Re: e1000_intr in request_irq faults in 2.6.20-git

[Auke Kok <auke-jan.h.kok@intel.com>]

[Adding Dimitri Mishin to the CC - he proposed the same patch earlier]

Len Brown wrote:
> On Thursday 15 February 2007 21:10, Brandeburg, Jesse wrote:
>> Eric W. Biederman wrote:
>>> Len Brown <lenb@kernel.org> writes:
>>>
>>>> e1000 faults in 2.6.20-git, while 2.6.20 worked fine.
>>>>
>>>> System is a D875PBZ with LOM.
>>>>
>>>> clues?
>>> I'm guessing this is an old bug found by the following bit of
>>> debug coded added into since v2.6.20
>>>
>>> +#ifdef CONFIG_DEBUG_SHIRQ
>>> +       if (irqflags & IRQF_SHARED) {
>>> +               /*
>>> +                * It's a shared IRQ -- the driver ought to be
>>> prepared for it +                * to happen immediately, so let's
>>> make sure.... +                * We do this before actually
>>> registering it, to make sure that +                * a 'real' IRQ
>>> doesn't run in parallel with our fake +                */
>>> +               if (irqflags & IRQF_DISABLED) {
>>> +                       unsigned long flags;
>>> +
>>> +                       local_irq_save(flags);
>>> +                       handler(irq, dev_id);
>>> +                       local_irq_restore(flags);
>>> +               } else
>>> +                       handler(irq, dev_id);
>>> +       }
>>> +#endif
>>>
>>> I don't have a clue why the e1000 wasn't ready though.
>>>
>> our code is clearly calling request_irq before we have assigned the
>> function pointer adapter->clean_rx as well as adapter->alloc_rx_buf
>>
>> That would be a bug, a possible patch would be (inline and attached):
>> compile tested, *but* I couldn't test this patch to make sure it worked
>> because I couldn't boot 2.6.20-git due to it not finding my RAID0 + lvm
>> disk.
>>
>> [PATCH] e1000: fix shared interrupt warning message
>>
>> From: Jesse Brandeburg <jesse.brandeburg@intel.com>
>>
>> Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
>> ---
>>
>>  drivers/net/e1000/e1000_main.c |   13 +++++++------
>>  1 files changed, 7 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/net/e1000/e1000_main.c
>> b/drivers/net/e1000/e1000_main.c
>> index 619c892..b8c4d5c 100644
>> --- a/drivers/net/e1000/e1000_main.c
>> +++ b/drivers/net/e1000/e1000_main.c
>> @@ -1417,10 +1417,6 @@ e1000_open(struct net_device *netdev)
>>         if ((err = e1000_setup_all_rx_resources(adapter)))
>>                 goto err_setup_rx;
>>
>> -       err = e1000_request_irq(adapter);
>> -       if (err)
>> -               goto err_req_irq;
>> -
>>         e1000_power_up_phy(adapter);
>>
>>         if ((err = e1000_up(adapter)))
>> @@ -1431,6 +1427,10 @@ e1000_open(struct net_device *netdev)
>>                 e1000_update_mng_vlan(adapter);
>>         }
>>
>> +       err = e1000_request_irq(adapter);
>> +       if (err)
>> +               goto err_req_irq;
>> +
>>         /* If AMT is enabled, let the firmware know that the network
>>          * interface is now open */
>>         if (adapter->hw.mac_type == e1000_82573 &&
>> @@ -1439,10 +1439,11 @@ e1000_open(struct net_device *netdev)
>>
>>         return E1000_SUCCESS;
>>
>> +err_req_irq:
>> +       e1000_down(adapter);
>> +       e1000_free_irq(adapter);
>>  err_up:
>>         e1000_power_down_phy(adapter);
>> -       e1000_free_irq(adapter);
>> -err_req_irq:
>>         e1000_free_all_rx_resources(adapter);
>>  err_setup_rx:
>>         e1000_free_all_tx_resources(adapter);
>>
> 
> Works for me(tm) on latest 2.6.20-git and D875PBZ.


If there are no objections I'll push this patch to Jeff Garzik together with two 
other changes I have for him.

Cheers,

Auke