linux-stable/arch/x86/kvm/irq.h
Peter Xu 654f1f13ea kvm: Check irqchip mode before assign irqfd
When assigning kvm irqfd we didn't check the irqchip mode but we allow
KVM_IRQFD to succeed with all the irqchip modes.  However it does not
make much sense to create irqfd even without the kernel chips.  Let's
provide a arch-dependent helper to check whether a specific irqfd is
allowed by the arch.  At least for x86, it should make sense to check:

- when irqchip mode is NONE, all irqfds should be disallowed, and,

- when irqchip mode is SPLIT, irqfds that are with resamplefd should
  be disallowed.

For either of the case, previously we'll silently ignore the irq or
the irq ack event if the irqchip mode is incorrect.  However that can
cause misterious guest behaviors and it can be hard to triage.  Let's
fail KVM_IRQFD even earlier to detect these incorrect configurations.

CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Radim Krčmář <rkrcmar@redhat.com>
CC: Alex Williamson <alex.williamson@redhat.com>
CC: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-05-24 21:27:12 +02:00

130 lines
3.5 KiB
C

/*
* irq.h: in kernel interrupt controller related definitions
* 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>
*
*/
#ifndef __IRQ_H
#define __IRQ_H
#include <linux/mm_types.h>
#include <linux/hrtimer.h>
#include <linux/kvm_host.h>
#include <linux/spinlock.h>
#include <kvm/iodev.h>
#include "ioapic.h"
#include "lapic.h"
#define PIC_NUM_PINS 16
#define SELECT_PIC(irq) \
((irq) < 8 ? KVM_IRQCHIP_PIC_MASTER : KVM_IRQCHIP_PIC_SLAVE)
struct kvm;
struct kvm_vcpu;
struct kvm_kpic_state {
u8 last_irr; /* edge detection */
u8 irr; /* interrupt request register */
u8 imr; /* interrupt mask register */
u8 isr; /* interrupt service register */
u8 priority_add; /* highest irq priority */
u8 irq_base;
u8 read_reg_select;
u8 poll;
u8 special_mask;
u8 init_state;
u8 auto_eoi;
u8 rotate_on_auto_eoi;
u8 special_fully_nested_mode;
u8 init4; /* true if 4 byte init */
u8 elcr; /* PIIX edge/trigger selection */
u8 elcr_mask;
u8 isr_ack; /* interrupt ack detection */
struct kvm_pic *pics_state;
};
struct kvm_pic {
spinlock_t lock;
bool wakeup_needed;
unsigned pending_acks;
struct kvm *kvm;
struct kvm_kpic_state pics[2]; /* 0 is master pic, 1 is slave pic */
int output; /* intr from master PIC */
struct kvm_io_device dev_master;
struct kvm_io_device dev_slave;
struct kvm_io_device dev_eclr;
void (*ack_notifier)(void *opaque, int irq);
unsigned long irq_states[PIC_NUM_PINS];
};
int kvm_pic_init(struct kvm *kvm);
void kvm_pic_destroy(struct kvm *kvm);
int kvm_pic_read_irq(struct kvm *kvm);
void kvm_pic_update_irq(struct kvm_pic *s);
static inline int pic_in_kernel(struct kvm *kvm)
{
int mode = kvm->arch.irqchip_mode;
/* Matches smp_wmb() when setting irqchip_mode */
smp_rmb();
return mode == KVM_IRQCHIP_KERNEL;
}
static inline int irqchip_split(struct kvm *kvm)
{
int mode = kvm->arch.irqchip_mode;
/* Matches smp_wmb() when setting irqchip_mode */
smp_rmb();
return mode == KVM_IRQCHIP_SPLIT;
}
static inline int irqchip_kernel(struct kvm *kvm)
{
int mode = kvm->arch.irqchip_mode;
/* Matches smp_wmb() when setting irqchip_mode */
smp_rmb();
return mode == KVM_IRQCHIP_KERNEL;
}
static inline int irqchip_in_kernel(struct kvm *kvm)
{
int mode = kvm->arch.irqchip_mode;
/* Matches smp_wmb() when setting irqchip_mode */
smp_rmb();
return mode != KVM_IRQCHIP_NONE;
}
bool kvm_arch_irqfd_allowed(struct kvm *kvm, struct kvm_irqfd *args);
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu);
void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu);
void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu);
void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu);
void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu);
void __kvm_migrate_timers(struct kvm_vcpu *vcpu);
int apic_has_pending_timer(struct kvm_vcpu *vcpu);
int kvm_setup_default_irq_routing(struct kvm *kvm);
int kvm_setup_empty_irq_routing(struct kvm *kvm);
#endif