From e182c965b6ce0dffed0967a1be2173825a2ede2f Mon Sep 17 00:00:00 2001
From: Jeff Dike <jdike@addtoit.com>
Date: Fri, 8 Dec 2006 02:36:23 -0800
Subject: [PATCH] [PATCH] UML: add generic BUG support

The BUG changes in -mm3 need some arch support.  This patch adds the UML
support needed.  For the most part, it was stolen from the underlying
architecture.  The exception is the kernel eip < PAGE_OFFSET test, which is
wrong for skas mode UMLs.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
 arch/um/Kconfig             |  5 +++++
 arch/um/sys-i386/Makefile   |  2 +-
 arch/um/sys-i386/bug.c      | 20 ++++++++++++++++++++
 arch/um/sys-x86_64/Makefile |  2 +-
 arch/um/sys-x86_64/bug.c    | 20 ++++++++++++++++++++
 include/asm-um/bug.h        |  4 +++-
 6 files changed, 50 insertions(+), 3 deletions(-)
 create mode 100644 arch/um/sys-i386/bug.c
 create mode 100644 arch/um/sys-x86_64/bug.c

diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 5ac1f2963ae3..d32a80e6668c 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -47,6 +47,11 @@ config GENERIC_CALIBRATE_DELAY
 	bool
 	default y
 
+config GENERIC_BUG
+	bool
+	default y
+	depends on BUG
+
 # Used in kernel/irq/manage.c and include/linux/irq.h
 config IRQ_RELEASE_METHOD
 	bool
diff --git a/arch/um/sys-i386/Makefile b/arch/um/sys-i386/Makefile
index 0e32adf03be1..098720be019a 100644
--- a/arch/um/sys-i386/Makefile
+++ b/arch/um/sys-i386/Makefile
@@ -1,4 +1,4 @@
-obj-y = bugs.o checksum.o delay.o fault.o ksyms.o ldt.o ptrace.o \
+obj-y = bug.o bugs.o checksum.o delay.o fault.o ksyms.o ldt.o ptrace.o \
 	ptrace_user.o setjmp.o signal.o sigcontext.o syscalls.o sysrq.o \
 	sys_call_table.o tls.o
 
diff --git a/arch/um/sys-i386/bug.c b/arch/um/sys-i386/bug.c
new file mode 100644
index 000000000000..200c8ba2879b
--- /dev/null
+++ b/arch/um/sys-i386/bug.c
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2006 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL V2
+ */
+
+#include <linux/uaccess.h>
+
+/* Mostly copied from i386/x86_86 - eliminated the eip < PAGE_OFFSET because
+ * that's not relevent in skas mode.
+ */
+
+int is_valid_bugaddr(unsigned long eip)
+{
+	unsigned short ud2;
+
+	if (probe_kernel_address((unsigned short __user *)eip, ud2))
+		return 0;
+
+	return ud2 == 0x0b0f;
+}
diff --git a/arch/um/sys-x86_64/Makefile b/arch/um/sys-x86_64/Makefile
index f41768b8e25e..4d9e5efa6fb9 100644
--- a/arch/um/sys-x86_64/Makefile
+++ b/arch/um/sys-x86_64/Makefile
@@ -4,7 +4,7 @@
 # Licensed under the GPL
 #
 
-obj-y = bugs.o delay.o fault.o ldt.o mem.o ptrace.o ptrace_user.o \
+obj-y = bug.o bugs.o delay.o fault.o ldt.o mem.o ptrace.o ptrace_user.o \
 	setjmp.o sigcontext.o signal.o syscalls.o syscall_table.o sysrq.o \
 	ksyms.o tls.o
 
diff --git a/arch/um/sys-x86_64/bug.c b/arch/um/sys-x86_64/bug.c
new file mode 100644
index 000000000000..200c8ba2879b
--- /dev/null
+++ b/arch/um/sys-x86_64/bug.c
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2006 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL V2
+ */
+
+#include <linux/uaccess.h>
+
+/* Mostly copied from i386/x86_86 - eliminated the eip < PAGE_OFFSET because
+ * that's not relevent in skas mode.
+ */
+
+int is_valid_bugaddr(unsigned long eip)
+{
+	unsigned short ud2;
+
+	if (probe_kernel_address((unsigned short __user *)eip, ud2))
+		return 0;
+
+	return ud2 == 0x0b0f;
+}
diff --git a/include/asm-um/bug.h b/include/asm-um/bug.h
index 1e22fa26ff06..3357c5e2468e 100644
--- a/include/asm-um/bug.h
+++ b/include/asm-um/bug.h
@@ -1,4 +1,6 @@
 #ifndef __UM_BUG_H
 #define __UM_BUG_H
-#include <asm-generic/bug.h>
+
+#include <asm/arch/bug.h>
+
 #endif
-- 
2.20.1