x86: Stop recursive fault in print_context_stack after stack overflow

[firefly-linux-kernel-4.4.55.git] / arch / x86 / kernel / dumpstack.c

diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 4025fe4f928f6f4cb2ddcfc0233197e9e0b3ad44..90bf130f09bc16742294154b14f30310d6a11fcd 100644 (file)
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -37,13 +37,16 @@ print_ftrace_graph_addr(unsigned long addr, void *data,
                        const struct stacktrace_ops *ops,
                        struct thread_info *tinfo, int *graph)
 {
-       struct task_struct *task = tinfo->task;
+       struct task_struct *task;
        unsigned long ret_addr;
-       int index = task->curr_ret_stack;
+       int index;
 
        if (addr != (unsigned long)return_to_handler)
                return;
 
+       task = tinfo->task;
+       index = task->curr_ret_stack;
+
        if (!task->ret_stack || index < *graph)
                return;