> -----Original Message-----
> From: Hao Chen <ch...@yusur.tech>
> Sent: Tuesday, October 11, 2022 10:56 AM
> To: maxime.coque...@redhat.com; Xia, Chenbo <chenbo....@intel.com>
> Cc: dev@dpdk.org; ho...@yusur.tech; z...@yusur.tech
> Subject: [PATCH] example: vdpa: support run in nested virtualization
> environment
Title should be:
examples/vdpa: support running in nested virtualization environment
>
> When we run dpdk vdpa in the nested virtual machine vm-L1 and ping
> test in vm-L2, the ping is NG. The reason for troubleshooting is
> that the virtio net in vm-L2 sends control information to the vring,
> and the qemu back-end device in vm-L1 cannot obtain correct data
> from the vring. This problem is related to the opening of the vIOMMU.
>
> This patch add option '--iommu-support' to use guest vIOMMU to
> protect vhost, then the ping test in vm-L2 is OK.
> This option is required in a nested virtualization environment.
>
> Signed-off-by: Hao Chen <ch...@yusur.tech>
> ---
> examples/vdpa/main.c | 19 ++++++++++++++-----
> 1 file changed, 14 insertions(+), 5 deletions(-)
>
> diff --git a/examples/vdpa/main.c b/examples/vdpa/main.c
> index 4c7e81d7b6..a24c78d7a4 100644
> --- a/examples/vdpa/main.c
> +++ b/examples/vdpa/main.c
> @@ -43,16 +43,20 @@ static char iface[MAX_PATH_LEN];
> static int devcnt;
> static int interactive;
> static int client_mode;
> +static int iommu_support;
>
> /* display usage */
> static void
> vdpa_usage(const char *prgname)
> {
> - printf("Usage: %s [EAL options] -- "
> - " --interactive|-i: run in interactive
> mode.\n"
> - " --iface <path>: specify the path prefix
> of
> the socket files, e.g. /tmp/vhost-user-.\n"
> - " --client: register a vhost-user socket
> as
> client mode.\n",
> - prgname);
> + printf("Usage: %s [EAL options] --\n", prgname);
> + const char *usage_str = " --interactive|-i: run in interactive
> mode.\n"
> + " --iface <path>: specify the path prefix
> of
> the socket files, e.g. /tmp/vhost-user-.\n"
> + " --client: register a vhost-user socket
> as
> client mode.\n"
> + " --iommu-support: use guest vIOMMU to
> protect
> vhost.\n";
> +
> + fprintf(stderr, "%s", usage_str);
Why not use fprintf all string including the eal one?
> + exit(1);
I believe the exit should happen outside of the function.
Thanks,
Chenbo
> }
>
> static int
> @@ -63,6 +67,7 @@ parse_args(int argc, char **argv)
> {"iface", required_argument, NULL, 0},
> {"interactive", no_argument, &interactive, 1},
> {"client", no_argument, &client_mode, 1},
> + {"iommu-support", no_argument, &iommu_support, 1},
> {NULL, 0, 0, 0},
> };
> int opt, idx;
> @@ -220,6 +225,10 @@ start_vdpa(struct vdpa_port *vport)
> socket_path);
> return -1;
> }
> +
> + if (iommu_support)
> + vport->flags |= RTE_VHOST_USER_IOMMU_SUPPORT;
> +
> ret = rte_vhost_driver_register(socket_path, vport->flags);
> if (ret != 0)
> rte_exit(EXIT_FAILURE,
> --
> 2.27.0
