From 3f353858c98dbe0240dac558a89870f4600f81bb Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Sun, 21 Dec 2008 22:48:32 +0200 Subject: 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 --- arch/x86/kvm/irq.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/x86/kvm/irq.h') diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h index b9e9051650ea..2bf32a03ceec 100644 --- a/arch/x86/kvm/irq.h +++ b/arch/x86/kvm/irq.h @@ -25,6 +25,7 @@ #include #include #include +#include #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; -- cgit v1.2.2