1 files changed, 20 insertions, 14 deletions

diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c
index 87ae476d1c4f..42acc3b52017 100644
--- a/arch/parisc/kernel/unwind.c
+++ b/arch/parisc/kernel/unwind.c
@@ -14,6 +14,7 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/sort.h>
+#include <linux/sched/task_stack.h>
 
 #include <linux/uaccess.h>
 #include <asm/assembly.h>
@@ -21,6 +22,8 @@
 #include <asm/ptrace.h>
 
 #include <asm/unwind.h>
+#include <asm/switch_to.h>
+#include <asm/sections.h>
 
 /* #define DEBUG 1 */
 #ifdef DEBUG
@@ -203,6 +206,11 @@ int __init unwind_init(void)
 	return 0;
 }
 
+static bool pc_is_kernel_fn(unsigned long pc, void *fn)
+{
+	return (unsigned long)dereference_kernel_function_descriptor(fn) == pc;
+}
+
 static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int frame_size)
 {
 	/*
@@ -221,7 +229,7 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int
 	extern void * const _call_on_stack;
 #endif /* CONFIG_IRQSTACKS */
 
-	if (pc == (unsigned long) &handle_interruption) {
+	if (pc_is_kernel_fn(pc, handle_interruption)) {
 		struct pt_regs *regs = (struct pt_regs *)(info->sp - frame_size - PT_SZ_ALGN);
 		dbg("Unwinding through handle_interruption()\n");
 		info->prev_sp = regs->gr[30];
@@ -229,13 +237,13 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int
 		return 1;
 	}
 
-	if (pc == (unsigned long) &ret_from_kernel_thread ||
-	    pc == (unsigned long) &syscall_exit) {
+	if (pc_is_kernel_fn(pc, ret_from_kernel_thread) ||
+	    pc_is_kernel_fn(pc, syscall_exit)) {
 		info->prev_sp = info->prev_ip = 0;
 		return 1;
 	}
 
-	if (pc == (unsigned long) &intr_return) {
+	if (pc_is_kernel_fn(pc, intr_return)) {
 		struct pt_regs *regs;
 
 		dbg("Found intr_return()\n");
@@ -246,20 +254,20 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int
 		return 1;
 	}
 
-	if (pc == (unsigned long) &_switch_to_ret) {
+	if (pc_is_kernel_fn(pc, _switch_to) ||
+	    pc_is_kernel_fn(pc, _switch_to_ret)) {
 		info->prev_sp = info->sp - CALLEE_SAVE_FRAME_SIZE;
 		info->prev_ip = *(unsigned long *)(info->prev_sp - RP_OFFSET);
 		return 1;
 	}
 
 #ifdef CONFIG_IRQSTACKS
-	if (pc == (unsigned long) &_call_on_stack) {
+	if (pc_is_kernel_fn(pc, _call_on_stack)) {
 		info->prev_sp = *(unsigned long *)(info->sp - FRAME_SIZE - REG_SZ);
 		info->prev_ip = *(unsigned long *)(info->sp - FRAME_SIZE - RP_OFFSET);
 		return 1;
 	}
 #endif
-
 	return 0;
 }
 
@@ -292,17 +300,15 @@ 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)) {
+			/* Check if stack is inside kernel stack area */
+			if ((info->prev_sp - (unsigned long) task_stack_page(info->t))
+					>= THREAD_SIZE) {
 				info->prev_sp = 0;
 				break;
 			}
 
-			if (get_user(tmp, (unsigned long *)(info->prev_sp - RP_OFFSET))) 
+			if (copy_from_kernel_nofault(&tmp,
+			    (void *)info->prev_sp - RP_OFFSET, sizeof(tmp)))
 				break;
 			info->prev_ip = tmp;
 			sp = info->prev_sp;