MAX_ARP_TARGETS];

Personally I'd add _time to the member names (maybe not the last
as that is long enough already).
I sometimes go as far as adding the time units (eg _ms or _sec)
just to avoid confusion when reading the code much later on.

	David

Re: [PATCH v4 net-next 11/12] bonding: trivial: rename slave->jiffies to ->last_link_up

[Veaceslav Falico]

On Mon, Feb 17, 2014 at 03:02:36PM +0000, David Laight wrote:
>> -	unsigned long jiffies;
>> +	/* all three in jiffies */
>> +	unsigned long last_link_up;
>>  	unsigned long last_arp_rx;
>>  	unsigned long target_last_arp_rx[BOND_MAX_ARP_TARGETS];
>
>Personally I'd add _time to the member names (maybe not the last
>as that is long enough already).
>I sometimes go as far as adding the time units (eg _ms or _sec)
>just to avoid confusion when reading the code much later on.

Good idea, however current renaming follows the one used in bonding:

last_link_up, last_arp_rx (ripped from net_device, where last_rx is also
used), target_last_arp_rx, slave_last_rx() and some other. So it's somehow
consistent over all bonding and some other networking code (grepping by
last_rx yields a lot of results). And all of these are using jiffies as its
value.

I really like the general idea (to make it more readable, bonding really
lacks this part), however it's, IMO, a new patch(-set) material and doesn't
really fit in this patchset.

If you'd like to do that I would be really glad :), otherwise I'll add this
to my todo list.

Thanks a lot!

>
>	David
>
>
>

Re: [PATCH v4 net-next 02/12] bonding: permit using arp_validate with non-ab modes

[Nikolay Aleksandrov]

On 02/17/2014 03:41 PM, Veaceslav Falico wrote:
> Currently it's disabled because it's sometimes hard, in typical configs, to
> make it work - because of the nature how the loadbalance modes work - as
> it's hard to deliver valid arp replies to correct slaves by the switch.
> 
> However we still can use arp_validation in loadbalance with several other
> configs, per example with arp_validate == 2 for backup with one broadcast
> domain, without the switch(es) doing any balancing - this way we'd be (a
> bit more) sure that the slave is up.
> 
> So, enable it to let users decide which one works/suits them best. Also
> remove the mode limitation from BOND_OPT_ARP_VALIDATE.
> 
> CC: Jay Vosburgh <fubar@us.ibm.com>
> CC: Andy Gospodarek <andy@greyhouse.net>
> Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
> ---
>  Documentation/networking/bonding.txt | 6 +++---
>  drivers/net/bonding/bond_main.c      | 4 ----
>  drivers/net/bonding/bond_options.c   | 1 -
>  3 files changed, 3 insertions(+), 8 deletions(-)
> 
> diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt
> index 5cdb229..96b4ad8 100644
> --- a/Documentation/networking/bonding.txt
> +++ b/Documentation/networking/bonding.txt
> @@ -270,9 +270,9 @@ arp_ip_target
>  arp_validate
>  
>  	Specifies whether or not ARP probes and replies should be
> -	validated in the active-backup mode.  This causes the ARP
> -	monitor to examine the incoming ARP requests and replies, and
> -	only consider a slave to be up if it is receiving the
> +	validated in any mode that supports arp monitoring.  This causes
> +	the ARP monitor to examine the incoming ARP requests and replies,
> +	and only consider a slave to be up if it is receiving the
>  	appropriate ARP traffic.
>  
>  	Possible values are:
> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
> index 3c50bec..91c0248 100644
> --- a/drivers/net/bonding/bond_main.c
> +++ b/drivers/net/bonding/bond_main.c
> @@ -4183,10 +4183,6 @@ static int bond_check_params(struct bond_params *params)
>  	}
>  
>  	if (arp_validate) {
> -		if (bond_mode != BOND_MODE_ACTIVEBACKUP) {
> -			pr_err("arp_validate only supported in active-backup mode\n");
> -			return -EINVAL;
> -		}
>  		if (!arp_interval) {
>  			pr_err("arp_validate requires arp_interval\n");
>  			return -EINVAL;
> diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
> index f3eb44d..d566cab 100644
> --- a/drivers/net/bonding/bond_options.c
> +++ b/drivers/net/bonding/bond_options.c
> @@ -151,7 +151,6 @@ static struct bond_option bond_opts[] = {
>  		.id = BOND_OPT_ARP_VALIDATE,
>  		.name = "arp_validate",
>  		.desc = "validate src/dst of ARP probes",
> -		.unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_ACTIVEBACKUP)),
>  		.values = bond_arp_validate_tbl,
>  		.set = bond_option_arp_validate_set
>  	},
> 
Sorry for not noticing before, but I just remembered the reason why all the
checks are there when changing the recv_probe, especially from the options.
The problem was that lacp mode also uses the recv_probe, so after this patch we
can overwrite the recv_probe while it's running in lacp mode, because
bond_option_arp_validate_set changes the recv_probe. We can actually only set it
to NULL because arp_interval can't be set in those modes, but still we can break
the mode and there'll be need for at least down/up cycle to fix it.
I think rlb also uses the recv_probe so this applies to it as well.

