From: "Jan Beulich" <jbeulich@novell.com>
To: <mingo@elte.hu>, <tglx@linutronix.de>, <hpa@zytor.com>
Cc: <linux-kernel@vger.kernel.org>
Subject: [PATCH] x86: fully honor "nolapic"
Date: Wed, 14 Jan 2009 12:27:35 +0000 [thread overview]
Message-ID: <496DE847.76E4.0078.0@novell.com> (raw)
"nolapic" should not only suppress SMP and use of the LAPIC, but it
also ought to have the effect of disabling all IO-APIC related activity
as well as PCI MSI and HT-IRQs.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
---
arch/x86/kernel/apic.c | 7 ++++++-
arch/x86/kernel/io_apic.c | 6 ++++++
arch/x86/kernel/smpboot.c | 1 +
3 files changed, 13 insertions(+), 1 deletion(-)
--- linux-2.6.29-rc1/arch/x86/kernel/apic.c 2009-01-14 11:36:05.000000000 +0100
+++ 2.6.29-rc1-x86-no-lapic/arch/x86/kernel/apic.c 2009-01-13 14:57:59.000000000 +0100
@@ -1125,6 +1125,11 @@ void __cpuinit setup_local_APIC(void)
unsigned int value;
int i, j;
+ if (disable_apic) {
+ disable_ioapic_setup();
+ return;
+ }
+
#ifdef CONFIG_X86_32
/* Pound the ESR really hard over the head with a big hammer - mbligh */
if (lapic_is_integrated() && esr_disable) {
@@ -1565,11 +1570,11 @@ int apic_version[MAX_APICS];
int __init APIC_init_uniprocessor(void)
{
-#ifdef CONFIG_X86_64
if (disable_apic) {
pr_info("Apic disabled\n");
return -1;
}
+#ifdef CONFIG_X86_64
if (!cpu_has_apic) {
disable_apic = 1;
pr_info("Apic disabled by BIOS\n");
--- linux-2.6.29-rc1/arch/x86/kernel/io_apic.c 2009-01-14 11:36:05.000000000 +0100
+++ 2.6.29-rc1-x86-no-lapic/arch/x86/kernel/io_apic.c 2009-01-13 15:05:37.000000000 +0100
@@ -3258,6 +3258,9 @@ static int msi_compose_msg(struct pci_de
int err;
unsigned dest;
+ if (disable_apic)
+ return -ENXIO;
+
cfg = irq_cfg(irq);
err = assign_irq_vector(irq, cfg, TARGET_CPUS);
if (err)
@@ -3726,6 +3729,9 @@ int arch_setup_ht_irq(unsigned int irq,
struct irq_cfg *cfg;
int err;
+ if (disable_apic)
+ return -ENXIO;
+
cfg = irq_cfg(irq);
err = assign_irq_vector(irq, cfg, TARGET_CPUS);
if (!err) {
--- linux-2.6.29-rc1/arch/x86/kernel/smpboot.c 2009-01-14 11:36:05.000000000 +0100
+++ 2.6.29-rc1-x86-no-lapic/arch/x86/kernel/smpboot.c 2009-01-14 09:14:16.000000000 +0100
@@ -1125,6 +1125,7 @@ static int __init smp_sanity_check(unsig
printk(KERN_ERR "... forcing use of dummy APIC emulation."
"(tell your hw vendor)\n");
smpboot_clear_io_apic();
+ disable_ioapic_setup();
return -1;
}
next reply other threads:[~2009-01-14 12:27 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-14 12:27 Jan Beulich [this message]
2009-01-15 11:05 ` [PATCH] x86: fully honor "nolapic" Ingo Molnar
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