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-rw-r--r--arch/powerpc/kernel/ftrace.c2
-rw-r--r--arch/s390/kernel/ftrace.c2
-rw-r--r--arch/x86/Kconfig1
-rw-r--r--arch/x86/kernel/entry_32.S2
-rw-r--r--arch/x86/kernel/entry_64.S2
-rw-r--r--arch/x86/kernel/ftrace.c6
-rw-r--r--include/linux/ftrace.h4
-rw-r--r--kernel/trace/Kconfig7
-rw-r--r--kernel/trace/trace_functions_graph.c36
9 files changed, 53 insertions, 9 deletions
diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index 2d182f1..58d6a61 100644
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -605,7 +605,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
return;
}
- if (ftrace_push_return_trace(old, self_addr, &trace.depth) == -EBUSY) {
+ if (ftrace_push_return_trace(old, self_addr, &trace.depth, 0) == -EBUSY) {
*parent = old;
return;
}
diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 82ddfd3..3e298e6 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -190,7 +190,7 @@ unsigned long prepare_ftrace_return(unsigned long ip, unsigned long parent)
goto out;
if (unlikely(atomic_read(&current->tracing_graph_pause)))
goto out;
- if (ftrace_push_return_trace(parent, ip, &trace.depth) == -EBUSY)
+ if (ftrace_push_return_trace(parent, ip, &trace.depth, 0) == -EBUSY)
goto out;
trace.func = ftrace_mcount_call_adjust(ip) & PSW_ADDR_INSN;
/* Only trace if the calling function expects to. */
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 356d2ec..fcf12af 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -33,6 +33,7 @@ config X86
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_TRACER
select HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_FUNCTION_GRAPH_FP_TEST
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
select HAVE_FTRACE_SYSCALLS
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index c929add..0d4b285 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -1154,6 +1154,7 @@ ENTRY(ftrace_graph_caller)
pushl %edx
movl 0xc(%esp), %edx
lea 0x4(%ebp), %eax
+ movl (%ebp), %ecx
subl $MCOUNT_INSN_SIZE, %edx
call prepare_ftrace_return
popl %edx
@@ -1168,6 +1169,7 @@ return_to_handler:
pushl %eax
pushl %ecx
pushl %edx
+ movl %ebp, %eax
call ftrace_return_to_handler
movl %eax, 0xc(%esp)
popl %edx
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index de74f0a..c251be7 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -135,6 +135,7 @@ ENTRY(ftrace_graph_caller)
leaq 8(%rbp), %rdi
movq 0x38(%rsp), %rsi
+ movq (%rbp), %rdx
subq $MCOUNT_INSN_SIZE, %rsi
call prepare_ftrace_return
@@ -150,6 +151,7 @@ GLOBAL(return_to_handler)
/* Save the return values */
movq %rax, (%rsp)
movq %rdx, 8(%rsp)
+ movq %rbp, %rdi
call ftrace_return_to_handler
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index b79c553..d94e1ea 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -408,7 +408,8 @@ int ftrace_disable_ftrace_graph_caller(void)
* Hook the return address and push it in the stack of return addrs
* in current thread info.
*/
-void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
+void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
+ unsigned long frame_pointer)
{
unsigned long old;
int faulted;
@@ -453,7 +454,8 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
return;
}
- if (ftrace_push_return_trace(old, self_addr, &trace.depth) == -EBUSY) {
+ if (ftrace_push_return_trace(old, self_addr, &trace.depth,
+ frame_pointer) == -EBUSY) {
*parent = old;
return;
}
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 39b95c5..dc3b132 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -362,6 +362,7 @@ struct ftrace_ret_stack {
unsigned long func;
unsigned long long calltime;
unsigned long long subtime;
+ unsigned long fp;
};
/*
@@ -372,7 +373,8 @@ struct ftrace_ret_stack {
extern void return_to_handler(void);
extern int
-ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth);
+ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
+ unsigned long frame_pointer);
/*
* Sometimes we don't want to trace a function with the function
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 1eac852..b17ed87 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -18,6 +18,13 @@ config HAVE_FUNCTION_TRACER
config HAVE_FUNCTION_GRAPH_TRACER
bool
+config HAVE_FUNCTION_GRAPH_FP_TEST
+ bool
+ help
+ An arch may pass in a unique value (frame pointer) to both the
+ entering and exiting of a function. On exit, the value is compared
+ and if it does not match, then it will panic the kernel.
+
config HAVE_FUNCTION_TRACE_MCOUNT_TEST
bool
help
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 8b59241..d2249ab 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 = {
/* Add a function return address to the trace stack on thread info.*/
int
-ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
+ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
+ unsigned long frame_pointer)
{
unsigned long long calltime;
int index;
@@ -85,6 +86,7 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
current->ret_stack[index].func = func;
current->ret_stack[index].calltime = calltime;
current->ret_stack[index].subtime = 0;
+ current->ret_stack[index].fp = frame_pointer;
*depth = index;
return 0;
@@ -92,7 +94,8 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth)
/* Retrieve a function return address to the trace stack on thread info.*/
static void
-ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
+ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
+ unsigned long frame_pointer)
{
int index;
@@ -106,6 +109,31 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
return;
}
+#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
+ /*
+ * The arch may choose to record the frame pointer used
+ * and check it here to make sure that it is what we expect it
+ * to be. If gcc does not set the place holder of the return
+ * address in the frame pointer, and does a copy instead, then
+ * the function graph trace will fail. This test detects this
+ * case.
+ *
+ * Currently, x86_32 with optimize for size (-Os) makes the latest
+ * gcc do the above.
+ */
+ if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
+ ftrace_graph_stop();
+ WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
+ " from func %pF return to %lx\n",
+ current->ret_stack[index].fp,
+ frame_pointer,
+ (void *)current->ret_stack[index].func,
+ current->ret_stack[index].ret);
+ *ret = (unsigned long)panic;
+ return;
+ }
+#endif
+
*ret = current->ret_stack[index].ret;
trace->func = current->ret_stack[index].func;
trace->calltime = current->ret_stack[index].calltime;
@@ -117,12 +145,12 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret)
* Send the trace to the ring-buffer.
* @return the original return address.
*/
-unsigned long ftrace_return_to_handler(void)
+unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
{
struct ftrace_graph_ret trace;
unsigned long ret;
- ftrace_pop_return_trace(&trace, &ret);
+ ftrace_pop_return_trace(&trace, &ret, frame_pointer);
trace.rettime = trace_clock_local();
ftrace_graph_return(&trace);
barrier();