diff options
Diffstat (limited to 'kernel/trace')
-rw-r--r-- | kernel/trace/Kconfig | 7 | ||||
-rw-r--r-- | kernel/trace/trace_functions_graph.c | 36 |
2 files changed, 39 insertions, 4 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 1eac85253ce9..b17ed8787ded 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig | |||
@@ -18,6 +18,13 @@ config HAVE_FUNCTION_TRACER | |||
18 | config HAVE_FUNCTION_GRAPH_TRACER | 18 | config HAVE_FUNCTION_GRAPH_TRACER |
19 | bool | 19 | bool |
20 | 20 | ||
21 | config HAVE_FUNCTION_GRAPH_FP_TEST | ||
22 | bool | ||
23 | help | ||
24 | An arch may pass in a unique value (frame pointer) to both the | ||
25 | entering and exiting of a function. On exit, the value is compared | ||
26 | and if it does not match, then it will panic the kernel. | ||
27 | |||
21 | config HAVE_FUNCTION_TRACE_MCOUNT_TEST | 28 | config HAVE_FUNCTION_TRACE_MCOUNT_TEST |
22 | bool | 29 | bool |
23 | help | 30 | help |
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 8b592418d8b2..d2249abafb53 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c | |||
@@ -57,7 +57,8 @@ static struct tracer_flags tracer_flags = { | |||
57 | 57 | ||
58 | /* Add a function return address to the trace stack on thread info.*/ | 58 | /* Add a function return address to the trace stack on thread info.*/ |
59 | int | 59 | int |
60 | ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth) | 60 | ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, |
61 | unsigned long frame_pointer) | ||
61 | { | 62 | { |
62 | unsigned long long calltime; | 63 | unsigned long long calltime; |
63 | int index; | 64 | int index; |
@@ -85,6 +86,7 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth) | |||
85 | current->ret_stack[index].func = func; | 86 | current->ret_stack[index].func = func; |
86 | current->ret_stack[index].calltime = calltime; | 87 | current->ret_stack[index].calltime = calltime; |
87 | current->ret_stack[index].subtime = 0; | 88 | current->ret_stack[index].subtime = 0; |
89 | current->ret_stack[index].fp = frame_pointer; | ||
88 | *depth = index; | 90 | *depth = index; |
89 | 91 | ||
90 | return 0; | 92 | return 0; |
@@ -92,7 +94,8 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth) | |||
92 | 94 | ||
93 | /* Retrieve a function return address to the trace stack on thread info.*/ | 95 | /* Retrieve a function return address to the trace stack on thread info.*/ |
94 | static void | 96 | static void |
95 | ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret) | 97 | ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret, |
98 | unsigned long frame_pointer) | ||
96 | { | 99 | { |
97 | int index; | 100 | int index; |
98 | 101 | ||
@@ -106,6 +109,31 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret) | |||
106 | return; | 109 | return; |
107 | } | 110 | } |
108 | 111 | ||
112 | #ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST | ||
113 | /* | ||
114 | * The arch may choose to record the frame pointer used | ||
115 | * and check it here to make sure that it is what we expect it | ||
116 | * to be. If gcc does not set the place holder of the return | ||
117 | * address in the frame pointer, and does a copy instead, then | ||
118 | * the function graph trace will fail. This test detects this | ||
119 | * case. | ||
120 | * | ||
121 | * Currently, x86_32 with optimize for size (-Os) makes the latest | ||
122 | * gcc do the above. | ||
123 | */ | ||
124 | if (unlikely(current->ret_stack[index].fp != frame_pointer)) { | ||
125 | ftrace_graph_stop(); | ||
126 | WARN(1, "Bad frame pointer: expected %lx, received %lx\n" | ||
127 | " from func %pF return to %lx\n", | ||
128 | current->ret_stack[index].fp, | ||
129 | frame_pointer, | ||
130 | (void *)current->ret_stack[index].func, | ||
131 | current->ret_stack[index].ret); | ||
132 | *ret = (unsigned long)panic; | ||
133 | return; | ||
134 | } | ||
135 | #endif | ||
136 | |||
109 | *ret = current->ret_stack[index].ret; | 137 | *ret = current->ret_stack[index].ret; |
110 | trace->func = current->ret_stack[index].func; | 138 | trace->func = current->ret_stack[index].func; |
111 | trace->calltime = current->ret_stack[index].calltime; | 139 | trace->calltime = current->ret_stack[index].calltime; |
@@ -117,12 +145,12 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret) | |||
117 | * Send the trace to the ring-buffer. | 145 | * Send the trace to the ring-buffer. |
118 | * @return the original return address. | 146 | * @return the original return address. |
119 | */ | 147 | */ |
120 | unsigned long ftrace_return_to_handler(void) | 148 | unsigned long ftrace_return_to_handler(unsigned long frame_pointer) |
121 | { | 149 | { |
122 | struct ftrace_graph_ret trace; | 150 | struct ftrace_graph_ret trace; |
123 | unsigned long ret; | 151 | unsigned long ret; |
124 | 152 | ||
125 | ftrace_pop_return_trace(&trace, &ret); | 153 | ftrace_pop_return_trace(&trace, &ret, frame_pointer); |
126 | trace.rettime = trace_clock_local(); | 154 | trace.rettime = trace_clock_local(); |
127 | ftrace_graph_return(&trace); | 155 | ftrace_graph_return(&trace); |
128 | barrier(); | 156 | barrier(); |