linuxdebug/tools/testing/selftests/bpf/prog_tests/exhandler.c

44 lines
1.2 KiB
C
Raw Permalink Normal View History

2024-07-16 15:50:57 +02:00
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021, Oracle and/or its affiliates. */
#include <test_progs.h>
/* Test that verifies exception handling is working. fork()
* triggers task_newtask tracepoint; that new task will have a
* NULL pointer task_works, and the associated task->task_works->func
* should not be NULL if task_works itself is non-NULL.
*
* So to verify exception handling we want to see a NULL task_works
* and task_works->func; if we see this we can conclude that the
* exception handler ran when we attempted to dereference task->task_works
* and zeroed the destination register.
*/
#include "exhandler_kern.skel.h"
void test_exhandler(void)
{
int err = 0, duration = 0, status;
struct exhandler_kern *skel;
pid_t cpid;
skel = exhandler_kern__open_and_load();
if (CHECK(!skel, "skel_load", "skeleton failed: %d\n", err))
goto cleanup;
skel->bss->test_pid = getpid();
err = exhandler_kern__attach(skel);
if (!ASSERT_OK(err, "attach"))
goto cleanup;
cpid = fork();
if (!ASSERT_GT(cpid, -1, "fork failed"))
goto cleanup;
if (cpid == 0)
_exit(0);
waitpid(cpid, &status, 0);
ASSERT_NEQ(skel->bss->exception_triggered, 0, "verify exceptions occurred");
cleanup:
exhandler_kern__destroy(skel);
}