Re: [PATCH net-next 1/5] bonding: The fail_over_mac should be set only in ACTIVE_BACKUP mode

[Jay Vosburgh <fubar@us.ibm.com>]

Ding Tianhong <dingtianhong@huawei.com> wrote:

>According the bonding.txt, the option fail_over_mac only affect for
>AB mode, but in currect code, the parameter could be set to active
>or follow in every mode, this will cause bonding could not set all
>slaves of an RR or XOR mode to the same MAC address at enslavement
>time, so reset fail_over_mac to 0 if the mode is not ACTIVE_BACKUP.

	The correct way to fix this in general is to permit setting an
option at any time, but only have it take effect in active-backup mode.
This minimizes ordering requirements when setting options.

	I would instead modify the bond enslave and removal processing
to check the mode in addition to fail_over_mac when setting a slave's
MAC during enslavement.  The change active slave processing already only
calls the fail_over_mac function when in active-backup mode.  This
should also be a simpler change set.

>Fix the wrong variables for pr_err().
>
>Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
>---
> drivers/net/bonding/bond_main.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>index 3220b48..ecff04e 100644
>--- a/drivers/net/bonding/bond_main.c
>+++ b/drivers/net/bonding/bond_main.c
>@@ -4307,12 +4307,14 @@ static int bond_check_params(struct bond_params *params)
> 						      fail_over_mac_tbl);
> 		if (fail_over_mac_value == -1) {
> 			pr_err("Error: invalid fail_over_mac \"%s\"\n",
>-			       arp_validate == NULL ? "NULL" : arp_validate);
>+			       fail_over_mac == NULL ? "NULL" : fail_over_mac);

	This part is ok.

> 			return -EINVAL;
> 		}
>
>-		if (bond_mode != BOND_MODE_ACTIVEBACKUP)
>-			pr_warning("Warning: fail_over_mac only affects active-backup mode.\n");
>+		if (bond_mode != BOND_MODE_ACTIVEBACKUP) {
>+			pr_warning("Warning: fail_over_mac only affects active-backup mode, set it to 0.\n");
>+			fail_over_mac_value = BOND_FOM_NONE;
>+		}

	This part is not.

	I would additionally NAK patches 2, 3, and 4 (noting that 4
inhibits the change to fail_over_mac, but not the warning message that
we're changing it).

	Patch 5 is ok, although it really has nothing to do with
fail_over_mac.

	-J

> 	} else {
> 		fail_over_mac_value = BOND_FOM_NONE;
> 	}
>-- 
>1.8.0

---
	-Jay Vosburgh, IBM Linux Technology Center, fubar@us.ibm.com