Hi Hao
On 10/25/22 08:19, Hao Chen wrote:
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
NG == not good? Please don't use abbreviations.
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.
I'm wondering whether the flag shouldn't just be set by default, as the
feature negotiation will be done between the vDPA driver & the guest
driver anyways?
Signed-off-by: Hao Chen <ch...@yusur.tech>
---
v3:
*Modify mail title.
v2:
*fprintf all string including the eal one.
*remove exit(1).
examples/vdpa/main.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/examples/vdpa/main.c b/examples/vdpa/main.c
index 4c7e81d7b6..71149461c6 100644
--- a/examples/vdpa/main.c
+++ b/examples/vdpa/main.c
@@ -43,16 +43,18 @@ 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);
+ 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, "Usage: %s [EAL options] --\n%s", prgname, usage_str);
}
static int
@@ -63,6 +65,7 @@ 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 +223,10 @@ 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,