Merge branch 'fix-verifier-test-failures-in-verbose-mode'

Gregory Bell says:

====================
Fix verifier test failures in verbose mode

This patch series fixes two issues that cause false failures in the
BPF verifier test suite when run with verbose output (`-v`).

The following tests fail only when running the test_verifier in
verbose.

This leads to inconsistent results across verbose and
non-verbose runs.

Patch 1 addresses an issue where the verbose flag (`-v`) unintentionally
overrides the `opts.log_level`, leading to incorrect contents when checking
bpf_vlog in tests with `expected_ret == VERBOSE_ACCEPT`. This occurs when
running verbose with `-v` but not `-vv`

Patch 2 increases the size of the `bpf_vlog[]` buffer to prevent truncation
of large verifier logs, which was causing failures in several scale and
64-bit immediate tests.

Before patches:
./test_verifier | grep FAIL
Summary: 790 PASSED, 0 SKIPPED, 0 FAILED

./test_verifier -v | grep FAIL
Summary: 782 PASSED, 0 SKIPPED, 8 FAILED

./test_verifier -vv | grep FAIL
Summary: 787 PASSED, 0 SKIPPED, 3 FAILED

After patches:
./test_verifier -v | grep FAIL
Summary: 790 PASSED, 0 SKIPPED, 0 FAILED
./test_verifier -vv | grep FAIL
Summary: 790 PASSED, 0 SKIPPED, 0 FAILED

These fixes improve test reliability and ensure consistent behavior across
verbose and non-verbose runs.
====================

Tested-by: Eduard Zingerman <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

Author: Alexei Starovoitov

tools/testing/selftests/bpf/test_verifier.c

@@ -734,7 +734,7 @@ static __u32 btf_raw_types[] = {
 	BTF_MEMBER_ENC(71, 13, 128), /* struct prog_test_member __kptr *ptr; */
 };
 
-static char bpf_vlog[UINT_MAX >> 8];
+static char bpf_vlog[UINT_MAX >> 5];
 
 static int load_btf_spec(__u32 *types, int types_len,
 			 const char *strings, int strings_len)
@@ -1559,10 +1559,10 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
 		       test->errstr_unpriv : test->errstr;
 
 	opts.expected_attach_type = test->expected_attach_type;
-	if (verbose)
-		opts.log_level = verif_log_level | 4; /* force stats */
-	else if (expected_ret == VERBOSE_ACCEPT)
+	if (expected_ret == VERBOSE_ACCEPT)
 		opts.log_level = 2;
+	else if (verbose)
+		opts.log_level = verif_log_level | 4; /* force stats */
 	else
 		opts.log_level = DEFAULT_LIBBPF_LOG_LEVEL;
 	opts.prog_flags = pflags;