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Date:   Thu, 30 Jul 2020 04:30:44 +0200
From:   Willy Tarreau <w@1wt.eu>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Stephen Rothwell <sfr@canb.auug.org.au>,
        Emese Revfy <re.emese@gmail.com>,
        Kees Cook <keescook@chromium.org>,
        Linux Next Mailing List <linux-next@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: linux-next: build failure after merge of the origin tree
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On Wed, Jul 29, 2020 at 07:12:58PM -0700, Linus Torvalds wrote:
> On Wed, Jul 29, 2020 at 5:09 PM Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > Removing the __latent_entropy marker obviously fixes things.
> 
> Ok, I did that for now. I spent a few minutes looking at the gcc
> plugin in case I'd be hit by some sudden stroke of genius, but that
> didn't happen, so let's avoid the issue until somebody who knows the
> gcc plugins better can come up with what the right solution is.

I've looked if we couldn't we work around this by declaring another
static variable with __latent_entropy and use it to initialize
net_rand_state early, for example in prandom_init(), but there we
already fill net_rand_state with randoms so I'm wondering if that
__latent_entropy is used before prandom_init() or if its sole purpose
is to provide extra initial entropy to be combined with the one
prandom_init() will add.

Willy