Commit e77900ab authored by Helge Deller's avatar Helge Deller
Browse files

parisc: Stop unwinding at start of stack 



Check stack pointer if we are reaching the stack end and stop unwinding
if we do. This fixes early backtraces and avoids showing unrealistic
call stacks.

Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 432654df

arch/parisc/kernel/unwind.c

+12 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
#include <linux/slab.h>

#include <linux/kallsyms.h>

#include <linux/sort.h>

#include <linux/sched.h>



#include <linux/uaccess.h>

#include <asm/assembly.h>
@@ -279,6 +280,17 @@ static void unwind_frame_regs(struct unwind_frame_info *info) 


			info->prev_sp = sp - 64;

			info->prev_ip = 0;



			/* The stack is at the end inside the thread_union

			 * struct. If we reach data, we have reached the

			 * beginning of the stack and should stop unwinding. */

			if (info->prev_sp >= (unsigned long) task_thread_info(info->t) &&

			    info->prev_sp < ((unsigned long) task_thread_info(info->t)

						+ THREAD_SZ_ALGN)) {

				info->prev_sp = 0;

				break;

			}



			if (get_user(tmp, (unsigned long *)(info->prev_sp - RP_OFFSET))) 

				break;

			info->prev_ip = tmp;