xsk_ring_prod__reserve() doesn't necessarily set idx in some conditions, so
from static analysis point of view compiler is right about the problems like:
In file included from xdpxceiver.c:92:
xdpxceiver.c: In function ‘xsk_populate_fill_ring’:
/data/users/andriin/linux/tools/testing/selftests/bpf/tools/include/bpf/xsk.h:119:20: warning: ‘idx’ may be used uninitialized in this function [-Wmaybe-uninitialized]
return &addrs[idx & fill->mask];
~~~~^~~~~~~~~~~~
xdpxceiver.c:300:6: note: ‘idx’ was declared here
u32 idx;
^~~
xdpxceiver.c: In function ‘tx_only’:
xdpxceiver.c:596:30: warning: ‘idx’ may be used uninitialized in this function [-Wmaybe-uninitialized]
struct xdp_desc *tx_desc = xsk_ring_prod__tx_desc(&xsk->tx, idx + i);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix two warnings reported by compiler by pre-initializing variable.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210313210920.1959628-4-andrii@kernel.org
105b842ba4