On 4/28/20 10:35 AM, Thomas Falcon wrote:
> On 4/27/20 12:33 PM, Juliet Kim wrote:
>> The maximum entries for H_SEND_SUB_CRQ_INDIRECT has increased on
>> some platforms from 16 to 128. If Live Partition Mobility is used
>> to migrate a running OS image from a newer source platform to an
>> older target platform, then H_SEND_SUB_CRQ_INDIRECT will fail with
>> H_PARAMETER if 128 entries are queued.
>>
>> Fix this by falling back to 16 entries if H_PARAMETER is returned
>> from the hcall().
>
> Thanks for the submission, but I am having a hard time believing that this is
> what is happening since the driver does not support sending multiple frames
> per hypervisor call at this time. Even if it were the case, this approach
> would omit frame data needed by the VF, so the second attempt may still fail.
> Are there system logs available that show the driver is attempting to send
> transmissions with greater than 16 descriptors?
>
> Thanks,
>
> Tom
>
>
I am trying to confirm.
Juliet
>>
>> Signed-off-by: Juliet Kim <juli...@linux.vnet.ibm.com>
>> ---
>> drivers/net/ethernet/ibm/ibmvnic.c | 11 +++++++++++
>> 1 file changed, 11 insertions(+)
>>
>> diff --git a/drivers/net/ethernet/ibm/ibmvnic.c
>> b/drivers/net/ethernet/ibm/ibmvnic.c
>> index 4bd33245bad6..b66c2f26a427 100644
>> --- a/drivers/net/ethernet/ibm/ibmvnic.c
>> +++ b/drivers/net/ethernet/ibm/ibmvnic.c
>> @@ -1656,6 +1656,17 @@ static netdev_tx_t ibmvnic_xmit(struct sk_buff *skb,
>> struct net_device *netdev)
>> lpar_rc = send_subcrq_indirect(adapter, handle_array[queue_num],
>> (u64)tx_buff->indir_dma,
>> (u64)num_entries);
>> +
>> + /* Old firmware accepts max 16 num_entries */
>> + if (lpar_rc == H_PARAMETER && num_entries > 16) {
>> + tx_crq.v1.n_crq_elem = 16;
>> + tx_buff->num_entries = 16;
>> + lpar_rc = send_subcrq_indirect(adapter,
>> + handle_array[queue_num],
>> + (u64)tx_buff->indir_dma,
>> + 16);
>> + }
>> +
>> dma_unmap_single(dev, tx_buff->indir_dma,
>> sizeof(tx_buff->indir_arr), DMA_TO_DEVICE);
>> } else {
