path: root/arch/x86/kvm/irq.h
diff options
authorAvi Kivity <avi@qumranet.com>2008-12-21 22:48:32 +0200
committerAvi Kivity <avi@redhat.com>2008-12-31 16:55:48 +0200
commit3f353858c98dbe0240dac558a89870f4600f81bb (patch)
tree95cdddb90777c332f747dfff041e1caf1fe78673 /arch/x86/kvm/irq.h
parent25e2343246fe135fce672f41abe61e9d2c38caac (diff)
KVM: Add locking to virtual i8259 interrupt controller
While most accesses to the i8259 are with the kvm mutex taken, the call to kvm_pic_read_irq() is not. We can't easily take the kvm mutex there since the function is called with interrupts disabled. Fix by adding a spinlock to the virtual interrupt controller. Since we can't send an IPI under the spinlock (we also take the same spinlock in an irq disabled context), we defer the IPI until the spinlock is released. Similarly, we defer irq ack notifications until after spinlock release to avoid lock recursion. Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/x86/kvm/irq.h')
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index b9e9051650e..2bf32a03cee 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -25,6 +25,7 @@
#include <linux/mm_types.h>
#include <linux/hrtimer.h>
#include <linux/kvm_host.h>
+#include <linux/spinlock.h>
#include "iodev.h"
#include "ioapic.h"
@@ -59,6 +60,10 @@ struct kvm_kpic_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 */
irq_request_func *irq_request;
void *irq_request_opaque;