[dpdk-dev] [PATCH 4/6] examples/ntb: enable an example for ntb

Ye Xiaolong xiaolong.ye at intel.com
Thu Jun 6 04:07:46 CEST 2019


On 06/05, Li, Xiaoyun wrote:
>> 
>> Yes, I agree, but I don't think it is the case here.
>> 
>> >It will cause segment fault in enqueue/dequeue.
>> 
>> Hmm, have you debug it? Which line caused the segfault?
>> 
>> You can refer to test_rawdev_enqdeq function in skeleton_rawdev_test.c, what
>> it does is similar to my suggestion, and you just need one alloc/free.
>> 
>Of course I debug on it. It will cause seg fault at rte_memcpy. Because buffers[0]->buf_addr is not right.
>You can see the debug log.
>(gdb) p test_pkts_send[0].buf_addr
>$3 = (void *) 0x5555562784c0
>(gdb) n
>164             rte_rawdev_set_attr(dev_id, "spad14", val);
>(gdb)
>ntb_attr_set(): Set attribute (spad14) Value (0)
>165             val = size;
>(gdb)
>166             rte_rawdev_set_attr(dev_id, "spad15", val);
>(gdb)
>ntb_attr_set(): Set attribute (spad15) Value (35)
>175             rte_rawdev_enqueue_buffers(dev_id, (struct rte_rawdev_buf **)&test_pkts_send, 1, (void *)size);
>(gdb)
>
>Thread 1 "ntb_fwd" hit Breakpoint 2, ntb_enqueue_bufs (dev=0x555556023b80 <rte_rawdevices>, buffers=0x7fffffff7fe0, count=1,
>    context=0x23) at /home/xiaoyun/ntb/dpdk-next-net-intel/drivers/raw/ntb_rawdev/ntb_rawdev.c:244
>244             struct ntb_hw *hw = dev->dev_private;
>(gdb) n
>248             if (hw->ntb_ops->get_peer_mw_addr == NULL)
>(gdb)
>249                     return -ENOTSUP;
>(gdb) p buffers[0]->buf_addr
>$4 = (void *) 0x6f77206f6c6c6568
>(gdb) p &buffers[0]->buf_addr
>$5 = (void **) 0x5555562784c0

Hmm, you're right, after a second thought, we do need double alloc/free in this
case, my bad.

Thanks,
Xiaolong

>
>> Thanks,
>> Xiaolong
>> 
>> >
>> >I will free twice.
>> >
>> >> > >2.17.1
>> >> > >


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