6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yonghong Song <yonghong.song@xxxxxxxxx> [ Upstream commit e7f31873176a345d72ca77c7b4da48493ccd9efd ] 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@xxxxxxxxx> Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx> Tested-by: Eduard Zingerman <eddyz87@xxxxxxxxx> Link: https://lore.kernel.org/bpf/20240205052914.1742687-1-yonghong.song@xxxxxxxxx Stable-dep-of: 16b795cc5952 ("selftests/bpf: Fix redefinition errors compiling lwt_reroute.c") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/testing/selftests/bpf/prog_tests/lwt_helpers.h | 2 -- tools/testing/selftests/bpf/prog_tests/lwt_redirect.c | 1 + tools/testing/selftests/bpf/prog_tests/lwt_reroute.c | 1 + 3 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h b/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h index 61333f2a03f91..68c08309dbc82 100644 --- a/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h +++ b/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h @@ -27,8 +27,6 @@ } \ }) -#define NETNS "ns_lwt" - static inline int netns_create(void) { return system("ip netns add " NETNS); diff --git a/tools/testing/selftests/bpf/prog_tests/lwt_redirect.c b/tools/testing/selftests/bpf/prog_tests/lwt_redirect.c index ea326e26656f5..7b458ae5f0f85 100644 --- a/tools/testing/selftests/bpf/prog_tests/lwt_redirect.c +++ b/tools/testing/selftests/bpf/prog_tests/lwt_redirect.c @@ -53,6 +53,7 @@ #include <stdbool.h> #include <stdlib.h> +#define NETNS "ns_lwt_redirect" #include "lwt_helpers.h" #include "test_progs.h" #include "network_helpers.h" diff --git a/tools/testing/selftests/bpf/prog_tests/lwt_reroute.c b/tools/testing/selftests/bpf/prog_tests/lwt_reroute.c index f4bb2d5fcae0a..c104f07f1b0bc 100644 --- a/tools/testing/selftests/bpf/prog_tests/lwt_reroute.c +++ b/tools/testing/selftests/bpf/prog_tests/lwt_reroute.c @@ -48,6 +48,7 @@ * For case 2, force UDP packets to overflow fq limit. As long as kernel * is not crashed, it is considered successful. */ +#define NETNS "ns_lwt_reroute" #include "lwt_helpers.h" #include "network_helpers.h" #include <linux/net_tstamp.h> -- 2.43.0