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Date: Tue, 15 Jul 2014 17:21:21 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH for-2.1? 2/2] thread-pool: avoid deadlock
 in nested aio_poll() calls
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>, qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>

Il 15/07/2014 16:37, Stefan Hajnoczi ha scritto:
>> > This is of course missing here:
>> >
>> > 		break;
> Let's keep goto restart so we don't use the BH for each completion
> callback.  We just need the BH scheduled once to protect against the
> deadlock.

Ah, I missed this remark.

Then you could add qemu_bh_cancel at the end of the BH handler.  I do 
find the code a little harder to follow with the "goto" though, as it's 
not clear who will take care of the rest of the list...

Paolo