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Date: Thu, 5 Jun 2014 10:58:45 +0100
From: Hani Benhabiles <kroosec@gmail.com>
Message-ID: <20140605095845.GA10811@Inspiron-3521>
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Subject: Re: [Qemu-devel] [PATCH 3/3] nbd: Shutdown socket before closing.
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: kwolf@redhat.com, famz@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com, mreitz@redhat.com

On Thu, Jun 05, 2014 at 03:55:40AM +0200, Paolo Bonzini wrote:
> Il 05/06/2014 00:33, Hani Benhabiles ha scritto:
> >> IIUC, what this does is ensure that the other side gets a FIN before it gets
> >> a RST.  Is this correct?
> >
> >Yes. Without shutdown(), this could be reproduced (unreliably) on multiple
> >tries. This is done in nbd_client_close() too, for the same reasons AFAICT.
> 
> Actually, nbd_client_close() is different because it's an abortive close of
> the socket.  nbd_client_close() doesn't care about FIN vs. RST, it does the
> shutdown to force all the requests to fail (with either an error for writes,
> or a short read if they're receiving).  This will cause a flurry of
> nbd_client_put() calls soon after nbd_clint_close() returns, until the last
> reference is dropped and the socket is closed.
> 

I see, thanks for the explanation.

> I'll apply the patch.

Will you apply it directly or should I resend it in v3 ?