From: "Ahmed S. Darwish" <darwish.07@gmail.com> To: Linus Torvalds <torvalds@linux-foundation.org> Cc: Lennart Poettering <mzxreary@0pointer.de>, "Theodore Y. Ts'o" <tytso@mit.edu>, "Eric W. Biederman" <ebiederm@xmission.com>, "Alexander E. Patrakov" <patrakov@gmail.com>, Michael Kerrisk <mtk.manpages@gmail.com>, lkml <linux-kernel@vger.kernel.org>, linux-ext4@vger.kernel.org, linux-man@vger.kernel.org Subject: [PATCH RFC v4 0/1] random: WARN on large getrandom() waits and introduce getrandom2() Date: Wed, 18 Sep 2019 23:15:03 +0200 Message-ID: <20190918211503.GA1808@darwi-home-pc> (raw) In-Reply-To: <CAHk-=wgg2T=3KxrO-BY3nHJgMEyApjnO3cwbQb_0vxsn9qKN8Q@mail.gmail.com> Hi, This is an RFC, and it obviously needs much more testing beside the "it boots" smoke test I've just did. Interestingly though, on my current system, the triggered WARN() **reliably** makes the system get un-stuck... I know this is a very crude heuristic, but I would personally prefer it to the other proposals that were mentioned in this jumbo thread. If I get an OK from Linus on this, I'll send a polished v5: further real testing, kernel-parameters.txt docs, a new getrandom_wait(7) manpage as referenced in the WARN() message, and extensions to the getrandom(2) manpage for new getrandom2(). The new getrandom2() system call is basically a summary of Linus', Lennart's, and Willy's proposals. Please see the patch #1 commit log, and the "Link:" section inside it, for a rationale. @Lennart, since you obviously represent user-space here, any further notes on the new system call? thanks, Ahmed S. Darwish (1): random: WARN on large getrandom() waits and introduce getrandom2() drivers/char/Kconfig | 60 ++++++++++++++++++++++++-- drivers/char/random.c | 85 ++++++++++++++++++++++++++++++++----- include/uapi/linux/random.h | 20 +++++++-- 3 files changed, 148 insertions(+), 17 deletions(-) -- http://darwish.chasingpointers.com
next prev parent reply index Thread overview: 211+ messages / expand[flat|nested] mbox.gz Atom feed top [not found] <CAHk-=whBQ+6c-h+htiv6pp8ndtv97+45AH9WvdZougDRM6M4VQ@mail.gmail.com> 2019-09-10 4:21 ` Linux 5.3-rc8 Ahmed S. Darwish 2019-09-10 11:33 ` Linus Torvalds 2019-09-10 12:21 ` Linus Torvalds 2019-09-10 17:33 ` Ahmed S. Darwish 2019-09-10 17:47 ` Reindl Harald 2019-09-10 18:21 ` Linus Torvalds 2019-09-11 16:07 ` Theodore Y. Ts'o 2019-09-11 16:45 ` Linus Torvalds 2019-09-11 17:00 ` Linus Torvalds 2019-09-11 17:36 ` Theodore Y. Ts'o 2019-09-12 3:44 ` Ahmed S. Darwish 2019-09-12 8:25 ` Theodore Y. Ts'o 2019-09-12 11:34 ` Linus Torvalds 2019-09-12 11:58 ` Willy Tarreau 2019-09-14 12:25 ` [PATCH RFC] random: getrandom(2): don't block on non-initialized entropy pool Ahmed S. Darwish 2019-09-14 14:08 ` Alexander E. Patrakov 2019-09-15 