From: Linus Torvalds <torvalds@linux-foundation.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Arnaldo Carvalho de Melo <acme@infradead.org>,
Jiri Olsa <jolsa@redhat.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Mark Rutland <mark.rutland@arm.com>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [GIT PULL] perf fixes
Date: Fri, 1 Nov 2019 15:15:34 -0700 [thread overview]
Message-ID: <CAHk-=wg0tH4tf-YiviztA=8TpHsg-K_ERJW3t143uNnpkvCfWg@mail.gmail.com> (raw)
In-Reply-To: <20191101203048.GA6622@gmail.com>
On Fri, Nov 1, 2019 at 1:30 PM Ingo Molnar <mingo@kernel.org> wrote:
>
> Firstly, non-existent fields are initialized to zero by default in the
> perf ABI: *even if user-space was built well before that new field was
> introduced in the kernel*.
>
> This is done in perf_copy_attr():
>
> /* Zero the full structure, so that a short copy will be nice. */
> memset(attr, 0, sizeof(*attr));
>
> The user-space structure that is passed in ('uattr' within that function)
> might indeed be short and not contain the new field - but we handle this
> via uattr->size, which is set by user-space - for example 'perf' sets it
> in event_attr_init() in tools/perf/util/util.c:
>
> /* to capture ABI version */
> attr->size = sizeof(*attr);
>
> Second, the kernel syscall then checks this size against the kernel's
> size of attr:
>
> - if uattr->size < kattr_size: then old ABI user-space binary is
> running on new kernel, and we zero out residual fields.
Very good. These were the two pieces I was missing - just readfing the
commit messages it wasn't clear that this was safe at all.
Thanks for following up on my worry,
Linus
next prev parent reply other threads:[~2019-11-01 22:15 UTC|newest]
Thread overview: 376+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-01 17:48 [GIT PULL] perf fixes Ingo Molnar
2019-11-01 18:48 ` Linus Torvalds
2019-11-01 20:30 ` Ingo Molnar
2019-11-01 21:01 ` Ingo Molnar
2019-11-01 22:15 ` Linus Torvalds [this message]
2019-11-01 19:10 ` pr-tracker-bot
-- strict thread matches above, loose matches on Subject: below --
2023-01-06 11:57 Ingo Molnar
2023-01-06 21:19 ` pr-tracker-bot
2022-10-02 10:56 Ingo Molnar
2022-10-02 16:47 ` Linus Torvalds
2022-10-03 10:55 ` Ingo Molnar
2022-10-02 17:20 ` pr-tracker-bot
2022-08-28 14:35 Ingo Molnar
2022-08-28 18:18 ` pr-tracker-bot
2022-08-06 19:10 Ingo Molnar
2022-08-07 0:50 ` pr-tracker-bot
2021-07-11 13:26 Ingo Molnar
2021-07-11 18:22 ` pr-tracker-bot
2021-06-12 12:48 Ingo Molnar
2021-06-12 19:09 ` pr-tracker-bot
2021-03-21 10:56 Ingo Molnar
2021-03-21 18:45 ` pr-tracker-bot
2020-08-15 11:21 Ingo Molnar
2020-08-16 1:55 ` pr-tracker-bot
2020-04-25 9:19 Ingo Molnar
2020-04-25 19:30 ` pr-tracker-bot
2020-03-24 9:19 Ingo Molnar
2020-03-24 17:15 ` pr-tracker-bot
2020-03-02 7:23 Ingo Molnar
