When enable CONFIG_PREEMPT_RT, the kernel will warn when run timer selftests by './test_progs -t timer': BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 In order to avoid such warning, reject bpf_timer in verifier when PREEMPT_RT is enabled. Signed-off-by: Leon Hwang --- kernel/bpf/verifier.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index c89e2b1bc644b..9fb1f957a0937 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -8547,6 +8547,10 @@ static int process_timer_func(struct bpf_verifier_env *env, int regno, verifier_bug(env, "Two map pointers in a timer helper"); return -EFAULT; } + if (IS_ENABLED(CONFIG_PREEMPT_RT)) { + verbose(env, "bpf_timer cannot be used for PREEMPT_RT.\n"); + return -EOPNOTSUPP; + } meta->map_uid = reg->map_uid; meta->map_ptr = map; return 0; -- 2.50.1 When enable CONFIG_PREEMPT_RT, verifier will reject bpf_timer with returning -EOPNOTSUPP. Therefore, skip test cases when errno is EOPNOTSUPP. cd tools/testing/selftests/bpf ./test_progs -t timer 125 free_timer:SKIP 456 timer:SKIP 457/1 timer_crash/array:SKIP 457/2 timer_crash/hash:SKIP 457 timer_crash:SKIP 458 timer_lockup:SKIP 459 timer_mim:SKIP Summary: 5/0 PASSED, 6 SKIPPED, 0 FAILED Signed-off-by: Leon Hwang --- tools/testing/selftests/bpf/prog_tests/free_timer.c | 4 ++++ tools/testing/selftests/bpf/prog_tests/timer.c | 4 ++++ tools/testing/selftests/bpf/prog_tests/timer_crash.c | 4 ++++ tools/testing/selftests/bpf/prog_tests/timer_lockup.c | 4 ++++ tools/testing/selftests/bpf/prog_tests/timer_mim.c | 4 ++++ 5 files changed, 20 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/free_timer.c b/tools/testing/selftests/bpf/prog_tests/free_timer.c index b7b77a6b29799..0de8facca4c5b 100644 --- a/tools/testing/selftests/bpf/prog_tests/free_timer.c +++ b/tools/testing/selftests/bpf/prog_tests/free_timer.c @@ -124,6 +124,10 @@ void test_free_timer(void) int err; skel = free_timer__open_and_load(); + if (!skel && errno == EOPNOTSUPP) { + test__skip(); + return; + } if (!ASSERT_OK_PTR(skel, "open_load")) return; diff --git a/tools/testing/selftests/bpf/prog_tests/timer.c b/tools/testing/selftests/bpf/prog_tests/timer.c index d66687f1ee6a8..56f660ca567ba 100644 --- a/tools/testing/selftests/bpf/prog_tests/timer.c +++ b/tools/testing/selftests/bpf/prog_tests/timer.c @@ -86,6 +86,10 @@ void serial_test_timer(void) int err; timer_skel = timer__open_and_load(); + if (!timer_skel && errno == EOPNOTSUPP) { + test__skip(); + return; + } if (!ASSERT_OK_PTR(timer_skel, "timer_skel_load")) return; diff --git a/tools/testing/selftests/bpf/prog_tests/timer_crash.c b/tools/testing/selftests/bpf/prog_tests/timer_crash.c index f74b82305da8c..b841597c8a3a3 100644 --- a/tools/testing/selftests/bpf/prog_tests/timer_crash.c +++ b/tools/testing/selftests/bpf/prog_tests/timer_crash.c @@ -12,6 +12,10 @@ static void test_timer_crash_mode(int mode) struct timer_crash *skel; skel = timer_crash__open_and_load(); + if (!skel && errno == EOPNOTSUPP) { + test__skip(); + return; + } if (!ASSERT_OK_PTR(skel, "timer_crash__open_and_load")) return; skel->bss->pid = getpid(); diff --git a/tools/testing/selftests/bpf/prog_tests/timer_lockup.c b/tools/testing/selftests/bpf/prog_tests/timer_lockup.c index 1a2f99596916f..eb303fa1e09af 100644 --- a/tools/testing/selftests/bpf/prog_tests/timer_lockup.c +++ b/tools/testing/selftests/bpf/prog_tests/timer_lockup.c @@ -59,6 +59,10 @@ void test_timer_lockup(void) } skel = timer_lockup__open_and_load(); + if (!skel && errno == EOPNOTSUPP) { + test__skip(); + return; + } if (!ASSERT_OK_PTR(skel, "timer_lockup__open_and_load")) return; diff --git a/tools/testing/selftests/bpf/prog_tests/timer_mim.c b/tools/testing/selftests/bpf/prog_tests/timer_mim.c index 9ff7843909e7d..c930c7d7105b9 100644 --- a/tools/testing/selftests/bpf/prog_tests/timer_mim.c +++ b/tools/testing/selftests/bpf/prog_tests/timer_mim.c @@ -65,6 +65,10 @@ void serial_test_timer_mim(void) goto cleanup; timer_skel = timer_mim__open_and_load(); + if (!timer_skel && errno == EOPNOTSUPP) { + test__skip(); + return; + } if (!ASSERT_OK_PTR(timer_skel, "timer_skel_load")) goto cleanup; -- 2.50.1