Subject: [RFC] mark devices with broken LRO implementation

From: Stephen Hemminger <[email-masked]>
Date: Mon, 6 Dec 2010 09:10:10 -0800

The kernel uses dev_disable_lro to disable Large Receive Offload
for cases where it is inappropriate. But several drivers do not implement
the required hook.  This is a "penalty box" patch to encourage those
drivers to add support for the necessary ethtool set_flags.

Signed-off-by: Stephen Hemminger <[email-masked]>
---
I only found three drivers that are broken. Normally, I would just fix
them; but since changing state in the device is hardware specific, and
I don't have the hardware or specs to do anything useful to fix it.

--- a/drivers/net/Kconfig	2010-12-06 08:52:30.376926696 -0800
+++ b/drivers/net/Kconfig	2010-12-06 09:02:02.013224592 -0800
@@ -28,6 +28,13 @@ menuconfig NETDEVICES
 # that for each of the symbols.
 if NETDEVICES
 
+config BROKEN_LRO
+       bool
+       ---help---
+         Allow drivers with partial Large Receive Offload support. These drivers
+	 do not implement the necessary feature of disabling LRO support via
+	 the ethtool set_flags operation.
+
 config IFB
 	tristate "Intermediate Functional Block support"
 	depends on NET_CLS_ACT
@@ -2675,7 +2682,7 @@ config CHELSIO_T4VF
 
 config EHEA
 	tristate "eHEA Ethernet support"
-	depends on IBMEBUS && INET && SPARSEMEM
+	depends on IBMEBUS && INET && SPARSEMEM && BROKEN_LRO
 	select INET_LRO
 	---help---
 	  This driver supports the IBM pSeries eHEA ethernet adapter.
@@ -2848,7 +2855,7 @@ config NIU
 
 config PASEMI_MAC
 	tristate "PA Semi 1/10Gbit MAC"
-	depends on PPC_PASEMI && PCI && INET
+	depends on PPC_PASEMI && PCI && INET && BROKEN_LRO
 	select PHYLIB
 	select INET_LRO
 	help
@@ -2857,7 +2864,7 @@ config PASEMI_MAC
 
 config MLX4_EN
 	tristate "Mellanox Technologies 10Gbit Ethernet support"
-	depends on PCI && INET
+	depends on PCI && INET && BROKEN_LRO
 	select MLX4_CORE
 	select INET_LRO
 	help