From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] net: net_secret should not depend on TCP
Date: Tue, 24 Sep 2013 08:46:27 -0700
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Cc: Tom Herbert <therbert@google.com>, davem@davemloft.net,
	netdev@vger.kernel.org, jesse.brandeburg@intel.com
To: Hannes Frederic Sowa <hannes@stressinduktion.org>
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On Tue, 2013-09-24 at 17:28 +0200, Hannes Frederic Sowa wrote:

> But couldn't it be that get_random_bytes always returns 0 and we won't make
> any progress here. Does the reseed happen from irq context or from softirqs? I
> always thought it would be from a softirq (which could be blocked).

Really if get_random_bytes() could return 0 forever I think we would
have a big problem with its implementation and documentation :

/*
 * This function is the exported kernel interface.  It returns some
 * number of good random numbers, suitable for key generation, seeding
 * TCP sequence numbers, etc.  It does not use the hw random number
 * generator, if available; use get_random_bytes_arch() for that.
 */
void get_random_bytes(void *buf, int nbytes)
{
        extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0);
}
EXPORT_SYMBOL(get_random_bytes);