sh: ftrace: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack

The structure of the ret_stack array on the task struct is going to
change, and accessing it directly via the curr_ret_stack index will no
longer give the ret_stack entry that holds the return address. To access
that, architectures must now use ftrace_graph_get_ret_stack() to get the
associated ret_stack that matches the saved return address.

Cc: linux-sh@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (VMware) 2018-12-07 13:06:04 -05:00
parent 945626db09
commit cec8d0e7f0
2 changed files with 12 additions and 8 deletions

View File

@ -59,17 +59,20 @@ print_ftrace_graph_addr(unsigned long addr, void *data,
struct thread_info *tinfo, int *graph)
{
struct task_struct *task = tinfo->task;
struct ftrace_ret_stack *ret_stack;
unsigned long ret_addr;
int index = task->curr_ret_stack;
if (addr != (unsigned long)return_to_handler)
return;
if (!task->ret_stack || index < *graph)
if (!task->ret_stack)
return;
index -= *graph;
ret_addr = task->ret_stack[index].ret;
ret_stack = ftrace_graph_get_ret_stack(task, *graph);
if (!ret_stack)
return;
ret_addr = ret_stack->ret;
ops->address(data, ret_addr, 1);

View File

@ -608,17 +608,18 @@ struct dwarf_frame *dwarf_unwind_stack(unsigned long pc,
* expected to find the real return address.
*/
if (pc == (unsigned long)&return_to_handler) {
int index = current->curr_ret_stack;
struct ftrace_ret_stack *ret_stack;
ret_stack = ftrace_graph_get_ret_stack(current, 0);
if (ret_stack)
pc = ret_stack->ret;
/*
* We currently have no way of tracking how many
* return_to_handler()'s we've seen. If there is more
* than one patched return address on our stack,
* complain loudly.
*/
WARN_ON(index > 0);
pc = current->ret_stack[index].ret;
WARN_ON(ftrace_graph_get_ret_stack(current, 1);
}
#endif