3 Commits

Author	SHA1	Message	Date
Yonghong Song	e7f3187317	selftests/bpf: Fix flaky selftest lwt_redirect/lwt_reroute ... Recently, when running './test_progs -j', I occasionally hit the following errors: test_lwt_redirect:PASS:pthread_create 0 nsec test_lwt_redirect_run:FAIL:netns_create unexpected error: 256 (errno 0) #142/2 lwt_redirect/lwt_redirect_normal_nomac:FAIL #142 lwt_redirect:FAIL test_lwt_reroute:PASS:pthread_create 0 nsec test_lwt_reroute_run:FAIL:netns_create unexpected error: 256 (errno 0) test_lwt_reroute:PASS:pthread_join 0 nsec #143/2 lwt_reroute/lwt_reroute_qdisc_dropped:FAIL #143 lwt_reroute:FAIL The netns_create() definition looks like below: #define NETNS "ns_lwt" static inline int netns_create(void) { return system("ip netns add " NETNS); } One possibility is that both lwt_redirect and lwt_reroute create netns with the same name "ns_lwt" which may cause conflict. I tried the following example: $ sudo ip netns add abc $ echo $? 0 $ sudo ip netns add abc Cannot create namespace file "/var/run/netns/abc": File exists $ echo $? 1 $ The return code for above netns_create() is 256. The internet search suggests that the return value for 'ip netns add ns_lwt' is 1, which matches the above 'sudo ip netns add abc' example. This patch tried to use different netns names for two tests to avoid 'ip netns add <name>' failure. I ran './test_progs -j' 10 times and all succeeded with lwt_redirect/lwt_reroute tests. Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240205052914.1742687-1-yonghong.song@linux.dev	2024-02-05 11:13:36 -08:00
Martin KaFai Lau	fbaf59a9f5	selftests/bpf: Remove "&>" usage in the selftests ... In s390, CI reported that the sock_iter_batch selftest hits this error very often: 2024-01-26T16:56:49.3091804Z Bind /proc/self/ns/net -> /run/netns/sock_iter_batch_netns failed: No such file or directory 2024-01-26T16:56:49.3149524Z Cannot remove namespace file "/run/netns/sock_iter_batch_netns": No such file or directory 2024-01-26T16:56:49.3772213Z test_sock_iter_batch:FAIL:ip netns add sock_iter_batch_netns unexpected error: 256 (errno 0) It happens very often in s390 but Manu also noticed it happens very sparsely in other arch also. It turns out the default dash shell does not recognize "&>" as a redirection operator, so the command went to the background. In the sock_iter_batch selftest, the "ip netns delete" went into background and then race with the following "ip netns add" command. This patch replaces the "&> /dev/null" usage with ">/dev/null 2>&1" and does this redirection in the SYS_NOFAIL macro instead of doing it individually by its caller. The SYS_NOFAIL callers do not care about failure, so it is no harm to do this redirection even if some of the existing callers do not redirect to /dev/null now. It touches different test files, so I skipped the Fixes tags in this patch. Some of the changed tests do not use "&>" but they use the SYS_NOFAIL, so these tests are also changed to avoid doing its own redirection because SYS_NOFAIL does it internally now. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240127025017.950825-1-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>	2024-01-29 12:48:32 -08:00
Yan Zhai	6c77997bc6	selftests/bpf: Add lwt_xmit tests for BPF_REROUTE ... There is no lwt test case for BPF_REROUTE yet. Add test cases for both normal and abnormal situations. The abnormal situation is set up with an fq qdisc on the reroute target device. Without proper fixes, overflow this qdisc queue limit (to trigger a drop) would panic the kernel. Signed-off-by: Yan Zhai <yan@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/62c8ddc1e924269dcf80d2e8af1a1e632cee0b3a.1692326837.git.yan@cloudflare.com	2023-08-18 16:05:27 +02:00