2020-03-03 23:35 ` pr-tracker-bot
2020-02-15 8:53 Ingo Molnar
2020-02-15 21:25 ` pr-tracker-bot
2020-01-18 17:58 Ingo Molnar
2020-01-18 21:05 ` pr-tracker-bot
2019-12-21 16:16 Ingo Molnar
2019-12-21 18:55 ` pr-tracker-bot
2019-12-17 11:34 Ingo Molnar
2019-12-17 19:06 ` Linus Torvalds
2019-12-18 6:58 ` Ingo Molnar
2019-12-17 19:20 ` pr-tracker-bot
2019-12-01 22:15 Ingo Molnar
2019-12-02 4:40 ` pr-tracker-bot
2019-11-16 21:33 Ingo Molnar
2019-11-17 0:35 ` pr-tracker-bot
2019-10-12 13:31 Ingo Molnar
2019-10-12 22:35 ` pr-tracker-bot
2019-07-14 12:01 Ingo Molnar
2019-07-14 18:45 ` pr-tracker-bot
2019-06-29 8:54 Ingo Molnar
2019-06-29 11:45 ` pr-tracker-bot
2019-06-02 17:39 Ingo Molnar
2019-06-02 18:15 ` pr-tracker-bot
2019-05-16 16:05 Ingo Molnar
2019-05-16 18:20 ` pr-tracker-bot
2019-05-05 12:47 Ingo Molnar
2019-05-05 22:10 ` pr-tracker-bot
2019-04-20 7:43 Ingo Molnar
2019-04-20 19:25 ` pr-tracker-bot
2019-04-12 13:06 Ingo Molnar
2019-04-13 4:05 ` pr-tracker-bot
2019-02-17 10:10 Ingo Molnar
2019-02-17 16:50 ` pr-tracker-bot
2019-02-10 9:01 Ingo Molnar
2019-02-10 18:30 ` pr-tracker-bot
2019-01-11 7:44 Ingo Molnar
2019-01-11 18:00 ` pr-tracker-bot
2018-11-30 6:25 Ingo Molnar
2018-11-30 21:00 ` pr-tracker-bot
2018-11-17 10:55 Ingo Molnar
2018-11-18 20:05 ` pr-tracker-bot
2018-10-20 8:10 Ingo Molnar
2018-10-20 13:28 ` Greg Kroah-Hartman
2018-10-11 9:12 Ingo Molnar
2018-10-11 12:32 ` Greg Kroah-Hartman
2018-10-11 8:59 Ingo Molnar
2018-10-05 9:42 Ingo Molnar
2018-10-05 9:55 ` Ingo Molnar
2018-10-05 23:30 ` Greg Kroah-Hartman
2018-09-15 13:11 Ingo Molnar
2018-07-30 17:53 Ingo Molnar
2018-07-13 19:59 Ingo Molnar
2018-06-30 8:44 Ingo Molnar
2018-06-04 9:04 Ingo Molnar
2018-03-31 10:40 Ingo Molnar
2018-03-25 8:53 Ingo Molnar
2018-02-06 21:29 Ingo Molnar
2017-12-06 22:17 Ingo Molnar
2017-11-26 12:40 Ingo Molnar
2017-11-05 14:40 Ingo Molnar
2017-11-09 8:13 ` Markus Trippelsdorf
2017-10-14 16:04 Ingo Molnar
2017-09-13 18:00 Ingo Molnar
2017-09-12 15:32 Ingo Molnar
2017-07-21 10:15 Ingo Molnar
2017-06-10 8:39 Ingo Molnar
2017-05-12 7:31 Ingo Molnar
2017-03-07 20:30 Ingo Molnar
2017-02-28 8:01 Ingo Molnar
2017-02-11 18:12 Ingo Molnar
2017-02-02 21:01 Ingo Molnar
2017-01-18 9:27 Ingo Molnar
2017-01-15 9:59 Ingo Molnar
2016-12-23 22:50 Ingo Molnar
2016-12-07 18:45 Ingo Molnar
2016-11-23 9:00 Ingo Molnar
2016-11-14 7:56 Ingo Molnar
2016-10-28 19:41 Ingo Molnar
2016-10-18 11:07 Ingo Molnar
2016-09-13 18:14 Ingo Molnar
2016-08-18 20:38 Ingo Molnar
2016-08-12 19:35 Ingo Molnar
2016-07-26 14:13 Ingo Molnar
2016-07-08 13:42 Ingo Molnar
2016-06-10 12:50 Ingo Molnar
2016-05-13 18:51 Ingo Molnar
2016-05-06 11:26 Ingo Molnar
2016-04-28 17:56 Ingo Molnar
2016-04-03 11:00 Ingo Molnar
2016-02-20 11:14 Ingo Molnar
2016-01-14 10:03 Ingo Molnar
2016-01-08 12:46 Ingo Molnar
2015-12-08 4:22 Ingo Molnar
