tests: filter-out spurious references to bpf module symbols from kall…

…modsyms

We see references to symbols assigned to a "bpf" module in
/proc/kallmodsyms.  We filter these references out in a few tests and in
libdtrace/dt_module.c.

The tests which were failing before the changes here include:
test/unittest/aggs/tst.aggmod_full.sh
test/unittest/aggs/tst.aggmod_full2.sh
test/unittest/consumer/tst.merge_ranges_bug25767469.c
test/unittest/consumer/tst.symbols.c

Signed-off-by: Eugene Loh <eugene.loh@oracle.com>
Signed-off-by: David Mc Lean <david.mclean@oracle.com>
Reviewed-by: Kris Van Hees <kris.van.hees@oracle.com>

libdtrace/dt_module.c

@@ -1,6 +1,6 @@
 /*
  * Oracle Linux DTrace.
- * Copyright (c) 2009, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2009, 2020, Oracle and/or its affiliates. All rights reserved.
  * Licensed under the Universal Permissive License v 1.0 as shown at
  * http://oss.oracle.com/licenses/upl.
  */
@@ -1122,6 +1122,9 @@ dt_modsym_update(dtrace_hdl_t *dtp, const char *line)
 	     || (sym_type == 'w') || (sym_type == 'W');
 	mod_name[strlen(mod_name)-1] = '\0';	/* chop trailing ] */
 
+	if (strcmp(mod_name, "bpf") == 0)
+		return 0;
+
 	/*
 	 * Symbols of "absolute" type are typically defined per CPU.  Their
 	 * "addresses" in /proc/kallmodsyms are very low and are actually offsets.

test/unittest/aggs/tst.aggmod_full.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 # Oracle Linux DTrace.
-# Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2017, 2020, Oracle and/or its affiliates. All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # http://oss.oracle.com/licenses/upl.
 #
@@ -84,6 +84,7 @@ NF == 4 && $4 == "__init_scratch_begin" {
 NF == 4 {$5 = "[vmlinux]"};
 $3 == "a" {$2 = 0};
 $3 == "A" {$2 = 0};
+$5 == "[bpf]" {$2 = 0};
 $2 != 0 { print $1 >> $5 }
 ' /proc/kallmodsyms
 

test/unittest/aggs/tst.aggmod_full2.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 # Oracle Linux DTrace.
-# Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # http://oss.oracle.com/licenses/upl.
 #
@@ -41,6 +41,7 @@ cat > test.c << EOF
 #include <string.h>
 #include <unistd.h>
 #include <linux/limits.h>
+#include <time.h>
 #include "prov.h"
 
 /*
@@ -90,6 +91,9 @@ int main(int argc, char **argv) {
 		if (size == 0)
 			continue;
 
+		if (strcmp(modname, "bpf]") == 0)
+			continue;
+
 		/* trim the trailing ']' and print modname to stdout */
 		modname[strlen(modname)-1] = '\0';
 		printf("%s\n", modname);

test/unittest/consumer/tst.symbols.c

@@ -1,6 +1,6 @@
 /*
  * Oracle Linux DTrace.
- * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
  * Licensed under the Universal Permissive License v 1.0 as shown at
  * http://oss.oracle.com/licenses/upl.
  */
@@ -107,6 +107,8 @@ int read_symbols() {
 			continue;
 		}
 #undef KERNEL_FLAG_INIT_SCRATCH
+		if (strcmp(modname, "bpf]") == 0)
+			continue;
 
 		/*
 		 * In libdtrace/dt_module.c function dt_modsym_update(),