[PATCH v2] net: mvmdio: fix interrupt timeout handling

[Leigh Brown]

On 2013-12-19 17:43, Jason Gunthorpe wrote:
> On Thu, Dec 19, 2013 at 01:09:48PM +0000, Leigh Brown wrote:
>> This version corrects the whitespace issue.
>> 
>> orion_mdio_wait_ready uses wait_event_timeout to wait for the
>> SMI interrupt to fire.  wait_event_timeout waits for between
>> "timeout - 1" and "timeout" jiffies.  In this case a 1ms timeout
>> when HZ is 1000 results in a wait of 0 to 1 jiffies, causing
>> premature timeouts.
>> 
>> This fix ensures a minimum timeout of 2 jiffies, ensuring
>> wait_event_timeout will always wait at least 1 jiffie.
>> 
>> Issue reported by Nicolas Schichan.
>> 
>> Tested-by: Nicolas Schichan <nschichan at freebox.fr>
>> Signed-off-by: Leigh Brown <leigh at solinno.co.uk>
>>  drivers/net/ethernet/marvell/mvmdio.c | 6 ++++++
>>  1 file changed, 6 insertions(+)
> 
> Leigh, I have just noticed a regression in 3.13-rc3 vs 3.10, on
> kirkwood where 3.13 occasionally prints:
> 
> 3 12/11 13:59:02 kernel: orion-mdio f1072004.mdio: Timeout: SMI busy
> for too long
> 
> Is that the same issue that this patch is addressing?

Yes, absolutely.

Regards,

Leigh.