mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-19 10:44:14 +08:00
3cf57fed21
The PIT injection logic is problematic under the following cases: 1) If there is a higher priority vector to be delivered by the time kvm_pit_timer_intr_post is invoked ps->inject_pending won't be set. This opens the possibility for missing many PIT event injections (say if guest executes hlt at this point). 2) ps->inject_pending is racy with more than two vcpus. Since there's no locking around read/dec of pt->pending, two vcpu's can inject two interrupts for a single pt->pending count. Fix 1 by using an irq ack notifier: only reinject when the previous irq has been acked. Fix 2 with appropriate locking around manipulation of pending count and irq_ack by the injection / ack paths. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
135 lines
3.3 KiB
C
135 lines
3.3 KiB
C
/*
|
|
* irq.c: API for in kernel interrupt controller
|
|
* Copyright (c) 2007, Intel Corporation.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
* more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along with
|
|
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
|
|
* Place - Suite 330, Boston, MA 02111-1307 USA.
|
|
* Authors:
|
|
* Yaozu (Eddie) Dong <Eddie.dong@intel.com>
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/kvm_host.h>
|
|
|
|
#include "irq.h"
|
|
#include "i8254.h"
|
|
|
|
/*
|
|
* check if there are pending timer events
|
|
* to be processed.
|
|
*/
|
|
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
|
|
{
|
|
int ret;
|
|
|
|
ret = pit_has_pending_timer(vcpu);
|
|
ret |= apic_has_pending_timer(vcpu);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
|
|
|
|
/*
|
|
* check if there is pending interrupt without
|
|
* intack.
|
|
*/
|
|
int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
|
|
{
|
|
struct kvm_pic *s;
|
|
|
|
if (kvm_apic_has_interrupt(v) == -1) { /* LAPIC */
|
|
if (kvm_apic_accept_pic_intr(v)) {
|
|
s = pic_irqchip(v->kvm); /* PIC */
|
|
return s->output;
|
|
} else
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
|
|
|
|
/*
|
|
* Read pending interrupt vector and intack.
|
|
*/
|
|
int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
|
|
{
|
|
struct kvm_pic *s;
|
|
int vector;
|
|
|
|
vector = kvm_get_apic_interrupt(v); /* APIC */
|
|
if (vector == -1) {
|
|
if (kvm_apic_accept_pic_intr(v)) {
|
|
s = pic_irqchip(v->kvm);
|
|
s->output = 0; /* PIC */
|
|
vector = kvm_pic_read_irq(v->kvm);
|
|
}
|
|
}
|
|
return vector;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
|
|
|
|
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
|
|
{
|
|
kvm_inject_apic_timer_irqs(vcpu);
|
|
kvm_inject_pit_timer_irqs(vcpu);
|
|
/* TODO: PIT, RTC etc. */
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
|
|
|
|
void kvm_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
|
|
{
|
|
kvm_apic_timer_intr_post(vcpu, vec);
|
|
/* TODO: PIT, RTC etc. */
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_timer_intr_post);
|
|
|
|
void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
|
|
{
|
|
__kvm_migrate_apic_timer(vcpu);
|
|
__kvm_migrate_pit_timer(vcpu);
|
|
}
|
|
|
|
/* This should be called with the kvm->lock mutex held */
|
|
void kvm_set_irq(struct kvm *kvm, int irq, int level)
|
|
{
|
|
/* Not possible to detect if the guest uses the PIC or the
|
|
* IOAPIC. So set the bit in both. The guest will ignore
|
|
* writes to the unused one.
|
|
*/
|
|
kvm_ioapic_set_irq(kvm->arch.vioapic, irq, level);
|
|
kvm_pic_set_irq(pic_irqchip(kvm), irq, level);
|
|
}
|
|
|
|
void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi)
|
|
{
|
|
struct kvm_irq_ack_notifier *kian;
|
|
struct hlist_node *n;
|
|
|
|
hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
|
|
if (kian->gsi == gsi)
|
|
kian->irq_acked(kian);
|
|
}
|
|
|
|
void kvm_register_irq_ack_notifier(struct kvm *kvm,
|
|
struct kvm_irq_ack_notifier *kian)
|
|
{
|
|
hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
|
|
}
|
|
|
|
void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
|
|
struct kvm_irq_ack_notifier *kian)
|
|
{
|
|
hlist_del(&kian->link);
|
|
}
|