diff --git a/Documentation/fault-injection/fault-injection.txt b/Documentation/fault-injection/fault-injection.txt
index cf075c20eda0fe5fa75af8d2dd2612a5971638b2..6d6e5ac5ea9272449f6a62c25c35c97d7d54dd5f 100644
--- a/Documentation/fault-injection/fault-injection.txt
+++ b/Documentation/fault-injection/fault-injection.txt
@@ -73,13 +73,17 @@ configuration of fault-injection capabilities.
Any positive value limits failures to only processes indicated by
/proc/<pid>/make-it-fail==1.
-- /debug/*/address-start:
-- /debug/*/address-end:
+- /debug/*/require-start:
+- /debug/*/require-end:
+- /debug/*/reject-start:
+- /debug/*/reject-end:
specifies the range of virtual addresses tested during
stacktrace walking. Failure is injected only if some caller
- in the walked stacktrace lies within this range.
- Default is [0,ULONG_MAX) (whole of virtual address space).
+ in the walked stacktrace lies within the required range, and
+ none lies within the rejected range.
+ Default required range is [0,ULONG_MAX) (whole of virtual address space).
+ Default rejected range is [0,0).
- /debug/*/stacktrace-depth:
diff --git a/include/linux/fault-inject.h b/include/linux/fault-inject.h
index a525f9b9f015798383c81f227402c40249555a6b..9bb584e8939944759e0565016ae213b5c43aad8c 100644
--- a/include/linux/fault-inject.h
+++ b/include/linux/fault-inject.h
@@ -18,6 +18,11 @@ struct fault_attr {
atomic_t space;
unsigned long verbose;
u32 task_filter;
+ unsigned long stacktrace_depth;
+ unsigned long require_start;
+ unsigned long require_end;
+ unsigned long reject_start;
+ unsigned long reject_end;
unsigned long count;
@@ -32,6 +37,11 @@ struct fault_attr {
struct dentry *space_file;
struct dentry *verbose_file;
struct dentry *task_filter_file;
+ struct dentry *stacktrace_depth_file;
+ struct dentry *require_start_file;
+ struct dentry *require_end_file;
+ struct dentry *reject_start_file;
+ struct dentry *reject_end_file;
} dentries;
#endif
@@ -40,6 +50,8 @@ struct fault_attr {
#define FAULT_ATTR_INITIALIZER { \
.interval = 1, \
.times = ATOMIC_INIT(1), \
+ .require_end = ULONG_MAX, \
+ .stacktrace_depth = 32, \
}
#define DECLARE_FAULT_ATTR(name) struct fault_attr name = FAULT_ATTR_INITIALIZER
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 336241bf0ced59520a6dd7c07cd925c87d55e890..1449ca1bf5725e2d56e8d87943c0e811577e1fa8 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -416,6 +416,11 @@ config LKDTM
config FAULT_INJECTION
bool
+ select STACKTRACE
+ select FRAME_POINTER
+ help
+ Provide fault-injection framework.
+ For more details, see Documentation/fault-injection/.