Nik

Re: [PATCH v4 net-next 01/12] bonding: remove bond->lock from bond_arp_rcv

[Ding Tianhong]

On 2014/2/17 22:41, Veaceslav Falico wrote:
> We're always called with rcu_read_lock() held (bond_arp_rcv() is only
> called from bond_handle_frame(), which is rx_handler and always called
> under rcu from __netif_receive_skb_core() ).
> 
> The slave active/passive and/or bonding params can change in-flight, however
> we don't really care about that - we only modify the last time packet was
> received, which is harmless.
> 
> CC: Jay Vosburgh <fubar@us.ibm.com>
> CC: Andy Gospodarek <andy@greyhouse.net>
> Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
> ---
>  drivers/net/bonding/bond_main.c | 3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
> index 3bce855..3c50bec 100644
> --- a/drivers/net/bonding/bond_main.c
> +++ b/drivers/net/bonding/bond_main.c
> @@ -2260,8 +2260,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
>  	if (skb->protocol != __cpu_to_be16(ETH_P_ARP))
>  		return RX_HANDLER_ANOTHER;
>  
> -	read_lock(&bond->lock);
> -
>  	if (!slave_do_arp_validate(bond, slave))
>  		goto out_unlock;
>  
> @@ -2318,7 +2316,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
>  		bond_validate_arp(bond, slave, tip, sip);
>  
>  out_unlock:
> -	read_unlock(&bond->lock);
>  	if (arp != (struct arphdr *)skb->data)
>  		kfree(arp);
>  	return RX_HANDLER_ANOTHER;
> 

I think it is not enough, you should add rcu_dereference for bond->curr_active_slave, it may be changed during
the recv processing.

Regards
Ding

Re: [PATCH v4 net-next 01/12] bonding: remove bond->lock from bond_arp_rcv

[Veaceslav Falico]

On Tue, Feb 18, 2014 at 12:02:41PM +0800, Ding Tianhong wrote:
>On 2014/2/17 22:41, Veaceslav Falico wrote:
>> We're always called with rcu_read_lock() held (bond_arp_rcv() is only
>> called from bond_handle_frame(), which is rx_handler and always called
>> under rcu from __netif_receive_skb_core() ).
>>
>> The slave active/passive and/or bonding params can change in-flight, however
>> we don't really care about that - we only modify the last time packet was
>> received, which is harmless.
>>
>> CC: Jay Vosburgh <fubar@us.ibm.com>
>> CC: Andy Gospodarek <andy@greyhouse.net>
>> Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
>> ---
>>  drivers/net/bonding/bond_main.c | 3 ---
>>  1 file changed, 3 deletions(-)
>>
>> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>> index 3bce855..3c50bec 100644
>> --- a/drivers/net/bonding/bond_main.c
>> +++ b/drivers/net/bonding/bond_main.c
>> @@ -2260,8 +2260,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
>>  	if (skb->protocol != __cpu_to_be16(ETH_P_ARP))
>>  		return RX_HANDLER_ANOTHER;
>>
>> -	read_lock(&bond->lock);
>> -
>>  	if (!slave_do_arp_validate(bond, slave))
>>  		goto out_unlock;
>>
>> @@ -2318,7 +2316,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
>>  		bond_validate_arp(bond, slave, tip, sip);
>>
>>  out_unlock:
>> -	read_unlock(&bond->lock);
>>  	if (arp != (struct arphdr *)skb->data)
>>  		kfree(arp);
>>  	return RX_HANDLER_ANOTHER;
>>
>
>I think it is not enough, you should add rcu_dereference for bond->curr_active_slave, it may be changed during
>the recv processing.

bond->lock has absolutely nothing to du with bond->curr_active_slave .

