diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 5c0107602b625cae1827ab387b78edddb7a65f3d..e1f01394b681ab71e61a00570d6c04285c0ca2ae 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1373,8 +1373,6 @@ static void __init acpi_process_madt(void)
 	return;
 }
 
-#ifdef __i386__
-
 static int __init disable_acpi_irq(const struct dmi_system_id *d)
 {
 	if (!acpi_force) {
@@ -1435,6 +1433,17 @@ dmi_disable_irq0_through_ioapic(const struct dmi_system_id *d)
 	return 0;
 }
 
+/*
+ * Force ignoring BIOS IRQ0 pin2 override
+ */
+static int __init dmi_ignore_irq0_timer_override(const struct dmi_system_id *d)
+{
+	pr_notice("%s detected: Ignoring BIOS IRQ0 pin2 override\n", d->ident);
+	acpi_skip_timer_override = 1;
+	force_mask_ioapic_irq_2();
+	return 0;
+}
+
 /*
  * If your system is blacklisted here, but you find that acpi=force
  * works for you, please contact acpi-devel@sourceforge.net
@@ -1628,11 +1637,35 @@ static struct dmi_system_id __initdata acpi_dmi_table[] = {
 		     DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6325"),
 		     },
 	 },
+	/*
+	 * HP laptops which use a DSDT reporting as HP/SB400/10000,
+	 * which includes some code which overrides all temperature
+	 * trip points to 16C if the INTIN2 input of the I/O APIC
+	 * is enabled.  This input is incorrectly designated the
+	 * ISA IRQ 0 via an interrupt source override even though
+	 * it is wired to the output of the master 8259A and INTIN0
+	 * is not connected at all.  Force ignoring BIOS IRQ0 pin2
+	 * override in that cases.
+	 */
+	{
+	 .callback = dmi_ignore_irq0_timer_override,
+	 .ident = "HP NX6125 laptop",
+	 .matches = {
+		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		     DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6125"),
+		     },
+	 },
+	{
+	 .callback = dmi_ignore_irq0_timer_override,
+	 .ident = "HP NX6325 laptop",
+	 .matches = {
+		     DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+		     DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6325"),
+		     },
+	 },
 	{}
 };
 
-#endif				/* __i386__ */
-
 /*
  * acpi_boot_table_init() and acpi_boot_init()
  *  called from setup_arch(), always.
@@ -1660,9 +1693,7 @@ int __init acpi_boot_table_init(void)
 {
 	int error;
 
-#ifdef __i386__
 	dmi_check_system(acpi_dmi_table);
-#endif
 
 	/*
 	 * If acpi_disabled, bail out
diff --git a/arch/x86/kernel/io_apic_32.c b/arch/x86/kernel/io_apic_32.c
index 337ec3438a8f2f90655efa6c2a1e5419e8bd1000..6b220b9dcbb3d41bd87f126117977809bab5f812 100644
--- a/arch/x86/kernel/io_apic_32.c
+++ b/arch/x86/kernel/io_apic_32.c
@@ -59,6 +59,13 @@ static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
 static DEFINE_SPINLOCK(ioapic_lock);
 static DEFINE_SPINLOCK(vector_lock);
 
+static bool mask_ioapic_irq_2 __initdata;
+
+void __init force_mask_ioapic_irq_2(void)
+{
+	mask_ioapic_irq_2 = true;
+}
+
 int timer_through_8259 __initdata;
 
 /*
@@ -2172,6 +2179,9 @@ static inline void __init check_timer(void)
 	printk(KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
 		vector, apic1, pin1, apic2, pin2);
 
+	if (mask_ioapic_irq_2)
+		mask_IO_APIC_irq(2);
+
 	/*
 	 * Some BIOS writers are clueless and report the ExtINTA
 	 * I/O APIC input from the cascaded 8259A as the timer
diff --git a/arch/x86/kernel/io_apic_64.c b/arch/x86/kernel/io_apic_64.c
index 2b4c40bc12c9199c242f299dcb070ad06e7698de..0494cdb270c5c96e43e765bb8f659c871e018d04 100644
--- a/arch/x86/kernel/io_apic_64.c
+++ b/arch/x86/kernel/io_apic_64.c
@@ -94,6 +94,13 @@ static int no_timer_check;
 
 static int disable_timer_pin_1 __initdata;
 
+static bool mask_ioapic_irq_2 __initdata;
+
+void __init force_mask_ioapic_irq_2(void)
+{
+	mask_ioapic_irq_2 = true;
+}
+
 int timer_through_8259 __initdata;
 
 /* Where if anywhere is the i8259 connect in external int mode */
@@ -1698,6 +1705,9 @@ static inline void __init check_timer(void)
 	apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
 		cfg->vector, apic1, pin1, apic2, pin2);
 
+	if (mask_ioapic_irq_2)
+		mask_IO_APIC_irq(2);
+
 	/*
 	 * Some BIOS writers are clueless and report the ExtINTA
 	 * I/O APIC input from the cascaded 8259A as the timer
diff --git a/include/asm-x86/genapic_32.h b/include/asm-x86/genapic_32.h
index b02ea6e17de8b6a097c722f28d2c726f5e39514d..8d4c8bdb90656e74befb80957929694127ee695a 100644
--- a/include/asm-x86/genapic_32.h
+++ b/include/asm-x86/genapic_32.h
@@ -119,5 +119,6 @@ enum uv_system_type {UV_NONE, UV_LEGACY_APIC, UV_X2APIC, UV_NON_UNIQUE_APIC};
 #define is_uv_system()			0
 #define uv_wakeup_secondary(a, b)	1
 
+extern void force_mask_ioapic_irq_2(void);
 
 #endif
diff --git a/include/asm-x86/genapic_64.h b/include/asm-x86/genapic_64.h
index 0f8504627c41ce8c6d9f168e8ff038a8d15c3d12..082ad020e4127fed6f8ae8532f0298addf84efb2 100644
--- a/include/asm-x86/genapic_64.h
+++ b/include/asm-x86/genapic_64.h
@@ -46,4 +46,6 @@ extern int uv_wakeup_secondary(int phys_apicid, unsigned int start_rip);
 
 extern void setup_apic_routing(void);
 
+extern void force_mask_ioapic_irq_2(void);
+
 #endif