From 7b3fd0f06fb373191146f27003ae529f1e67cf11 Mon Sep 17 00:00:00 2001
From: Jonas 'Sortie' Termansen <sortie@maxsi.org>
Date: Sat, 26 Jan 2013 00:15:15 +0100
Subject: [PATCH] Support doing kernel calltraces on another stack.

---
 sortix/calltrace.cpp   | 8 ++++----
 sortix/calltrace.h     | 6 ++++--
 sortix/x64/calltrace.s | 9 +++++++--
 sortix/x86/calltrace.s | 9 +++++++--
 4 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/sortix/calltrace.cpp b/sortix/calltrace.cpp
index d0a1d186..855d04b6 100644
--- a/sortix/calltrace.cpp
+++ b/sortix/calltrace.cpp
@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2012.
+    Copyright(C) Jonas 'Sortie' Termansen 2012, 2013.
 
     This file is part of Sortix.
 
@@ -28,16 +28,16 @@
 namespace Sortix {
 namespace Calltrace {
 
-extern "C" void calltrace();
+extern "C" void calltrace(unsigned long ptr);
 extern "C" void calltrace_print_function(size_t index, addr_t ip)
 {
 	Log::PrintF("%zu: 0x%zx\n", index, ip);
 }
 
-void Perform()
+void Perform(unsigned long ptr)
 {
 	Log::PrintF("Calltrace:\n");
-	calltrace();
+	calltrace(ptr);
 }
 
 } // namespace Calltrace
diff --git a/sortix/calltrace.h b/sortix/calltrace.h
index fefaf5ef..8ebfa420 100644
--- a/sortix/calltrace.h
+++ b/sortix/calltrace.h
@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2012.
+    Copyright(C) Jonas 'Sortie' Termansen 2012, 2013.
 
     This file is part of Sortix.
 
@@ -27,7 +27,9 @@
 
 namespace Sortix {
 namespace Calltrace {
-void Perform();
+
+void Perform(unsigned long ptr = 0);
+
 } // namespace Calltrace
 } // namespace Sortix
 
diff --git a/sortix/x64/calltrace.s b/sortix/x64/calltrace.s
index 418bf8d9..2cc976a2 100644
--- a/sortix/x64/calltrace.s
+++ b/sortix/x64/calltrace.s
@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012.
+    Copyright(C) Jonas 'Sortie' Termansen 2012, 2013.
 
     This file is part of Sortix.
 
@@ -31,8 +31,13 @@ calltrace:
 	push %rbp
 	push %rbx
 	movq %rsp, %rbp
-	xorl %edi, %edi
+	push %rbx
+	movq %rdi, %rbx
+	testq %rbx, %rbx
+	jnz 1f
 	movq %rbp, %rbx
+1:
+	xorl %edi, %edi
 
 calltrace_unwind:
 	testq %rbx, %rbx
diff --git a/sortix/x86/calltrace.s b/sortix/x86/calltrace.s
index 08647bc8..6df77f49 100644
--- a/sortix/x86/calltrace.s
+++ b/sortix/x86/calltrace.s
@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2011, 2012.
+    Copyright(C) Jonas 'Sortie' Termansen 2012, 2013.
 
     This file is part of Sortix.
 
@@ -31,8 +31,13 @@ calltrace:
 	push %ebp
 	push %ebx
 	movl %esp, %ebp
-	xorl %edi, %edi
+	push %ebx
+	movl 8(%ebp), %ebx
+	testl %ebx, %ebx
+	jnz 1f
 	movl %ebp, %ebx
+1:
+	xorl %edi, %edi
 
 calltrace_unwind:
 	testl %ebx, %ebx