1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2021, Oracle and/or its affiliates. */
3
4 #include <test_progs.h>
5
6 /* Test that verifies exception handling is working. fork()
7 * triggers task_newtask tracepoint; that new task will have a
8 * NULL pointer task_works, and the associated task->task_works->func
9 * should not be NULL if task_works itself is non-NULL.
10 *
11 * So to verify exception handling we want to see a NULL task_works
12 * and task_works->func; if we see this we can conclude that the
13 * exception handler ran when we attempted to dereference task->task_works
14 * and zeroed the destination register.
15 */
16 #include "exhandler_kern.skel.h"
17
18 void test_exhandler(void)
19 {
20 int err = 0, duration = 0, status;
21 struct exhandler_kern *skel;
22 pid_t cpid;
23
24 skel = exhandler_kern__open_and_load();
25 if (CHECK(!skel, "skel_load", "skeleton failed: %d\n", err))
26 goto cleanup;
27
28 skel->bss->test_pid = getpid();
29
30 err = exhandler_kern__attach(skel);
31 if (!ASSERT_OK(err, "attach"))
32 goto cleanup;
33 cpid = fork();
34 if (!ASSERT_GT(cpid, -1, "fork failed"))
35 goto cleanup;
36 if (cpid == 0)
37 _exit(0);
38 waitpid(cpid, &status, 0);
39
40 ASSERT_NEQ(skel->bss->exception_triggered, 0, "verify exceptions occurred");
41 cleanup:
42 exhandler_kern__destroy(skel);
43 }
44
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