[bug report] nvme sends invalid command capsule over rdma transport for 5KiB write when target supports MSDBD > 1

[Max Gurtovoy]

On 5/26/2021 5:10 PM, Christoph Hellwig wrote:
> On Wed, May 26, 2021 at 02:12:08AM -0700, Sagi Grimberg wrote:
>>   {
>> -       struct nvme_sgl_desc *sg = &c->common.dptr.sgl;
>> -       struct scatterlist *sgl = req->data_sgl.sg_table.sgl;
>> +       struct nvme_sgl_desc *sgl = &c->common.dptr.sgl;
>> +       struct scatterlist *sg, *scat = req->data_sgl.sg_table.sgl;
>>          struct ib_sge *sge = &req->sge[1];
>>          u32 len = 0;
>>          int i;
>>
>> -       for (i = 0; i < count; i++, sgl++, sge++) {
>> -               sge->addr = sg_dma_address(sgl);
>> -               sge->length = sg_dma_len(sgl);
>> +       for_each_sg(scat, sg, count, i) {
>> +               sge->addr = sg_dma_address(sg);
>> +               sge->length = sg_dma_len(sg);
>>                  sge->lkey = queue->device->pd->local_dma_lkey;
>>                  len += sge->length;
>>          }
> We do need for_each_sg here indeed, but you also need to keep
> incrementing sge for each loop iteration.  I think we can also
> drop the scat local variable with just a single users and all the
> renaming while we're at it.

Is the above fixing the issue ?

Seems like code refactoring to me, right ?