5:22 ` [PATCH RFC v2] random: optionally block in getrandom(2) when the CRNG is uninitialized Theodore Y. Ts'o 2019-09-15 8:17 ` [PATCH RFC v3] random: getrandom(2): optionally block when " Ahmed S. Darwish 2019-09-15 8:59 ` Lennart Poettering 2019-09-15 9:30 ` Willy Tarreau 2019-09-15 10:02 ` Ahmed S. Darwish 2019-09-15 10:40 ` Willy Tarreau 2019-09-15 10:55 ` Ahmed S. Darwish 2019-09-15 11:17 ` Willy Tarreau 2019-09-15 17:32 ` [PATCH RFC v2] random: optionally block in getrandom(2) when the " Linus Torvalds 2019-09-15 18:32 ` Willy Tarreau 2019-09-15 18:36 ` Willy Tarreau 2019-09-15 19:08 ` Linus Torvalds 2019-09-15 19:18 ` Willy Tarreau 2019-09-15 19:31 ` Linus Torvalds 2019-09-15 19:54 ` Willy Tarreau 2019-09-15 18:59 ` Linus Torvalds 2019-09-15 19:12 ` Willy Tarreau 2019-09-16 2:45 ` Ahmed S. Darwish 2019-09-16 18:08 ` Lennart Poettering 2019-09-16 19:16 ` Willy Tarreau 2019-09-18 21:15 ` Ahmed S. Darwish [this message] 2019-09-18 21:17 ` [PATCH RFC v4 1/1] random: WARN on large getrandom() waits and introduce getrandom2() Ahmed S. Darwish 2019-09-18 23:57 ` Linus Torvalds 2019-09-19 14:34 ` Theodore Y. Ts'o 2019-09-19 15:20 ` Linus Torvalds 2019-09-19 15:50 ` Linus Torvalds 2019-09-20 13:13 ` Theodore Y. Ts'o 2019-09-19 20:04 ` Linus Torvalds 2019-09-19 20:45 ` Alexander E. Patrakov 2019-09-19 21:47 ` Linus Torvalds 2019-09-19 22:23 ` Alexander E. Patrakov 2019-09-19 23:44 ` Alexander E. Patrakov 2019-09-20 13:16 ` Theodore Y. Ts'o 2019-09-23 11:55 ` David Laight 2019-09-20 13:08 ` Theodore Y. Ts'o 2019-09-20 13:46 ` Ahmed S. Darwish 2019-09-20 14:33 ` Andy Lutomirski 2019-09-20 16:29 ` Linus Torvalds 2019-09-20 17:52 ` Andy Lutomirski 2019-09-20 18:09 ` Linus Torvalds 2019-09-20 18:16 ` Willy Tarreau 2019-09-20 19:12 ` Andy Lutomirski 2019-09-20 19:51 ` Linus Torvalds 2019-09-20 20:11 ` Alexander E. Patrakov 2019-09-20 20:17 ` Matthew Garrett 2019-09-20 20:51 ` Andy Lutomirski 2019-09-20 22:44 ` Linus Torvalds 2019-09-20 23:30 ` Andy Lutomirski 2019-09-21 3:05 ` Willy Tarreau 2019-09-21 6:07 ` Florian Weimer 2019-09-23 18:33 ` Andy Lutomirski 2019-09-26 21:11 ` Ahmed S. Darwish 2019-09-20 18:12 ` Willy Tarreau 2019-09-20 19:22 ` Andy Lutomirski 2019-09-20 19:37 ` Willy Tarreau 2019-09-20 19:52 ` Andy Lutomirski 2019-09-20 20:02 ` Linus Torvalds 2019-09-20 18:15 ` Alexander E. Patrakov 2019-09-20 18:29 ` Andy Lutomirski 2019-09-20 17:26 ` Willy Tarreau 2019-09-20 17:56 ` Ahmed S. Darwish 2019-09-26 20:42 ` [PATCH v5 0/1] random: getrandom(2): warn on large CRNG waits, introduce new flags Ahmed S. Darwish 2019-09-26 20:44 ` [PATCH v5 1/1] " Ahmed S. Darwish 2019-09-26 21:39 ` Andy Lutomirski 2019-09-28 9:30 ` Ahmed S. Darwish 2019-09-14 15:02 ` Linux 5.3-rc8 Ahmed S. Darwish 2019-09-14 16:30 ` Linus