2015-09-17 8:02 Ingo Molnar
2015-09-02 18:11 Ingo Molnar
2015-08-22 12:19 Ingo Molnar
2015-08-14 7:12 Ingo Molnar
2015-07-18 2:53 Ingo Molnar
2015-07-06 15:29 Ingo Molnar
2015-06-13 14:29 Ingo Molnar
2015-06-05 8:37 Ingo Molnar
2015-05-15 7:17 Ingo Molnar
2015-05-06 12:52 Ingo Molnar
2015-04-03 13:11 Ingo Molnar
2015-03-17 16:48 Ingo Molnar
2015-03-01 17:00 Ingo Molnar
2015-02-20 13:40 Ingo Molnar
2015-01-30 18:44 Ingo Molnar
2015-01-17 14:15 Ingo Molnar
2015-01-11 8:42 Ingo Molnar
2014-11-20 7:46 Ingo Molnar
2014-10-31 11:13 Ingo Molnar
2014-11-03 9:02 ` Paul Bolle
2014-11-03 10:04 ` Peter Zijlstra
2014-09-19 10:46 Ingo Molnar
2014-08-24 20:25 Ingo Molnar
2014-07-16 11:11 Ingo Molnar
2014-06-18 16:39 Ingo Molnar
2014-05-22 8:04 Ingo Molnar
2014-05-01 6:34 Ingo Molnar
2014-04-20 8:02 Ingo Molnar
2014-04-19 10:41 Ingo Molnar
2014-04-16 13:04 Ingo Molnar
2014-03-22 9:06 Ingo Molnar
2014-03-16 16:34 Ingo Molnar
2014-03-02 8:51 Ingo Molnar
2014-02-22 19:16 Ingo Molnar
2014-02-09 8:01 Ingo Molnar
2014-01-25 7:30 Ingo Molnar
2014-01-19 12:08 Ingo Molnar
2013-12-19 16:52 Ingo Molnar
2013-12-02 14:39 Ingo Molnar
2013-11-15 19:46 Ingo Molnar
2013-11-01 9:56 Ingo Molnar
2013-10-29 10:04 Ingo Molnar
2013-10-26 12:24 Ingo Molnar
2013-10-28 8:28 ` Markus Trippelsdorf
2013-10-28 9:02 ` ------------------------------ Markus Trippelsdorf
2013-10-28 9:34 ` Markus Trippelsdorf
2013-10-28 12:34 ` Arnaldo Carvalho de Melo
2013-10-28 12:42 ` Arnaldo Carvalho de Melo
2013-10-28 12:59 ` Markus Trippelsdorf
2013-10-29 9:50 ` Stephane Eranian
2013-10-29 10:06 ` Ingo Molnar
2013-10-29 12:47 ` Arnaldo Carvalho de Melo
2013-10-08 12:12 Ingo Molnar
2013-09-28 18:03 Ingo Molnar
2013-09-29 11:47 ` Markus Trippelsdorf
2013-09-29 21:33 ` Andi Kleen
2013-09-29 22:47 ` Markus Trippelsdorf
2013-09-30 6:27 ` Ingo Molnar
2013-09-30 18:54 ` Andi Kleen
2013-10-01 8:42 ` Ingo Molnar
2013-09-25 18:00 Ingo Molnar
2013-09-18 16:06 Ingo Molnar
2013-09-12 13:38 Ingo Molnar
2013-09-12 18:03 ` Linus Torvalds
2013-09-12 18:10 ` Linus Torvalds
2013-09-12 18:43 ` Arnaldo Carvalho de Melo
2013-09-12 19:12 ` Arnaldo Carvalho de Melo
2013-09-12 19:13 ` Linus Torvalds
2013-09-12 19:55 ` Ingo Molnar
2013-09-12 19:58 ` David Ahern
2013-09-12 20:02 ` Arnaldo Carvalho de Melo
2013-09-12 20:31 ` Ingo Molnar
2013-09-12 20:43 ` Ingo Molnar
2013-09-12 20:18 ` Ingo Molnar
2013-09-12 20:38 ` Arnaldo Carvalho de Melo
2013-09-12 20:46 ` Ingo Molnar
2013-09-12 21:09 ` David Ahern
2013-09-12 21:18 ` Ingo Molnar
2013-09-12 22:10 ` David Ahern
2013-09-13 5:09 ` Ingo Molnar
2013-09-13 9:32 ` Jean Pihet
2013-09-13 9:45 ` Ingo Molnar
2013-09-13 17:15 ` Jean Pihet
2013-09-12 18:51 ` Linus Torvalds
2013-09-12 20:33 ` Ingo Molnar
2013-09-12 20:38 ` Linus Torvalds
2013-09-12 20:49 ` Ingo Molnar
2013-09-12 20:52 ` Linus Torvalds
