From: Linus Torvalds <torvalds@linux-foundation.org>
To: Willy Tarreau <w@1wt.eu>
Cc: George Spelvin <lkml@sdf.org>, Netdev <netdev@vger.kernel.org>,
Amit Klein <aksecurity@gmail.com>,
Eric Dumazet <edumazet@google.com>,
"Jason A. Donenfeld" <Jason@zx2c4.com>,
Andrew Lutomirski <luto@kernel.org>,
Kees Cook <keescook@chromium.org>,
Thomas Gleixner <tglx@linutronix.de>,
Peter Zijlstra <peterz@infradead.org>,
"Theodore Ts'o" <tytso@mit.edu>,
Marc Plumb <lkml.mplumb@gmail.com>,
Stephen Hemminger <stephen@networkplumber.org>,
Florian Westphal <fw@strlen.de>
Subject: Re: [DRAFT PATCH] random32: make prandom_u32() output unpredictable
Date: Mon, 10 Aug 2020 10:45:26 -0700 [thread overview]
Message-ID: <CAHk-=wiSbHyA3zpkNVf9G8uHDJ=JF12iUjMRH5h65DQf8VXDtg@mail.gmail.com> (raw)
In-Reply-To: <20200810165859.GD9060@1wt.eu>
On Mon, Aug 10, 2020 at 9:59 AM Willy Tarreau <w@1wt.eu> wrote:
>
> I took what we were already using in add_interrupt_randomness() since
> I considered that if it was acceptable there, it probably was elsewhere.
Once you've taken an interrupt, you're doing IO anyway, and the
interrupt costs will dominate anything you do.
But the prandom_u32() interface is potentially done many times per
interrupt. For all I know it's done inside fairly critical locks etc
too.
So I don't think one usage translates to another very well.
Linus
next prev parent reply other threads:[~2020-08-10 17:45 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-08 15:26 Flaw in "random32: update the net random state on interrupt and activity" George Spelvin
2020-08-08 17:07 ` Andy Lutomirski
2020-08-08 18:08 ` Willy Tarreau
2020-08-08 18:13 ` Linus Torvalds
2020-08-08 19:03 ` George Spelvin
2020-08-08 19:49 ` Andy Lutomirski
2020-08-08 21:29 ` George Spelvin
2020-08-08 17:44 ` Willy Tarreau
2020-08-08 18:19 ` Linus Torvalds
2020-08-08 18:53 ` Willy Tarreau
2020-08-08 20:47 ` George Spelvin
2020-08-08 20:52 ` Linus Torvalds
2020-08-08 22:27 ` George Spelvin
2020-08-09 2:07 ` Linus Torvalds
2020-08-11 16:01 ` Eric Dumazet
2020-08-08 19:18 ` Florian Westphal
2020-08-08 20:59 ` George Spelvin
2020-08-08 21:18 ` Willy Tarreau
2020-08-08 20:08 ` George Spelvin
2020-08-08 20:47 ` Linus Torvalds
2020-08-09 6:57 ` [DRAFT PATCH] random32: make prandom_u32() output unpredictable George Spelvin
2020-08-09 9:38 ` Willy Tarreau
2020-08-09 17:06 ` George Spelvin
2020-08-09 17:33 ` Willy Tarreau
2020-08-09 18:30 ` George Spelvin
2020-08-09 19:16 ` Willy Tarreau
2020-08-10 11:47 ` Willy Tarreau
2020-08-10 12:01 ` David Laight
2020-08-10 14:48 ` Willy Tarreau
2020-08-10 12:03 ` Florian Westphal
2020-08-10 14:53 ` Willy Tarreau
2020-08-10 16:31 ` Linus Torvalds
2020-08-10 16:58 ` Willy Tarreau
2020-08-10 17:45 ` Linus Torvalds [this message]
2020-08-10 18:01 ` Willy Tarreau
2020-08-10 21:04 ` Willy Tarreau
2020-08-11 5:26 ` George Spelvin
2020-08-11 5:37 ` Willy Tarreau
2020-08-11 3:47 ` George Spelvin
2020-08-11 3:58 ` Willy Tarreau
[not found] ` <fdbc7d7d-cba2-ef94-9bde-b3ccae0cfaac@gmail.com>
2020-08-09 21:10 ` Marc Plumb
2020-08-09 21:48 ` Linus Torvalds
2020-08-09 13:50 ` Randy Dunlap
[not found] ` <CANEQ_++a4YcwQQ2XhuguTono9=RxbSRVsMw08zLWBWJ_wxG2AQ@mail.gmail.com>
2020-08-09 16:08 ` George Spelvin
[not found] <CA+icZUVnsmf1kXPYFYufStQ_MxnLuxL+EWfDS2wQy1VbAEMwkA@mail.gmail.com>
2020-08-09 21:10 ` Sedat Dilek
[not found] ` <20200809235412.GD25124@SDF.ORG>
[not found] ` <20200810034948.GB8262@1wt.eu>
[not found] ` <20200811053455.GH25124@SDF.ORG>
[not found] ` <20200811054328.GD9456@1wt.eu>
[not found] ` <20200811062814.GI25124@SDF.ORG>
[not found] ` <20200811074538.GA9523@1wt.eu>
2020-08-11 10:51 ` Sedat Dilek
2020-08-11 11:01 ` Sedat Dilek
2020-08-12 3:21 ` Willy Tarreau
2020-08-13 7:53 ` Sedat Dilek
2020-08-13 8:06 ` Willy Tarreau
2020-08-13 8:13 ` Sedat Dilek
2020-08-13 8:27 ` Sedat Dilek
2020-08-13 14:00 ` Eric Dumazet
2020-08-13 16:02 ` Sedat Dilek
2020-08-14 15:32 ` Sedat Dilek
2020-08-14 16:05 ` Willy Tarreau
2020-08-14 16:17 ` Sedat Dilek
2020-08-16 15:01 ` Willy Tarreau
2020-08-16 16:48 ` Sedat Dilek
2020-08-20 3:05 ` Sedat Dilek
2020-08-20 4:33 ` Willy Tarreau
2020-08-20 4:42 ` Sedat Dilek
2020-08-20 6:08 ` Willy Tarreau
2020-08-20 6:58 ` Willy Tarreau
2020-08-20 8:05 ` Willy Tarreau
2020-08-20 12:08 ` Sedat Dilek
[not found] ` <CANEQ_+L+22Hkdqf38Zr0bfq16fcL1Ax2X9fToXV_niHKXCB8aA@mail.gmail.com>
2020-08-27 1:09 ` Willy Tarreau
2020-08-27 7:08 ` Sedat Dilek
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