Torvalds 2019-09-14 16:35 ` Alexander E. Patrakov 2019-09-14 16:52 ` Linus Torvalds 2019-09-14 17:09 ` Alexander E. Patrakov 2019-09-14 19:19 ` Linus Torvalds 2019-09-15 6:56 ` Lennart Poettering 2019-09-15 7:01 ` Willy Tarreau 2019-09-15 7:05 ` Lennart Poettering 2019-09-15 7:07 ` Willy Tarreau 2019-09-15 8:34 ` Lennart Poettering 2019-09-15 17:02 ` Linus Torvalds 2019-09-16 3:23 ` Theodore Y. Ts'o 2019-09-16 3:40 ` Linus Torvalds 2019-09-16 3:56 ` Linus Torvalds 2019-09-16 17:00 ` Theodore Y. Ts'o 2019-09-16 17:07 ` Linus Torvalds 2019-09-14 21:11 ` Ahmed S. Darwish 2019-09-14 22:05 ` Martin Steigerwald 2019-09-14 22:24 ` Theodore Y. Ts'o 2019-09-14 22:32 ` Linus Torvalds 2019-09-15 1:00 ` Theodore Y. Ts'o 2019-09-15 1:10 ` Linus Torvalds 2019-09-15 2:05 ` Theodore Y. Ts'o 2019-09-15 2:11 ` Linus Torvalds 2019-09-15 6:33 ` Willy Tarreau 2019-09-15 6:53 ` Willy Tarreau 2019-09-15 6:51 ` Lennart Poettering 2019-09-15 7:27 ` Ahmed S. Darwish 2019-09-15 8:48 ` Lennart Poettering 2019-09-15 16:29 ` Linus Torvalds 2019-09-16 1:40 ` Ahmed S. Darwish 2019-09-16 1:48 ` Vito Caputo 2019-09-16 2:49 ` Theodore Y. Ts'o 2019-09-16 4:29 ` Willy Tarreau 2019-09-16 5:02 ` Linus Torvalds 2019-09-16 6:12 ` Willy Tarreau 2019-09-16 16:17 ` Linus Torvalds 2019-09-16 17:21 ` Theodore Y. Ts'o 2019-09-16 17:44 ` Linus Torvalds 2019-09-16 17:55 ` Serge Belyshev 2019-09-16 19:08 ` Willy Tarreau 2019-09-16 23:02 ` Matthew Garrett 2019-09-16 23:05 ` Linus Torvalds 2019-09-16 23:11 ` Matthew Garrett 2019-09-16 23:13 ` Alexander E. Patrakov 2019-09-16 23:15 ` Matthew Garrett 2019-09-16 23:18 ` Linus Torvalds 2019-09-16 23:29 ` Ahmed S. Darwish 2019-09-17 1:05 ` Linus Torvalds 2019-09-17 1:23 ` Matthew Garrett 2019-09-17 1:41 ` Linus Torvalds 2019-09-17 1:46 ` Matthew Garrett 2019-09-17 5:24 ` Willy Tarreau 2019-09-17 7:33 ` Martin Steigerwald 2019-09-17 8:35 ` Willy Tarreau 2019-09-17 8:44 ` Martin Steigerwald 2019-09-17 12:11 ` Theodore Y. Ts'o 2019-09-17 12:30 ` Ahmed S. Darwish 2019-09-17 12:46 ` Alexander E. Patrakov 2019-09-17 12:47 ` Willy Tarreau 2019-09-17 16:08 ` Lennart Poettering 2019-09-17 16:23 ` Linus Torvalds 2019-09-17 16:34 ` Reindl Harald 2019-09-17 17:42 ` Lennart Poettering 2019-09-17 18:01 ` Linus Torvalds 2019-09-17 20:28 ` Martin Steigerwald 2019-09-17 20:52 ` Ahmed S. Darwish 2019-09-17 21:38 ` Martin Steigerwald 2019-09-17 21:52 ` Matthew Garrett 2019-09-17 22:10 ` Martin Steigerwald 2019-09-18 13:53 ` Lennart Poettering 2019-09-19 7:28 ` Martin Steigerwald 2019-09-17 23:08 ` Linus Torvalds 2019-09-18 13:40 ` Lennart Poettering 2019-09-17 20:58 ` Linus Torvalds 2019-09-18 9:33 ` Rasmus Villemoes 2019-09-18 10:16 ` Willy Tarreau 2019-09-18 10:25 ` Alexander E. Patrakov 2019-09-18 10:42 ` Willy Tarreau 2019-09-18 