On 1/8/24 11:05 AM, Jiri Olsa wrote:
On Thu, Jan 04, 2024 at 09:08:17PM +0800, Tiezhu Yang wrote:If CONFIG_BPF_JIT_ALWAYS_ON is not set and bpf_jit_enable is 0, there exist 6 failed tests. [root@linux bpf]# echo 0 > /proc/sys/net/core/bpf_jit_enable [root@linux bpf]# echo 0 > /proc/sys/kernel/unprivileged_bpf_disabled [root@linux bpf]# ./test_verifier | grep FAIL #106/p inline simple bpf_loop call FAIL #107/p don't inline bpf_loop call, flags non-zero FAIL #108/p don't inline bpf_loop call, callback non-constant FAIL #109/p bpf_loop_inline and a dead func FAIL #110/p bpf_loop_inline stack locations for loop vars FAIL #111/p inline bpf_loop call in a big program FAIL Summary: 768 PASSED, 15 SKIPPED, 6 FAILED The test log shows that callbacks are not allowed in non-JITed programs, interpreter doesn't support them yet, thus these tests should be skipped if jit is disabled, just return -ENOTSUPP instead of -EINVAL for pseudo calls in fixup_call_args(). With this patch: [root@linux bpf]# echo 0 > /proc/sys/net/core/bpf_jit_enable [root@linux bpf]# echo 0 > /proc/sys/kernel/unprivileged_bpf_disabled [root@linux bpf]# ./test_verifier | grep FAIL Summary: 768 PASSED, 21 SKIPPED, 0 FAILED Additionally, as Eduard suggested, return -ENOTSUPP instead of -EINVAL for the other three places where "non-JITed" is used in error messages to keep consistent. Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> --- v2: -- rebase on the latest bpf-next tree. -- return -ENOTSUPP instead of -EINVAL for the other three places where "non-JITed" is used in error messages to keep consistent. -- update the patch subject and commit message. kernel/bpf/verifier.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index d5f4ff1eb235..99558a5186b2 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -8908,7 +8908,7 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, goto error; if (env->subprog_cnt > 1 && !allow_tail_call_in_subprogs(env)) { verbose(env, "tail_calls are not allowed in non-JITed programs with bpf-to-bpf calls\n"); - return -EINVAL; + return -ENOTSUPP;FWIW I agree with John review earlier [1], also there's chance (however small) we could mess up with some app already checking on that
+1, the ship on this has sailed unfortunately. Tiezhu, it would be good if you could update the selftest handling instead.
jirka [1] https://lore.kernel.org/bpf/6594a4c15a677_11e86208cd@john.notmuch/
