On 05/03/15 13:18, Ben Hutchings wrote:

On Thu, 2015-03-05 at 10:02 +0100, Geert Uytterhoeven wrote:

quoted

Replying to a patchwork mbox, as I noticed this is in net-next.

On Thu, 26 Feb 2015, Ben Hutchings wrote:

quoted

Currently we may silently read/write a register at offset 0.  Change
this to WARN and then ignore the write or read-back all-ones.

Signed-off-by: Ben Hutchings <redacted>
Acked-by: Sergei Shtylyov <redacted>

While this may be a good idea for debugging...

quoted

--- a/drivers/net/ethernet/renesas/sh_eth.h
+++ b/drivers/net/ethernet/renesas/sh_eth.h

@@ -543,19 +543,29 @@ static inline void sh_eth_soft_swap(char *src, int len)
 #endif
 }
 
+#define SH_ETH_OFFSET_INVALID	((u16) ~0)
+
 static inline void sh_eth_write(struct net_device *ndev, u32 data,
 				int enum_index)
 {
 	struct sh_eth_private *mdp = netdev_priv(ndev);

does de-referencing this each time make a difference? Looks like
it would have been easier to pass an "struct sh_eth_private" instead
of the "struct net_device *ndev"

quoted

quoted

+	u16 offset = mdp->reg_offset[enum_index];
+
+	if (WARN_ON(offset == SH_ETH_OFFSET_INVALID))
+		return;

You could cange the mdp->reg_offset to an mdp->reg_pointer and make
any invalid registers a NULL. This would at-least make it fail on an
invalid access.

quoted

... adding WARN_ON() to static inline functions increases code size a lot:

$ size drivers/net/ethernet/renesas/sh_eth.o{.orig,}
   text	   data	    bss	    dec	    hex	filename
  23352	   1136	      0	  24488	   5fa8	drivers/net/ethernet/renesas/sh_eth.o.orig
  27225	   1136	      0	  28361	   6ec9	drivers/net/ethernet/renesas/sh_eth.o
$

Time to un-inline it, maybe?

Ben.


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Ben Dooks				http://www.codethink.co.uk/
Senior Engineer				Codethink - Providing Genius