commit 5ca6c0ca5dbf105d7b0ffdae2289519982189730
author H. Peter Anvin <hpa@zytor.com> Mon Oct 12 14:12:18 2009 -0700
committer H. Peter Anvin <hpa@zytor.com> Mon Oct 12 14:19:35 2009 -0700
tree c9226c93c710f56b416545bad112b77047c4de32
parent a343c75d338aa2afaea4a2a8e40de9e67b6fb4a7

x86: use kernel_stack_pointer() in kgdb.c

The way to obtain a kernel-mode stack pointer from a struct
pt_regs in 32-bit mode is "subtle": the stack doesn't actually
contain the stack pointer, but rather the location where it would
have been marks the actual previous stack frame.  For clarity, use
kernel_stack_pointer() instead of coding this weirdness
explicitly.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jason Wessel <jason.wessel@windriver.com>

arch/x86/kernel/kgdb.c

diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index 8d82a77..3310d84 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -88,7 +88,6 @@
 	gdb_regs[GDB_SS]	= __KERNEL_DS;
 	gdb_regs[GDB_FS]	= 0xFFFF;
 	gdb_regs[GDB_GS]	= 0xFFFF;
-	gdb_regs[GDB_SP]	= (int)&regs->sp;
 #else
 	gdb_regs[GDB_R8]	= regs->r8;
 	gdb_regs[GDB_R9]	= regs->r9;
@@ -101,8 +100,8 @@
 	gdb_regs32[GDB_PS]	= regs->flags;
 	gdb_regs32[GDB_CS]	= regs->cs;
 	gdb_regs32[GDB_SS]	= regs->ss;
-	gdb_regs[GDB_SP]	= regs->sp;
 #endif
+	gdb_regs[GDB_SP]	= kernel_stack_pointer(regs);
 }
 
 /**