>
>Regards
>Ding
>
>

Re: [PATCH v4 net-next 02/12] bonding: permit using arp_validate with non-ab modes

[Veaceslav Falico]

On Mon, Feb 17, 2014 at 04:22:21PM +0100, Nikolay Aleksandrov wrote:
>On 02/17/2014 03:41 PM, Veaceslav Falico wrote:
>> Currently it's disabled because it's sometimes hard, in typical configs, to
>> make it work - because of the nature how the loadbalance modes work - as
>> it's hard to deliver valid arp replies to correct slaves by the switch.
>>
>> However we still can use arp_validation in loadbalance with several other
>> configs, per example with arp_validate == 2 for backup with one broadcast
>> domain, without the switch(es) doing any balancing - this way we'd be (a
>> bit more) sure that the slave is up.
>>
>> So, enable it to let users decide which one works/suits them best. Also
>> remove the mode limitation from BOND_OPT_ARP_VALIDATE.
>>
>> CC: Jay Vosburgh <fubar@us.ibm.com>
>> CC: Andy Gospodarek <andy@greyhouse.net>
>> Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
>> ---
>>  Documentation/networking/bonding.txt | 6 +++---
>>  drivers/net/bonding/bond_main.c      | 4 ----
>>  drivers/net/bonding/bond_options.c   | 1 -
>>  3 files changed, 3 insertions(+), 8 deletions(-)
>>
>> diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt
>> index 5cdb229..96b4ad8 100644
>> --- a/Documentation/networking/bonding.txt
>> +++ b/Documentation/networking/bonding.txt
>> @@ -270,9 +270,9 @@ arp_ip_target
>>  arp_validate
>>
>>  	Specifies whether or not ARP probes and replies should be
>> -	validated in the active-backup mode.  This causes the ARP
>> -	monitor to examine the incoming ARP requests and replies, and
>> -	only consider a slave to be up if it is receiving the
>> +	validated in any mode that supports arp monitoring.  This causes
>> +	the ARP monitor to examine the incoming ARP requests and replies,
>> +	and only consider a slave to be up if it is receiving the
>>  	appropriate ARP traffic.
>>
>>  	Possible values are:
>> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>> index 3c50bec..91c0248 100644
>> --- a/drivers/net/bonding/bond_main.c
>> +++ b/drivers/net/bonding/bond_main.c
>> @@ -4183,10 +4183,6 @@ static int bond_check_params(struct bond_params *params)
>>  	}
>>
>>  	if (arp_validate) {
>> -		if (bond_mode != BOND_MODE_ACTIVEBACKUP) {
>> -			pr_err("arp_validate only supported in active-backup mode\n");
>> -			return -EINVAL;
>> -		}
>>  		if (!arp_interval) {
>>  			pr_err("arp_validate requires arp_interval\n");
>>  			return -EINVAL;
>> diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
>> index f3eb44d..d566cab 100644
>> --- a/drivers/net/bonding/bond_options.c
>> +++ b/drivers/net/bonding/bond_options.c
>> @@ -151,7 +151,6 @@ static struct bond_option bond_opts[] = {
>>  		.id = BOND_OPT_ARP_VALIDATE,
>>  		.name = "arp_validate",
>>  		.desc = "validate src/dst of ARP probes",
>> -		.unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_ACTIVEBACKUP)),
>>  		.values = bond_arp_validate_tbl,
>>  		.set = bond_option_arp_validate_set
>>  	},
>>
>Sorry for not noticing before, but I just remembered the reason why all the
>checks are there when changing the recv_probe, especially from the options.
>The problem was that lacp mode also uses the recv_probe, so after this patch we
>can overwrite the recv_probe while it's running in lacp mode, because
>bond_option_arp_validate_set changes the recv_probe. We can actually only set it
>to NULL because arp_interval can't be set in those modes, but still we can break
>the mode and there'll be need for at least down/up cycle to fix it.
>I think rlb also uses the recv_probe so this applies to it as well.