19:31 ` Linus Torvalds 2019-09-18 19:56 ` Eric W. Biederman 2019-09-18 20:13 ` Linus Torvalds 2019-09-18 20:15 ` Alexander E. Patrakov 2019-09-18 20:26 ` Linus Torvalds 2019-09-18 22:12 ` Willy Tarreau 2019-09-27 13:57 ` Lennart Poettering 2019-09-27 15:58 ` Linus Torvalds 2019-09-29 9:05 ` Lennart Poettering 2019-09-17 13:11 ` Alexander E. Patrakov 2019-09-17 13:37 ` Alexander E. Patrakov 2019-09-17 15:57 ` Lennart Poettering 2019-09-17 16:21 ` Willy Tarreau 2019-09-17 17:13 ` Lennart Poettering 2019-09-17 17:29 ` Willy Tarreau 2019-09-17 20:42 ` Martin Steigerwald 2019-09-18 13:38 ` Lennart Poettering 2019-09-18 13:59 ` Alexander E. Patrakov 2019-09-18 14:50 ` Alexander E. Patrakov 2019-09-17 20:36 ` Martin Steigerwald 2019-09-17 16:27 ` Linus Torvalds 2019-09-17 16:34 ` Matthew Garrett 2019-09-17 17:16 ` Willy Tarreau 2019-09-17 17:20 ` Matthew Garrett 2019-09-17 17:23 ` Matthew Garrett 2019-09-17 17:57 ` Willy Tarreau 2019-09-17 16:58 ` Alexander E. Patrakov 2019-09-17 17:30 ` Lennart Poettering 2019-09-17 17:32 ` Willy Tarreau 2019-09-17 17:41 ` Alexander E. Patrakov 2019-09-17 17:28 ` Lennart Poettering 2019-09-17 0:03 ` Matthew Garrett 2019-09-17 0:40 ` Matthew Garrett 2019-09-17 7:15 ` a sane approach to random numbers (was: Re: Linux 5.3-rc8) Martin Steigerwald 2019-09-16 18:00 ` Linux 5.3-rc8 Alexander E. Patrakov 2019-09-16 19:53 ` Ahmed S. Darwish 2019-09-17 15:32 ` Lennart Poettering 2019-09-16 3:31 ` Linus Torvalds 2019-09-23 20:49 ` chaos generating driver was " Pavel Machek 2019-09-14 9:25 ` Ahmed S. Darwish 2019-09-14 16:27 ` Theodore Y. Ts'o 2019-09-11 21:41 ` Ahmed S. Darwish 2019-09-11 22:37 ` Ahmed S. Darwish 2019-09-16 3:52 ` Herbert Xu 2019-09-16 4:21 ` Linus Torvalds 2019-09-16 4:53 ` Willy Tarreau 2019-09-10 11:56 ` Theodore Y. Ts'o 2019-09-16 10:33 ` Christoph Hellwig 2019-10-03 21:10 ` Jon Masters 2019-10-03 21:31 ` Jon Masters
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20190918211503.GA1808@darwi-home-pc \ --to=darwish.07@gmail.com \ --cc=ebiederm@xmission.com \ --cc=linux-ext4@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-man@vger.kernel.org \ --cc=mtk.manpages@gmail.com \ --cc=mzxreary@0pointer.de \ --cc=patrakov@gmail.com \ --cc=torvalds@linux-foundation.org \ --cc=tytso@mit.edu \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
Linux-ext4 Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/linux-ext4/0 linux-ext4/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 linux-ext4 linux-ext4/ https://lore.kernel.org/linux-ext4 \ linux-ext4@vger.kernel.org public-inbox-index linux-ext4 Example config snippet for mirrors Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.linux-ext4 AGPL code for this site: git clone https://public-inbox.org/public-inbox.git