Re: [PATCH v3] igb: Allocate MSI-X vector when testing

Akihiko Odaki
2022-11-25T09:51:32Z

On 2022/11/24 0:41, Maciej Fijalkowski wrote:
> On Wed, Nov 23, 2022 at 10:09:26AM +0900, Akihiko Odaki wrote:
>> Without this change, the interrupt test fail with MSI-X environment:
>>
>> $ sudo ethtool -t enp0s2 offline
>> [ 43.921783] igb 0000:00:02.0: offline testing starting
>> [ 44.855824] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Down
>> [ 44.961249] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
>> [ 51.272202] igb 0000:00:02.0: testing shared interrupt
>> [ 56.996975] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
>> The test result is FAIL
>> The test extra info:
>> Register test (offline) 0
>> Eeprom test (offline) 0
>> Interrupt test (offline) 4
>> Loopback test (offline) 0
>> Link test (on/offline) 0
>>
>> Here, "4" means an expected interrupt was not delivered.
>>
>> To fix this, route IRQs correctly to the first MSI-X vector by setting
>> IVAR_MISC. Also, set bit 0 of EIMS so that the vector will not be
>> masked. The interrupt test now runs properly with this change:
>
> Much better!
>
>>
>> $ sudo ethtool -t enp0s2 offline
>> [ 42.762985] igb 0000:00:02.0: offline testing starting
>> [ 50.141967] igb 0000:00:02.0: testing shared interrupt
>> [ 56.163957] igb 0000:00:02.0 enp0s2: igb: enp0s2 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
>> The test result is PASS
>> The test extra info:
>> Register test (offline) 0
>> Eeprom test (offline) 0
>> Interrupt test (offline) 0
>> Loopback test (offline) 0
>> Link test (on/offline) 0
>>
>> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
>
> Same comment as on other patch - justify why there is no fixes tag and
> specify the tree in subject.

I couldn't identify what commit introduced the problem. Please see:
https://lore.kernel.org/netdev/f2457229-865a-57a0-94a1-c5c63b2f30a5@daynix.com/

Regards,
Akihiko Odaki

>
>> ---
>> drivers/net/ethernet/intel/igb/igb_ethtool.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c
>> index e5f3e7680dc6..ff911af16a4b 100644
>> --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
>> +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
>> @@ -1413,6 +1413,8 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data)
>> *data = 1;
>> return -1;
>> }
>> + wr32(E1000_IVAR_MISC, E1000_IVAR_VALID << 8);
>> + wr32(E1000_EIMS, BIT(0));
>> } else if (adapter->flags & IGB_FLAG_HAS_MSI) {
>> shared_int = false;
>> if (request_irq(irq,
>> --
>> 2.38.1
>>