From: Daniel Borkmann <dan...@iogearbox.net>
There are two issues with the XDP program removal in af_xdp_cleanup():
1) Starting from libxdp 1.3.0 [0] the XDP program gets automatically
detached when we call xsk_socket__delete() for the last successfully
configured queue. libxdp internally keeps track of that. For QEMU
we require libxdp >= 1.4.0. Given QEMU is not loading the program,
lets also not attempt to remove it and delegate this instead.
2) The removal logic is incorrect anyway because we are setting n_queues
into the last queue that never has xdp_flags on failure, so the logic
is always skipped since the non-zero test for s->xdp_flags in
af_xdp_cleanup() fails.
Fixes: cb039ef3d9e3 ("net: add initial support for AF_XDP network backend")
Suggested-by: Ilya Maximets <i.maxim...@ovn.org>
Signed-off-by: Daniel Borkmann <dan...@iogearbox.net>
Reviewed-by: Ilya Maximets <i.maxim...@ovn.org>
Cc: Ilya Maximets <i.maxim...@ovn.org>
Cc: Jason Wang <jasow...@redhat.com>
Cc: Anton Protopopov <as...@isovalent.com>
Link:
https://github.com/xdp-project/xdp-tools/commit/38c2914988fd5c1ef65f2381fc8af9f3e8404e2b
[0]
Signed-off-by: Jason Wang <jasow...@redhat.com>
---
net/af-xdp.c | 12 ------------
1 file changed, 12 deletions(-)
diff --git a/net/af-xdp.c b/net/af-xdp.c
index d022534d76..3d3268e18b 100644
--- a/net/af-xdp.c
+++ b/net/af-xdp.c
@@ -49,7 +49,6 @@ typedef struct AFXDPState {
char *buffer;
struct xsk_umem *umem;
- uint32_t n_queues;
uint32_t xdp_flags;
bool inhibit;
} AFXDPState;
@@ -274,14 +273,6 @@ static void af_xdp_cleanup(NetClientState *nc)
s->umem = NULL;
qemu_vfree(s->buffer);
s->buffer = NULL;
-
- /* Remove the program if it's the last open queue. */
- if (!s->inhibit && nc->queue_index == s->n_queues - 1 && s->xdp_flags
- && bpf_xdp_detach(s->ifindex, s->xdp_flags, NULL) != 0) {
- fprintf(stderr,
- "af-xdp: unable to remove XDP program from '%s', ifindex:
%d\n",
- s->ifname, s->ifindex);
- }
}
static int af_xdp_umem_create(AFXDPState *s, int sock_fd, Error **errp)
@@ -490,12 +481,9 @@ int net_init_af_xdp(const Netdev *netdev,
pstrcpy(s->ifname, sizeof(s->ifname), opts->ifname);
s->ifindex = ifindex;
- s->n_queues = queues;
if (af_xdp_umem_create(s, sock_fds ? sock_fds[i] : -1, errp)
|| af_xdp_socket_create(s, opts, errp)) {
- /* Make sure the XDP program will be removed. */
- s->n_queues = i;
error_propagate(errp, err);
goto err;
}
--
2.42.0
