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Date:   Tue, 17 Sep 2019 19:32:25 +0200
From:   Willy Tarreau <w@1wt.eu>
To:     Lennart Poettering <mzxreary@0pointer.de>
Cc:     "Alexander E. Patrakov" <patrakov@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Matthew Garrett <mjg59@srcf.ucam.org>,
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        zhangjs <zachary@baishancloud.com>, linux-ext4@vger.kernel.org,
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Subject: Re: Linux 5.3-rc8
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On Tue, Sep 17, 2019 at 07:30:36PM +0200, Lennart Poettering wrote:
> On Di, 17.09.19 21:58, Alexander E. Patrakov (patrakov@gmail.com) wrote:
> 
> > I am worried that the getrandom delays will be serialized, because processes
> > sometimes run one after another. If there are enough chained/dependent
> > processes that ask for randomness before it is ready, the end result is
> > still a too-big delay, essentially a failed boot.
> >
> > In other words: your approach of adding delays only makes sense for heavily
> > parallelized boot, which may not be the case, especially for embedded
> > systems that don't like systemd.
> 
> As mentioned elsewhere: once the pool is initialized it's
> initialized. This means any pending getrandom() on the whole system
> will unblock at the same time, and from the on all getrandom()s will
> be non-blocking.

He means that all process will experience this delay until there's enough
entropy.

Willy