[dpdk-dev] [PATCH] fix for 2 consecutive rte_eth_dev_start() can cause a SIGSEGV

[Ananyev, Konstantin]

Hi Thomas,

>> 1)If igb_alloc_rx_queue_mbufs() would fail to allocate an mbuf for RX queue,
>> it calls igb_rx_queue_release(rxq).
>> That causes rxq to be silently freed, without updating 
>> dev->data->rx_queues[]. So any firther reference to it will trigger the
>> SIGSEGV.
>> Same thing in em PMD too.
>> To fix: igb_alloc_rx_queue_mbufs() should just return an error to the caller
>> and let upper layer to deal with the probem.
>> That's what ixgbe PMD doing right now.
>> 2)In tx_queue_setup (for all 3 PMDs: ixgbe, igb, em) we call
>> tx_queue_release(dev->data->tx_queues[queue_idx])
>> without setting dev->data->tx_queues[queue_idx] = NULL
>> afterwards.
>> 3)Prevent rte_eth_dev_start/stop to call underneath dev_start/dev_stop
>> for already started/stopped device.
>> 4) fix compiler warning on PMD_DEBUG_TRACE() formats.

>Please, only 1 fix per patch.
>This way, we'll hopefully have a nice title for each fix.
>It's simpler for changelog.

It is all fix for the same problem (except #4 of course).
I just put 1,2,3 to make it clear from what sub-parts fix consists.

Konstantin