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Date:   Mon, 30 May 2022 21:47:01 +0200
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Toralf =?utf-8?Q?F=C3=B6rster?= <toralf.foerster@gmx.de>
Cc:     Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: 5.18.1 has thousands of similar lines in dmesg with
 CONFIG_WARN_ALL_UNSEEDED_RANDOM=y
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Hi Toralf,

On Mon, May 30, 2022 at 11:24:55AM +0200, Toralf Förster wrote:
> This deletes the early boot messages in dmesg:
> 
> /var/log # head dmesg
> [    3.114274] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114286] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114291] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114297] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114304] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114315] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114323] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114329] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114333] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0
> [    3.114345] random: get_random_u32 called from
> allocate_slab+0x144/0x480 with crng_init=0

This was simplified here:

    https://lore.kernel.org/lkml/20220509172426.612649-1-Jason@zx2c4.com/
    https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cc1e127bfa95b5fb2f9307e7168bf8b2b45b4c5e

I'm happy to consider other heuristics than the one there if you find
this one problematic. But I think as a debug option, the current
behavior encapsulates well what somebody might want to know when
debugging a kernel. Either way, please let me know if this poses a
problem for you.

Jason