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From: Anthony Liguori <anthony@codemonkey.ws>
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References: <74d06e1f94cc2337aa1bb6784a7ad2210ec55364.1364808312.git.amit.shah@redhat.com>
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Date: Wed, 03 Apr 2013 15:08:40 -0500
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Subject: Re: [Qemu-devel] [PATCH 1/1] rng backend: open backend in blocking
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To: Amit Shah <amit.shah@redhat.com>
Cc: qemu list <qemu-devel@nongnu.org>

Amit Shah <amit.shah@redhat.com> writes:

> On (Tue) 02 Apr 2013 [07:52:19], Anthony Liguori wrote:
>> Amit Shah <amit.shah@redhat.com> writes:
>> 
>> >> > backends/rng-random.c:44:entropy_available: assertion failed: (len != -1)
>> >> >
>> >> > without this fix.
>> >> 
>> >> This fix would cause QEMU to block indefinitely which I don't think is
>> >> very good behavior.  I think a better solution would be:
>
> How about relegating it to glib functions, and hooking it up so that
> /dev/random is polled for data, and this function gets called when
> /dev/random has data to give out?  Sure, when a read is attempted,
> there might be no data available again, but we could then go back to
> polling.

The fix I posted minus the needed s/EINTR/EAGAIN/g is pretty straight
forward and IMHO the proper way to handle this.

Is there something you think is broken with it?  I guess I should turn
it into a real patch but I was hoping you would so I didn't have to
recreate the original problem :-)

Regards,

Anthony Liguori

>
>
> 		Amit