Re: [PATCH v3 ipsec-next 3/3] xfrm: wrap xfrmdev_ops with offload config

On 12/20/2017 8:03 AM, Marcelo Ricardo Leitner wrote:

On Tue, Dec 19, 2017 at 03:35:49PM -0800, Shannon Nelson wrote:

quoted

There's no reason to define netdev->xfrmdev_ops if
the offload facility is not CONFIG'd in.

Signed-off-by: Shannon Nelson <redacted>

This one could use a Fixes tag perhaps:
Fixes: d77e38e612a0 ("xfrm: Add an IPsec hardware offloading API")

as in theory the build was broken since then, as it added:
+#ifdef CONFIG_XFRM_OFFLOAD
+struct xfrmdev_ops {
...
+#ifdef CONFIG_XFRM
+       const struct xfrmdev_ops *xfrmdev_ops;

So the pointer would have an undefined type
   if CONFIG_XFRM && !CONFIG_XFRM_OFFLOAD
Though I couldn't reproduce this, not sure why.

Hmmm, I don't think this requires a "Fixes" tag, as the code all worked just fine, I'm just doing a little cleaning.

Patch 2/3 adds a more intense look at the data structure, so I needed to change it to the CONFIG_XFRM_OFFLOAD so as to not break the build. Since the xfrmdev_ops field is now never used unless we have CONFIG_XFRM_OFFLOAD, we can change the net_device definition to be just a bit smaller without it.

But.. is it buildable with this patch? I mine failed:

obj-$(CONFIG_XFRM) := xfrm_policy.o xfrm_state.o xfrm_hash.o \
                       xfrm_input.o xfrm_output.o \
                       xfrm_sysctl.o xfrm_replay.o xfrm_device.o

so xfrm_device is always in if CONFIG_XFRM is there,
xfrm_dev_init(), via xfrm_dev_notifier -> xfrm_dev_event() ->
   xfrm_dev_register() and then:

static int xfrm_dev_register(struct net_device *dev)
{
         if ((dev->features & NETIF_F_HW_ESP) && !dev->xfrmdev_ops)

This looks like you haven't applied version 3 of the 2nd patch "xfrm: check for xdo_dev_ops add and delete".  I missed this in the earlier version (not enough compile tests), but version 3 of patch 2/3  should address it.

sln

                                                  ^^^^^^^^^^^^^^^^

We can't control CONFIG_XFRM_OFFLOAD directly, so unless you
unselected other offloadings such as INET_ESP_OFFLOAD, it is still on.

linux/net/xfrm/xfrm_device.c: In function ‘xfrm_dev_register’:
linux/net/xfrm/xfrm_device.c:147:48: error: ‘struct net_device’ has no member named ‘xfrmdev_ops’; did you mean ‘netdev_ops’?
   if ((dev->features & NETIF_F_HW_ESP) && !dev->xfrmdev_ops)
                                                 ^~~~~~~~~~~
                                                 netdev_ops

quoted

---
  include/linux/netdevice.h | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 2eaac7d..145d0de 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h

@@ -1697,7 +1697,7 @@ struct net_device {
  	const struct ndisc_ops *ndisc_ops;
  #endif
  
-#ifdef CONFIG_XFRM
+#ifdef CONFIG_XFRM_OFFLOAD
  	const struct xfrmdev_ops *xfrmdev_ops;
  #endif
  

-- 
2.7.4