29/09/2020 12:26, Maxime Coquelin: > On 9/29/20 1:14 AM, Thomas Monjalon wrote: > > The function rte_eth_dev_release_port() was resetting partially > > the struct rte_eth_dev. The drivers were completing it > > with more pointers set to NULL in the close or remove operations. > > > > A full memset is done so most of those assignments become useless. [...] > With this patch, I get following segfault at init time with Virtio PMD: > > Program received signal SIGSEGV, Segmentation fault. > 0x0000000000854c9b in rte_eth_dev_callback_register (port_id=32, > event=RTE_ETH_EVENT_UNKNOWN, cb_fn=0x4b24de > <eth_event_callback>, > cb_arg=0x0) at ../lib/librte_ethdev/rte_ethdev.c:4042 > 4042 > TAILQ_INSERT_TAIL(&(dev->link_intr_cbs),
Yes this is because after closing a port, everything is resetted, including .link_intr_cbs which is set only once in a constructor: http://git.dpdk.org/dpdk/commit/?id=9ec0b3869d8 I can change this patch to selectively set pointers to NULL. Or if we prefer a big memset 0, we need to rework how RTE_ETH_ALL is managed to register a callback for any event. Instead of setting the callback for all ports, we could have a special catch-call callback list which is called for all events. This way we could revert initializing .link_intr_cbs in eth_dev_get().