There is no point in keeping the 8259A enabled if the I/O APIC NMI
watchdog has failed and the 8259A is not used to pass through regular
timer interrupts. This fixes problems with some systems where some logic
gets confused.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
---
patch-2.6.26-rc1-20080505-timer-8259-6
diff -up --recursive --new-file linux-2.6.26-rc1-20080505.macro/arch/x86/kernel/io_apic_32.c linux-2.6.26-rc1-20080505/arch/x86/kernel/io_apic_32.c
--- linux-2.6.26-rc1-20080505.macro/arch/x86/kernel/io_apic_32.c 2008-05-21 18:52:36.000000000 +0000
+++ linux-2.6.26-rc1-20080505/arch/x86/kernel/io_apic_32.c 2008-05-21 18:52:36.000000000 +0000
@@ -58,6 +58,7 @@ static struct { int pin, apic; } ioapic_
static DEFINE_SPINLOCK(ioapic_lock);
static DEFINE_SPINLOCK(vector_lock);
+int timer_through_8259 __initdata;
/*
* Is the SiS APIC rmw bug present ?
@@ -2194,6 +2195,7 @@ static inline void __init check_timer(vo
enable_8259A_irq(0);
if (timer_irq_works()) {
printk("works.\n");
+ timer_through_8259 = 1;
if (pin1 != -1)
replace_pin_at_irq(0, apic1, pin1, apic2, pin2);
else
diff -up --recursive --new-file linux-2.6.26-rc1-20080505.macro/arch/x86/kernel/io_apic_64.c linux-2.6.26-rc1-20080505/arch/x86/kernel/io_apic_64.c
--- linux-2.6.26-rc1-20080505.macro/arch/x86/kernel/io_apic_64.c 2008-05-18 00:24:43.000000000 +0000
+++ linux-2.6.26-rc1-20080505/arch/x86/kernel/io_apic_64.c 2008-05-18 00:24:43.000000000 +0000
@@ -90,6 +90,7 @@ static int no_timer_check;
static int disable_timer_pin_1 __initdata;
+int timer_through_8259 __initdata;
/* Where if anywhere is the i8259 connect in external int mode */
static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
@@ -1700,6 +1701,7 @@ static inline void __init check_timer(vo
enable_8259A_irq(0);
if (timer_irq_works()) {
apic_printk(APIC_VERBOSE," works.\n");
+ timer_through_8259 = 1;
nmi_watchdog_default();
if (nmi_watchdog == NMI_IO_APIC) {
...
