From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: [PATCH] kvm: fix ack not being delivered when msi present
Date: Sun, 26 Jul 2009 17:17:07 +0300
Message-ID: <20090726141707.GC30449@redhat.com>
References: <20090726141001.GA21167@redhat.com>
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Cc: avi@redhat.com, kvm@vger.kernel.org
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Sun, Jul 26, 2009 at 05:10:01PM +0300, Michael S. Tsirkin wrote:
> kvm_notify_acked_irq does not check irq type, so that it sometimes
> interprets msi vector as irq.  As a result, ack notifiers are not
> called, which typially hangs the guest.  The fix is to track and
> check irq type.
> 
Looks good to me.

> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Gleb Natapov <gleb@redhat.com>

> ---
> 
> Avi, since this bug was introduced in 2.6.30 already, I think
> we need the fix in 2.6.30.x as well as 2.6.31.
> 
>  include/linux/kvm_host.h |    1 +
>  virt/kvm/irq_comm.c      |    4 +++-
>  2 files changed, 4 insertions(+), 1 deletions(-)
> 
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index f244f11..f814512 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -119,6 +119,7 @@ struct kvm_memory_slot {
>  
>  struct kvm_kernel_irq_routing_entry {
>  	u32 gsi;
> +	u32 type;
>  	int (*set)(struct kvm_kernel_irq_routing_entry *e,
>  		    struct kvm *kvm, int level);
>  	union {
> diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
> index 100c267..001663f 100644
> --- a/virt/kvm/irq_comm.c
> +++ b/virt/kvm/irq_comm.c
> @@ -171,7 +171,8 @@ void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
>  	trace_kvm_ack_irq(irqchip, pin);
>  
>  	list_for_each_entry(e, &kvm->irq_routing, link)
> -		if (e->irqchip.irqchip == irqchip &&
> +		if (e->type == KVM_IRQ_ROUTING_IRQCHIP &&
> +		    e->irqchip.irqchip == irqchip &&
>  		    e->irqchip.pin == pin) {
>  			gsi = e->gsi;
>  			break;
> @@ -288,6 +289,7 @@ static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
>  	int delta;
>  
>  	e->gsi = ue->gsi;
> +	e->type = ue->type;
>  	switch (ue->type) {
>  	case KVM_IRQ_ROUTING_IRQCHIP:
>  		delta = 0;
> -- 
> 1.6.2.5

--
			Gleb.