This patch resulted from a security review of coreboot's SMM handler.
Feedback appreciated.
Regards,
Stefan
- fix SMM code relocation race
- make SMM relocation debugging Kconfig accessible
Signed-off-by: Stefan Reinauer <ste...@coresystems.de>
Index: src/southbridge/intel/i82801dx/i82801dx_smi.c
===================================================================
--- src/southbridge/intel/i82801dx/i82801dx_smi.c (revision 5672)
+++ src/southbridge/intel/i82801dx/i82801dx_smi.c (working copy)
@@ -335,11 +335,13 @@
void smm_init(void)
{
- // FIXME is this a race condition?
- smm_relocate();
+ /* Put SMM code to 0xa0000 */
smm_install();
- // We're done. Make sure SMIs can happen!
+ /* Put relocation code to 0x38000 and relocate SMBASE */
+ smm_relocate();
+
+ /* We're done. Make sure SMIs can happen! */
smi_set_eos();
}
Index: src/southbridge/intel/i82801dx/i82801dx.h
===================================================================
--- src/southbridge/intel/i82801dx/i82801dx.h (revision 5672)
+++ src/southbridge/intel/i82801dx/i82801dx.h (working copy)
@@ -86,6 +86,7 @@
#define PCICMD 0x04
#define PMBASE 0x40
#define PMBASE_ADDR 0x0400
+#define DEFAULT_PMBASE PMBASE_ADDR
#define ACPI_CNTL 0x44
#define BIOS_CNTL 0x4E
#define GPIO_BASE 0x58
Index: src/southbridge/intel/i82801gx/i82801gx_smi.c
===================================================================
--- src/southbridge/intel/i82801gx/i82801gx_smi.c (revision 5672)
+++ src/southbridge/intel/i82801gx/i82801gx_smi.c (working copy)
@@ -335,11 +335,13 @@
void smm_init(void)
{
- // FIXME is this a race condition?
- smm_relocate();
+ /* Put SMM code to 0xa0000 */
smm_install();
- // We're done. Make sure SMIs can happen!
+ /* Put relocation code to 0x38000 and relocate SMBASE */
+ smm_relocate();
+
+ /* We're done. Make sure SMIs can happen! */
smi_set_eos();
}
Index: src/Kconfig
===================================================================
--- src/Kconfig (revision 5672)
+++ src/Kconfig (working copy)
@@ -560,6 +560,18 @@
If unsure, say N.
+config DEBUG_SMM_RELOCATION
+ bool "Debug SMM relocation code"
+ default n
+ depends on HAVE_SMI_HANDLER
+ help
+ This option enables additional SMM handler relocation related
+ debug messages.
+
+ Note: This option will increase the size of the coreboot image.
+
+ If unsure, say N.
+
config X86EMU_DEBUG
bool "Output verbose x86emu debug messages"
default n
Index: src/cpu/x86/smm/smmrelocate.S
===================================================================
--- src/cpu/x86/smm/smmrelocate.S (revision 5672)
+++ src/cpu/x86/smm/smmrelocate.S (working copy)
@@ -1,7 +1,7 @@
/*
* This file is part of the coreboot project.
*
- * Copyright (C) 2008 coresystems GmbH
+ * Copyright (C) 2008-2010 coresystems GmbH
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
@@ -24,13 +24,16 @@
// FIXME: Is this piece of code southbridge specific, or
// can it be cleaned up so this include is not required?
-// It's needed right now because we get our PM_BASE from
+// It's needed right now because we get our DEFAULT_PMBASE from
// here.
+#if defined(CONFIG_SOUTHBRIDGE_INTEL_I82801GX)
#include "../../../southbridge/intel/i82801gx/i82801gx.h"
+#elif defined(CONFIG_SOUTHBRIDGE_INTEL_I82801DX)
+#include "../../../southbridge/intel/i82801dx/i82801dx.h"
+#else
+#error "Southbridge needs SMM handler support."
+#endif
-#undef DEBUG_SMM_RELOCATION
-//#define DEBUG_SMM_RELOCATION
-
#define LAPIC_ID 0xfee00020
.global smm_relocation_start
@@ -125,7 +128,7 @@
addr32 movl %eax, (%ebx)
- /* The next section of code is hardware specific */
+ /* The next section of code is potentially southbridge specific */
/* Clear SMI status */
movw $(DEFAULT_PMBASE + 0x34), %dx
@@ -143,8 +146,9 @@
orl $(1 << 1), %eax
outl %eax, %dx
- /* End of hardware specific section. */
-#ifdef DEBUG_SMM_RELOCATION
+ /* End of southbridge specific section. */
+
+#if defined(CONFIG_DEBUG_SMM_RELOCATION) && CONFIG_DEBUG_SMM_RELOCATION
/* print [SMM-x] so we can determine if CPUx went to SMM */
movw $CONFIG_TTYS0_BASE, %dx
mov $'[', %al
--
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