From mboxrd@z Thu Jan  1 00:00:00 1970
From: Radim =?utf-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>
Subject: Re: [PATCH v3 01/24] KVM: x86: race between KVM_SET_GSI_ROUTING and
 KVM_CREATE_IRQCHIP
Date: Tue, 25 Apr 2017 16:58:10 +0200
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Cc: Steve Rutherford <srutherford@google.com>,
        KVM list <kvm@vger.kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Peter Xu <peterx@redhat.com>
To: David Hildenbrand <david@redhat.com>
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2017-04-25 14:34+0200, David Hildenbrand:
> On 25.04.2017 00:39, Steve Rutherford wrote:
>> Sorry to resurrect this thread. There's an srcu_synchronize_expedited
>> call in kvm_set_irq_routing, so this lock might get held for a fairly
>> long while. Wouldn't it be a better idea to check the irqchip mode?
>> 
> 
> We could maybe check for kvm->arch.irqchip_mode == KVM_IRQCHIP_NONE
> here under lock instead of in the function itself. Maybe we then even
> don't need patch NR 2. Will have a look!

Sounds good and the extra mode would be obsolete.  Checking in
kvm_main.c will just need a new arch hook.  The patches are already in
kvm/next, though, so please prepare it as a fix.

Thanks.