Re: [PATCH v6] arc4random: simplify design for better safety

From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>,
	Florian Weimer <fweimer@redhat.com>,
	Eric Biggers <ebiggers@kernel.org>,
	libc-alpha@sourceware.org, linux-crypto@vger.kernel.org
Subject: Re: [PATCH v6] arc4random: simplify design for better safety
Date: Thu, 28 Jul 2022 08:01:22 -0300	[thread overview]
Message-ID: <CAMXh4bW2gPP3nBaBUH-Rr2KTizuTPXD6wPYAdux=XU=iKRUaVg@mail.gmail.com> (raw)
In-Reply-To: <YuJmtY6agbe2pBSW@arm.com>

On Thu, Jul 28, 2022 at 7:37 AM Szabolcs Nagy via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> The 07/28/2022 11:29, Szabolcs Nagy via Libc-alpha wrote:
> > The 07/26/2022 21:58, Jason A. Donenfeld via Libc-alpha wrote:
> ...
> >
> > fyi, after this patch i see
> >
> > FAIL: stdlib/tst-arc4random-thread
> >
> > with
> >
> > $ cat stdlib/tst-arc4random-thread.out
> > info: arc4random: minimum of 1750000 blob results expected
> > info: arc4random: 1750777 blob results observed
> > info: arc4random_buf: minimum of 1750000 blob results expected
> > info: arc4random_buf: 1750000 blob results observed
> > info: arc4random_uniform: minimum of 1750000 blob results expected
> > Timed out: killed the child process
> > Termination time: 2022-07-27T14:41:33.766791947
> > Last write to standard output: 2022-07-27T14:41:22.522497854
> >
> > on an arm and aarch64 builder.
> >
> > running it manually it takes >30s to complete.
>
> note that before the patch it was <5s on the same machine.

Yeap, we need to tune down the internal test parameters [1].

[1] https://patchwork.sourceware.org/project/glibc/patch/20220727131031.2016648-1-adhemerval.zanella@linaro.org/