return !in_interrupt() && task->make_it_fail;
}
-#ifdef CONFIG_STACK_UNWIND
+#define MAX_STACK_TRACE_DEPTH 32
-static asmlinkage int fail_stacktrace_callback(struct unwind_frame_info *info,
- void *arg)
-{
- int depth;
- struct fault_attr *attr = arg;
- bool found = (attr->require_start == 0 && attr->require_end == ULONG_MAX);
-
- for (depth = 0; depth < attr->stacktrace_depth
- && unwind(info) == 0 && UNW_PC(info); depth++) {
- if (arch_unw_user_mode(info))
- break;
- if (attr->reject_start <= UNW_PC(info) &&
- UNW_PC(info) < attr->reject_end)
- return false;
- if (attr->require_start <= UNW_PC(info) &&
- UNW_PC(info) < attr->require_end)
- found = true;
- }
- return found;
-}
-
-static bool fail_stacktrace(struct fault_attr *attr)
-{
- struct unwind_frame_info info;
-
- return unwind_init_running(&info, fail_stacktrace_callback, attr);
-}
-
-#elif defined(CONFIG_STACKTRACE)
+#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
static bool fail_stacktrace(struct fault_attr *attr)
{
trace.nr_entries = 0;
trace.entries = entries;
- trace.max_entries = (depth < MAX_STACK_TRACE_DEPTH) ?
- depth : MAX_STACK_TRACE_DEPTH;
+ trace.max_entries = depth;
trace.skip = 1;
trace.all_contexts = 0;
static inline bool fail_stacktrace(struct fault_attr *attr)
{
- static bool firsttime = true;
-
- if (firsttime) {
- printk(KERN_WARNING
- "This architecture does not implement save_stack_trace()\n");
- firsttime = false;
- }
- return false;
+ return true;
}
-#endif
+#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
/*
* This code is stolen from failmalloc-1.0
if (attr->task_filter && !fail_task(attr, current))
return false;
- if (!fail_stacktrace(attr))
- return false;
-
if (atomic_read(&attr->times) == 0)
return false;
return false;
}
- if (attr->probability > random32() % 100)
- goto fail;
+ if (attr->probability <= random32() % 100)
+ return false;
- return false;
+ if (!fail_stacktrace(attr))
+ return false;
-fail:
fail_dump(attr);
if (atomic_read(&attr->times) != -1)
*(unsigned long *)data = val;
}
+static void debugfs_ul_set_MAX_STACK_TRACE_DEPTH(void *data, u64 val)
+{
+ *(unsigned long *)data =
+ val < MAX_STACK_TRACE_DEPTH ?
+ val : MAX_STACK_TRACE_DEPTH;
+}
+
static u64 debugfs_ul_get(void *data)
{
return *(unsigned long *)data;
return debugfs_create_file(name, mode, parent, value, &fops_ul);
}
+DEFINE_SIMPLE_ATTRIBUTE(fops_ul_MAX_STACK_TRACE_DEPTH, debugfs_ul_get,
+ debugfs_ul_set_MAX_STACK_TRACE_DEPTH, "%llu\n");
+
+static struct dentry *debugfs_create_ul_MAX_STACK_TRACE_DEPTH(
+ const char *name, mode_t mode,
+ struct dentry *parent, unsigned long *value)
+{
+ return debugfs_create_file(name, mode, parent, value,
+ &fops_ul_MAX_STACK_TRACE_DEPTH);
+}
+
static void debugfs_atomic_t_set(void *data, u64 val)
{
atomic_set((atomic_t *)data, val);
debugfs_remove(attr->dentries.task_filter_file);
attr->dentries.task_filter_file = NULL;
+#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
+
debugfs_remove(attr->dentries.stacktrace_depth_file);
attr->dentries.stacktrace_depth_file = NULL;
debugfs_remove(attr->dentries.reject_end_file);
attr->dentries.reject_end_file = NULL;
+#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
+
if (attr->dentries.dir)
WARN_ON(!simple_empty(attr->dentries.dir));
attr->dentries.task_filter_file = debugfs_create_bool("task-filter",
mode, dir, &attr->task_filter);
+ if (!attr->dentries.probability_file || !attr->dentries.interval_file ||
+ !attr->dentries.times_file || !attr->dentries.space_file ||
+ !attr->dentries.verbose_file || !attr->dentries.task_filter_file)
+ goto fail;
+
+#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER
+
attr->dentries.stacktrace_depth_file =
- debugfs_create_ul("stacktrace-depth", mode, dir,
- &attr->stacktrace_depth);
+ debugfs_create_ul_MAX_STACK_TRACE_DEPTH(
+ "stacktrace-depth", mode, dir, &attr->stacktrace_depth);
attr->dentries.require_start_file =
debugfs_create_ul("require-start", mode, dir, &attr->require_start);
attr->dentries.reject_end_file =
debugfs_create_ul("reject-end", mode, dir, &attr->reject_end);
-
- if (!attr->dentries.probability_file || !attr->dentries.interval_file
- || !attr->dentries.times_file || !attr->dentries.space_file
- || !attr->dentries.verbose_file || !attr->dentries.task_filter_file
- || !attr->dentries.stacktrace_depth_file
- || !attr->dentries.require_start_file
- || !attr->dentries.require_end_file
- || !attr->dentries.reject_start_file
- || !attr->dentries.reject_end_file
- )
+ if (!attr->dentries.stacktrace_depth_file ||
+ !attr->dentries.require_start_file ||
+ !attr->dentries.require_end_file ||
+ !attr->dentries.reject_start_file ||
+ !attr->dentries.reject_end_file)
goto fail;
+#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */
+
return 0;
fail:
cleanup_fault_attr_dentries(attr);