From mboxrd@z Thu Jan  1 00:00:00 1970
From: Akio Takebe <takebe_akio@jp.fujitsu.com>
Subject: Re: hvm_set_callback_irq_level() deadlock?
Date: Wed, 07 Jan 2009 21:58:58 +0900
Message-ID: <4964A712.30407@jp.fujitsu.com>
References: <C58A34F8.20D09%keir.fraser@eu.citrix.com>
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To: Keir Fraser <keir.fraser@eu.citrix.com>
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Keir Fraser wrote:
> On 07/01/2009 10:22, "Akio Takebe" <takebe_akio@jp.fujitsu.com> wrote:
> 
>>> Doesn't vioapic_irq_positive_edge() clearly expect to be called with that
>>> lock held?
>> I concern about that vioapic_deliver() calls vcpu_kick(). If vcpu0 has the
>> lock and
>> vcpu1 cannot get lock and spin then vcpu0 sleep in another function,
>> it may cause deadlock because vioapic_irq_positive_edge() may call
>> vcpu_kick().
>> For example, the following function is OK?
> 
> I still don't see the problem. You'll have to spell out a concrete example,
> explaining where the two CPUs would be spinning and what state they're in
> (i.e, why they are depending on each other, and why no progress can be
> made).
> 
I thought more. Sorry, I was wrong.

Best Regards,

Akio Takebe