Yep, missed that too, thanks a lot Nik. It should just be the same as for
BOND_OPT_ARP_INTERVAL:

  177                 .unsuppmodes = BIT(BOND_MODE_8023AD) | BIT(BOND_MODE_TLB) |
  178                                BIT(BOND_MODE_ALB),

which makes sense - as in those modes it's indeed more than useless.

I'll change it and send v5.

>
>Nik
>

Re: [PATCH v4 net-next 01/12] bonding: remove bond->lock from bond_arp_rcv

[Ding Tianhong]

On 2014/2/18 14:12, Veaceslav Falico wrote:
> On Tue, Feb 18, 2014 at 12:02:41PM +0800, Ding Tianhong wrote:
>> On 2014/2/17 22:41, Veaceslav Falico wrote:
>>> We're always called with rcu_read_lock() held (bond_arp_rcv() is only
>>> called from bond_handle_frame(), which is rx_handler and always called
>>> under rcu from __netif_receive_skb_core() ).
>>>
>>> The slave active/passive and/or bonding params can change in-flight, however
>>> we don't really care about that - we only modify the last time packet was
>>> received, which is harmless.
>>>
>>> CC: Jay Vosburgh <fubar@us.ibm.com>
>>> CC: Andy Gospodarek <andy@greyhouse.net>
>>> Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
>>> ---
>>>  drivers/net/bonding/bond_main.c | 3 ---
>>>  1 file changed, 3 deletions(-)
>>>
>>> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>>> index 3bce855..3c50bec 100644
>>> --- a/drivers/net/bonding/bond_main.c
>>> +++ b/drivers/net/bonding/bond_main.c
>>> @@ -2260,8 +2260,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
>>>      if (skb->protocol != __cpu_to_be16(ETH_P_ARP))
>>>          return RX_HANDLER_ANOTHER;
>>>
>>> -    read_lock(&bond->lock);
>>> -
>>>      if (!slave_do_arp_validate(bond, slave))
>>>          goto out_unlock;
>>>
>>> @@ -2318,7 +2316,6 @@ int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
>>>          bond_validate_arp(bond, slave, tip, sip);
>>>
>>>  out_unlock:
>>> -    read_unlock(&bond->lock);
>>>      if (arp != (struct arphdr *)skb->data)
>>>          kfree(arp);
>>>      return RX_HANDLER_ANOTHER;
>>>
>>
>> I think it is not enough, you should add rcu_dereference for bond->curr_active_slave, it may be changed during
>> the recv processing.
> 
> bond->lock has absolutely nothing to du with bond->curr_active_slave .
> 
Yep, this problem is introduced by commit aeea64ac7， there is no way to protect the curr_active_slave, so
I think you could fix it in this patch together.
 
	else if (bond->curr_active_slave &&
		 time_after(slave_last_rx(bond, bond->curr_active_slave),
			    bond->curr_active_slave->jiffies))
>>
>> Regards
>> Ding
>>
>>
> 
> 

Re: [PATCH v4 net-next 01/12] bonding: remove bond->lock from bond_arp_rcv

[Veaceslav Falico]

On Tue, Feb 18, 2014 at 03:07:46PM +0800, Ding Tianhong wrote:
>On 2014/2/18 14:12, Veaceslav Falico wrote:
>> On Tue, Feb 18, 2014 at 12:02:41PM +0800, Ding Tianhong wrote:
>>> On 2014/2/17 22:41, Veaceslav Falico wrote:
...snip...
>>> I think it is not enough, you should add rcu_dereference for bond->curr_active_slave, it may be changed during
>>> the recv processing.
>>
>> bond->lock has absolutely nothing to du with bond->curr_active_slave .
>>
>Yep, this problem is introduced by commit aeea64ac7， there is no way to protect the curr_active_slave, so
>I think you could fix it in this patch together.
>
>	else if (bond->curr_active_slave &&
>		 time_after(slave_last_rx(bond, bond->curr_active_slave),
>			    bond->curr_active_slave->jiffies))

It's not related to this patchset, but yeah, I'll send a fix afterwards.

>>>
>>> Regards
>>> Ding
>>>
>>>
>>
>>
>
>