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From: Eric Biggers <ebiggers@kernel.org>
To: "Guozihua (Scott)" <guozihua@huawei.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>,
	linux-crypto@vger.kernel.org, luto@kernel.org, tytso@mit.edu
Subject: Re: Inquiry about the removal of flag O_NONBLOCK on /dev/random
Date: Wed, 20 Jul 2022 23:50:46 -0700	[thread overview]
Message-ID: <Ytj3RnGtWqg18bxO@sol.localdomain> (raw)
In-Reply-To: <a93995db-a738-8e4f-68f2-42d7efd3c77d@huawei.com>

On Thu, Jul 21, 2022 at 02:44:54PM +0800, Guozihua (Scott) wrote:
> 
> Hi Eric
> 
> We have a userspace program that starts pretty early in the boot process and
> it tries to fetch random bits from /dev/random with O_NONBLOCK, if that
> returns -EAGAIN, it turns to /dev/urandom. Is this a correct handling of
> -EAGAIN? Or this is not one of the intended use case of O_NONBLOCK?

That doesn't make any sense; you should just use /dev/urandom unconditionally.

- Eric

  reply	other threads:[~2022-07-21  6:50 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-14  7:33 Inquiry about the removal of flag O_NONBLOCK on /dev/random Guozihua (Scott)
2022-07-18  8:52 ` Guozihua (Scott)
2022-07-19  3:47   ` Eric Biggers
2022-07-19  8:06     ` Guozihua (Scott)
2022-07-19 11:01 ` Jason A. Donenfeld
2022-07-21  3:50   ` Guozihua (Scott)
2022-07-21  4:07     ` Eric Biggers
2022-07-21  6:44       ` Guozihua (Scott)
2022-07-21  6:50         ` Eric Biggers [this message]
2022-07-21 10:37           ` Jason A. Donenfeld
2022-07-21 11:30             ` Guozihua (Scott)
2022-07-26  7:43             ` Guozihua (Scott)
2022-07-26 11:08               ` Jason A. Donenfeld
2022-07-26 11:33                 ` Guozihua (Scott)
2022-07-28  8:24                   ` Guozihua (Scott)
2022-09-06  7:14                     ` Guozihua (Scott)
2022-09-06 10:16                     ` Jason A. Donenfeld
2022-09-07 13:03                       ` Jason A. Donenfeld
2022-09-08  3:31                         ` Guozihua (Scott)
2022-09-08  9:51                           ` Jason A. Donenfeld
2022-09-08 10:40                             ` Jason A. Donenfeld
2022-09-08 14:26                               ` [PATCH] random: restore O_NONBLOCK support Jason A. Donenfeld
2022-09-19 10:27                             ` Inquiry about the removal of flag O_NONBLOCK on /dev/random Guozihua (Scott)
2022-09-19 10:40                               ` Jason A. Donenfeld
2022-09-19 10:45                                 ` Guozihua (Scott)
2022-07-21 11:09         ` Theodore Ts'o
2022-07-21 11:30           ` Guozihua (Scott)

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