I found this meaning in DPDK testplan.
Note that currently hot-plugging of representor ports is not supported so all
the required representors must be specified on the creation of the PF or the
trusted VF.
When testpmd is started with pf and vf representors, the order of representor
is determined on creation. So it is guaranteed that ,pf is beneath the vf
representors, we implemented in a reverse way is acceptable just at present,
depends on when the hot-plugging of representor is supported.
> -----Original Message-----
> From: Wu, WenxuanX <wenxuanx...@intel.com>
> Sent: 2022年2月23日 19:33
> To: Li, Xiaoyun <xiaoyun...@intel.com>; Yigit, Ferruh
> <ferruh.yi...@intel.com>; dev@dpdk.org
> Cc: Wu, WenxuanX <wenxuanx...@intel.com>; sta...@dpdk.org
> Subject: [PATCH v2 2/2] app/testpmd:fix testpmd quit failure
>
> From: wenxuan wu <wenxuanx...@intel.com>
>
> When testpmd start ed with 1 pf and 2 vfs, testpmd quited while vfs were
> still alive would result in failure. Root cause is that pf had been released
> already but vfs were still accessing by func rte_eth_dev_info_get, which
> would result in heap-free-after-use error.
>
> By quitting our ports in reverse order to avoid this.And the order is
> guaranteed that vf are created after pfs.
>
> Fixes: d3a274ce9dee ("app/testpmd: handle SIGINT and SIGTERM")
> Cc: sta...@dpdk.org
>
> Signed-off-by: wenxuan wu <wenxuanx...@intel.com>
> ---
> app/test-pmd/testpmd.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c index
> e1da961311..698b6d8cc4 100644
> --- a/app/test-pmd/testpmd.c
> +++ b/app/test-pmd/testpmd.c
> @@ -3384,12 +3384,12 @@ pmd_test_exit(void) #endif
> if (ports != NULL) {
> no_link_check = 1;
> - RTE_ETH_FOREACH_DEV(pt_id) {
> + RTE_ETH_FOREACH_DEV_REVERSE(pt_id) {
> printf("\nStopping port %d...\n", pt_id);
> fflush(stdout);
> stop_port(pt_id);
> }
> - RTE_ETH_FOREACH_DEV(pt_id) {
> + RTE_ETH_FOREACH_DEV_REVERSE(pt_id) {
> printf("\nShutting down port %d...\n", pt_id);
> fflush(stdout);
> close_port(pt_id);
> --
> 2.25.1