2013-09-12 21:01 ` Ingo Molnar
2013-09-12 20:10 ` Ingo Molnar
2013-08-13 16:51 Ingo Molnar
2013-07-10 8:52 Ingo Molnar
2013-06-26 8:52 Ingo Molnar
2013-06-20 8:58 Ingo Molnar
2013-05-05 10:10 Ingo Molnar
2013-04-21 8:16 Ingo Molnar
2013-04-14 15:20 Ingo Molnar
2013-03-21 9:56 Ingo Molnar
2013-03-11 14:28 Ingo Molnar
2013-02-26 7:02 Ingo Molnar
2013-03-14 20:32 ` Linus Torvalds
2013-03-14 21:06 ` Linus Torvalds
2013-03-14 22:09 ` Stephane Eranian
2013-03-14 22:17 ` Linus Torvalds
2013-03-14 22:19 ` Stephane Eranian
2013-03-14 22:42 ` Stephane Eranian
2013-03-14 22:53 ` Stephane Eranian
2013-03-14 23:11 ` Stephane Eranian
2013-03-15 0:24 ` Stephane Eranian
2013-03-15 1:06 ` Linus Torvalds
2013-03-15 8:01 ` Stephane Eranian
2013-03-15 10:50 ` Stephane Eranian
2013-02-04 18:20 Ingo Molnar
2012-12-01 11:11 Ingo Molnar
2012-10-26 14:44 Ingo Molnar
2012-10-23 11:02 Ingo Molnar
2012-10-20 0:56 Ingo Molnar
2012-09-21 19:08 Ingo Molnar
2012-09-13 14:39 Ingo Molnar
2012-08-23 10:59 Ingo Molnar
2012-08-20 9:08 Ingo Molnar
2012-08-21 7:59 ` Ingo Molnar
2012-08-05 17:43 Ingo Molnar
2012-08-03 16:40 Ingo Molnar
2012-07-14 7:51 Ingo Molnar
2012-06-22 13:36 Ingo Molnar
2012-06-22 18:07 ` Linus Torvalds
2012-06-22 18:38 ` Hagen Paul Pfeifer
2012-06-22 18:52 ` Linus Torvalds
2012-06-22 19:06 ` Hagen Paul Pfeifer
2012-06-22 19:54 ` Steven Rostedt
[not found] ` <86448d73-2e19-416f-8104-ce72aa5d76eb@email.android.com>
2012-06-22 23:18 ` Steven Rostedt
2012-06-23 0:51 ` Arjan van de Ven
2012-06-23 1:57 ` Steven Rostedt
2012-06-23 18:25 ` H. Peter Anvin
2012-06-22 18:50 ` Steven Rostedt
2012-06-15 18:48 Ingo Molnar
2012-06-08 9:20 Ingo Molnar
2012-05-30 15:39 Ingo Molnar
2012-05-17 8:19 Ingo Molnar
2012-04-27 6:32 Ingo Molnar
2012-04-16 17:48 Ingo Molnar
2012-04-14 10:54 Ingo Molnar
2012-04-03 22:40 Ingo Molnar
2012-03-13 16:56 Ingo Molnar
2012-03-05 9:27 Ingo Molnar
2012-03-02 10:47 Ingo Molnar
2012-02-10 12:45 Ingo Molnar
2012-02-02 10:00 Ingo Molnar
2012-01-26 18:11 Ingo Molnar
2011-12-29 21:02 Ingo Molnar
2011-12-09 6:16 Ingo Molnar
2011-12-05 19:13 Ingo Molnar
2011-11-07 18:49 Ingo Molnar
2011-11-07 19:00 ` Linus Torvalds
2011-11-07 19:50 ` Ingo Molnar
2011-08-22 17:00 Ingo Molnar
2011-08-11 8:17 Ingo Molnar
2011-07-07 18:11 Ingo Molnar
2011-06-19 8:44 Ingo Molnar
2011-06-13 9:53 Ingo Molnar
2011-06-08 13:46 Ingo Molnar
2011-05-28 16:34 Ingo Molnar
2011-05-24 2:41 Ingo Molnar
2011-05-23 13:41 Ingo Molnar
2011-05-23 22:10 ` Eric Dumazet
2011-05-23 22:19 ` Frederic Weisbecker
2011-05-23 22:22 ` Eric Dumazet
2011-05-20 17:18 Ingo Molnar
2011-05-17 22:07 Ingo Molnar
2011-05-07 18:20 Ingo Molnar
2011-04-29 18:17 Ingo Molnar
2011-04-22 13:42 Ingo Molnar
2011-04-19 15:56 Ingo Molnar
2011-04-16 10:03 Ingo Molnar
2011-04-07 17:48 Ingo Molnar
2011-04-02 10:25 Ingo Molnar