config FAILSLAB
bool "Fault-injection capabilitiy for kmalloc"
diff --git a/lib/fault-inject.c b/lib/fault-inject.c
index 03468609d701c30808b001acfe09dc4039f490c3..361c6e9cd77f371c10b10d933af42897cf7313c9 100644
--- a/lib/fault-inject.c
+++ b/lib/fault-inject.c
@@ -6,6 +6,9 @@
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/interrupt.h>
+#include <linux/unwind.h>
+#include <linux/stacktrace.h>
+#include <linux/kallsyms.h>
#include <linux/fault-inject.h>
/*
@@ -50,6 +53,86 @@ static int fail_task(struct fault_attr *attr, struct task_struct *task)
return !in_interrupt() && task->make_it_fail;
}
+#ifdef CONFIG_STACK_UNWIND
+
+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 0;
+ if (attr->require_start <= UNW_PC(info) &&
+ UNW_PC(info) < attr->require_end)
+ found = 1;
+ }
+ return found;
+}
+
+static int fail_stacktrace(struct fault_attr *attr)
+{
+ struct unwind_frame_info info;
+
+ return unwind_init_running(&info, fail_stacktrace_callback, attr);
+}
+
+#elif defined(CONFIG_STACKTRACE)
+
+#define MAX_STACK_TRACE_DEPTH 32
+
+static int fail_stacktrace(struct fault_attr *attr)
+{
+ struct stack_trace trace;
+ int depth = attr->stacktrace_depth;
+ unsigned long entries[MAX_STACK_TRACE_DEPTH];
+ int n;
+ bool found = (attr->require_start == 0 && attr->require_end == ULONG_MAX);
+
+ if (depth == 0)
+ return found;
+
+ trace.nr_entries = 0;
+ trace.entries = entries;
+ trace.max_entries = (depth < MAX_STACK_TRACE_DEPTH) ?
+ depth : MAX_STACK_TRACE_DEPTH;
+ trace.skip = 1;
+ trace.all_contexts = 0;
+
+ save_stack_trace(&trace, NULL);
+ for (n = 0; n < trace.nr_entries; n++) {
+ if (attr->reject_start <= entries[n] &&
+ entries[n] < attr->reject_end)
+ return 0;
+ if (attr->require_start <= entries[n] &&
+ entries[n] < attr->require_end)
+ found = 1;
+ }
+ return found;
+}
+
+#else
+
+static inline int fail_stacktrace(struct fault_attr *attr)
+{
+ static int firsttime = 1;
+
+ if (firsttime) {
+ printk(KERN_WARNING
+ "This architecture does not implement save_stack_trace()\n");
+ firsttime = 0;
+ }
+ return 0;
+}
+
+#endif
+
/*
* This code is stolen from failmalloc-1.0
* http://www.nongnu.org/failmalloc/
@@ -60,6 +143,9 @@ int should_fail(struct fault_attr *attr, ssize_t size)
if (attr->task_filter && !fail_task(attr, current))
return 0;
+ if (!fail_stacktrace(attr))
+ return 0;
+
if (atomic_read(&attr->times) == 0)
return 0;
@@ -147,6 +233,21 @@ void cleanup_fault_attr_dentries(struct fault_attr *attr)
debugfs_remove(attr->dentries.task_filter_file);
attr->dentries.task_filter_file = NULL;
+ debugfs_remove(attr->dentries.stacktrace_depth_file);
+ attr->dentries.stacktrace_depth_file = NULL;
+
+ debugfs_remove(attr->dentries.require_start_file);
+ attr->dentries.require_start_file = NULL;
+
+ debugfs_remove(attr->dentries.require_end_file);
+ attr->dentries.require_end_file = NULL;
+
+ debugfs_remove(attr->dentries.reject_start_file);
+ attr->dentries.reject_start_file = NULL;
+
+ debugfs_remove(attr->dentries.reject_end_file);
+ attr->dentries.reject_end_file = NULL;
+
if (attr->dentries.dir)
WARN_ON(!simple_empty(attr->dentries.dir));
@@ -184,9 +285,32 @@ int init_fault_attr_dentries(struct fault_attr *attr, const char *name)
attr->dentries.task_filter_file = debugfs_create_bool("task-filter",
mode, dir, &attr->task_filter);
+ attr->dentries.stacktrace_depth_file =
+ debugfs_create_ul("stacktrace-depth", mode, dir,
+ &attr->stacktrace_depth);
+
+ attr->dentries.require_start_file =
+ debugfs_create_ul("require-start", mode, dir, &attr->require_start);
+
+ attr->dentries.require_end_file =
+ debugfs_create_ul("require-end", mode, dir, &attr->require_end);
+
+ attr->dentries.reject_start_file =
+ debugfs_create_ul("reject-start", mode, dir, &attr->reject_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.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
+ )
goto fail;
return 0;