From 5955633e91bfc5cd0a41d8d82259e1d8b32980ef Mon Sep 17 00:00:00 2001
From: Michael D Labriola <michael.d.labriola@gmail.com>
Date: Sun, 29 Jan 2012 14:17:22 -0500
Subject: [PATCH] x86/reboot: Skip DMI checks if reboot set by user
Skip DMI checks for vendor specific reboot quirks if the user
passed in a reboot= arg on the command line - we should never
override user choices.
Signed-off-by: Michael D Labriola <michael.d.labriola@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Michael D Labriola <mlabriol@gdeb.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/87wr8ab9od.fsf@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
arch/x86/kernel/reboot.c | 28 ++++++++++++++++++++++++++--
1 file changed, 26 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 37a458b521a60..b257f0e288247 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -39,6 +39,14 @@ static int reboot_mode;
enum reboot_type reboot_type = BOOT_ACPI;
int reboot_force;
+/* This variable is used privately to keep track of whether or not
+ * reboot_type is still set to its default value (i.e., reboot= hasn't
+ * been set on the command line). This is needed so that we can
+ * suppress DMI scanning for reboot quirks. Without it, it's
+ * impossible to override a faulty reboot quirk without recompiling.
+ */
+static int reboot_default = 1;
+
#if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
static int reboot_cpu = -1;
#endif
@@ -67,6 +75,12 @@ bool port_cf9_safe = false;
static int __init reboot_setup(char *str)
{
for (;;) {
+ /* Having anything passed on the command line via
+ * reboot= will cause us to disable DMI checking
+ * below.
+ */
+ reboot_default = 0;
+
switch (*str) {
case 'w':
reboot_mode = 0x1234;
@@ -316,7 +330,12 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
static int __init reboot_init(void)
{
- dmi_check_system(reboot_dmi_table);
+ /* Only do the DMI check if reboot_type hasn't been overridden
+ * on the command line
+ */
+ if (reboot_default) {
+ dmi_check_system(reboot_dmi_table);
+ }
return 0;
}
core_initcall(reboot_init);
@@ -465,7 +484,12 @@ static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
static int __init pci_reboot_init(void)
{
- dmi_check_system(pci_reboot_dmi_table);
+ /* Only do the DMI check if reboot_type hasn't been overridden
+ * on the command line
+ */
+ if (reboot_default) {
+ dmi_check_system(pci_reboot_dmi_table);
+ }
return 0;
}
core_initcall(pci_reboot_init);
--
2.30.2