2011-03-25 13:11 Ingo Molnar
2011-03-10 7:53 Ingo Molnar
2011-02-28 17:34 Ingo Molnar
2011-02-22 16:03 Ingo Molnar
2011-02-15 16:58 Ingo Molnar
2011-02-06 11:27 Ingo Molnar
2011-02-03 15:47 Ingo Molnar
2011-01-24 13:34 Ingo Molnar
2011-01-24 19:48 ` Linus Torvalds
2011-01-24 20:07 ` Ingo Molnar
2011-01-24 20:11 ` Ingo Molnar
2011-01-24 20:17 ` Ingo Molnar
2011-01-24 20:17 ` Linus Torvalds
2011-01-24 20:27 ` Linus Torvalds
2011-01-24 20:38 ` Arnaldo Carvalho de Melo
2011-01-24 21:13 ` Linus Torvalds
2011-01-24 21:25 ` Ingo Molnar
2011-01-24 22:00 ` Arnaldo Carvalho de Melo
2011-01-25 0:16 ` Ingo Molnar
2011-01-24 20:37 ` Davidlohr Bueso
2011-01-24 20:14 ` Arnaldo Carvalho de Melo
2011-01-18 18:59 Ingo Molnar
2011-01-18 9:42 Ingo Molnar
2011-01-15 15:24 Ingo Molnar
2011-01-11 11:32 Ingo Molnar
2011-01-03 19:04 Ingo Molnar
2010-12-23 12:56 Ingo Molnar
2010-12-19 15:34 Ingo Molnar
2010-12-08 7:55 Ingo Molnar
2010-11-28 17:36 Ingo Molnar
2010-11-26 13:20 Ingo Molnar
2010-11-11 10:38 Ingo Molnar
2010-10-30 18:21 Ingo Molnar
2010-10-13 15:21 Ingo Molnar
2010-10-05 14:49 Ingo Molnar
2010-09-26 8:38 Ingo Molnar
2010-09-21 19:39 Ingo Molnar
2010-09-10 14:26 Ingo Molnar
2010-08-25 17:44 Ingo Molnar
2010-08-24 19:06 Ingo Molnar
2010-08-19 14:55 Ingo Molnar
2010-08-18 8:14 Ingo Molnar
2010-07-23 19:41 Ingo Molnar
2010-07-16 17:30 Ingo Molnar
2010-07-08 4:36 Frederic Weisbecker
2010-07-08 4:40 ` Frederic Weisbecker
2010-07-08 6:36 ` Ingo Molnar
2010-07-04 20:24 Ingo Molnar
2010-06-10 10:25 Ingo Molnar
2010-06-02 12:28 Ingo Molnar
2010-05-31 23:02 Frederic Weisbecker
2010-06-01 6:59 ` Ingo Molnar
2010-05-30 19:27 Ingo Molnar
2010-05-20 9:44 Frederic Weisbecker
2010-05-20 12:40 ` Ingo Molnar
2010-05-11 19:18 Ingo Molnar
2010-05-12 0:39 ` Linus Torvalds
2010-04-06 17:49 Ingo Molnar
2010-04-04 10:15 Ingo Molnar
2010-04-03 10:47 Frederic Weisbecker
2010-03-28 5:11 Frederic Weisbecker
2010-03-29 3:33 ` Ingo Molnar
2010-03-26 15:16 Ingo Molnar
2010-03-16 16:06 Ingo Molnar
2010-03-11 19:12 Ingo Molnar
2010-02-22 16:50 Ingo Molnar
2010-02-22 17:01 ` Linus Torvalds
2010-02-22 17:15 ` Frederic Weisbecker
2010-02-14 9:06 Ingo Molnar
2010-01-31 17:32 Ingo Molnar
2010-01-21 15:38 Ingo Molnar
2009-12-31 12:00 Ingo Molnar
2009-12-18 18:59 Ingo Molnar
2009-09-22 7:51 Ingo Molnar
2009-09-22 14:49 ` Linus Torvalds
2009-09-22 14:59 ` Ingo Molnar
2009-09-22 15:13 ` Linus Torvalds
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='CAHk-=wg0tH4tf-YiviztA=8TpHsg-K_ERJW3t143uNnpkvCfWg@mail.gmail.com' \
--to=torvalds@linux-foundation.org \
--cc=a.p.zijlstra@chello.nl \
--cc=acme@infradead.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=jolsa@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mingo@kernel.org \
--cc=tglx@linutronix.de \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.