Changeset 23628

Timestamp:

01/19/08 05:56:40 (10 months ago)

Author:

bonefish

Message:

An outermost stack frame (having a NULL previous frame) was
incorrectly recognized as iframe. Fixes the read fault when doing "sc"
for a kernel thread.

Location:

haiku/trunk/src/system/kernel/arch/x86

Files:

• arch_debug.cpp (modified) (2 diffs)
• arch_thread.c (modified) (1 diff)

haiku/trunk/src/system/kernel/arch/x86/arch_debug.cpp

@@ -29 +29 @@
 
 #define NUM_PREVIOUS_LOCATIONS 32
-
-extern struct iframe_stack gBootFrameStack;
 
 
@@ -201 +199 @@
 is_iframe(struct thread* thread, addr_t frame)
 {
-        return is_kernel_stack_address(thread, frame)
-                && (*(addr_t*)frame & ~IFRAME_TYPE_MASK) == 0;
+        if (!is_kernel_stack_address(thread, frame))
+                return false;
+
+        addr_t previousFrame = *(addr_t*)frame;
+        return ((previousFrame & ~IFRAME_TYPE_MASK) == 0 && previousFrame != 0);
 }
 

haiku/trunk/src/system/kernel/arch/x86/arch_thread.c

@@ -68 +68 @@
                 && frame < thread->kernel_stack_base + KERNEL_STACK_SIZE) {
                 addr_t previousFrame = *(addr_t*)frame;
-                if ((previousFrame & ~IFRAME_TYPE_MASK) == 0)
+                if ((previousFrame & ~IFRAME_TYPE_MASK) == 0) {
+                        if (previousFrame == 0)
+                                return NULL;
                         return (struct iframe*)frame;
+                }
 
                 frame = previousFrame;