linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Masahiro Yamada <masahiroy@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Michal Marek <michal.lkml@markovi.net>,
	linux-hardening@vger.kernel.org,
	Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Justin Forbes <jforbes@redhat.com>,
	Ondrej Mosnacek <omosnace@redhat.com>,
	Frank Eigler <fche@redhat.com>, Kees Cook <keescook@chromium.org>
Subject: Re: [PATCH RFC] gcc-plugins: Handle GCC version mismatch for OOT modules
Date: Sat, 6 Mar 2021 00:31:36 +0900	[thread overview]
Message-ID: <CAK7LNARDEwyjDj3u=8Y176TehU9FD548LFTrqi3AmBR6jrnA_Q@mail.gmail.com> (raw)
In-Reply-To: <CAHk-=wiT3FGuKuqLniBN2T_PZwD0GH4kf3XNCzq2tfChqn0+SQ@mail.gmail.com>

On Fri, Mar 5, 2021 at 4:13 AM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> On Thu, Mar 4, 2021 at 7:36 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
> >
> > All the kernel-space objects are rebuilt
> > when the compiler is upgraded.
>
> I very much NAK'ed that one. Why did that go in?


When the compiler is upgraded, all objects
should be rebuilt by the new compiler,
- this keeps Kbuild deterministic,
irrespective of whether it is a fresh build,
or incremental build.


If we do not force the full rebuild,
the banner at boot time is no point.

[    0.000000] Linux version 5.8.0-44-generic (buildd@lgw01-amd64-039)
(gcc (Ubuntu 10.2.0-13ubuntu1) 10.2.0, GNU ld (GNU Binutils for
Ubuntu) 2.35.1) #50-Ubuntu SMP Tue Feb 9 06:29:41 UTC 2021 (Ubuntu
5.8.0-44.50-generic 5.8.18)


It claims it was built by
gcc (Ubuntu 10.2.0-13ubuntu1) 10.2.0
but we would never know if it is true
for whole objects.
Some of them might have been compiled by
an older compiler.




> Or maybe I NAK'ed another version of it (I think the one I NAK'ed was
> from Josh), and didn't realize that there were multiple ones.
>
> > Linus complaint about GCC plugins not being rebuilt.
>
> Yes, and that was a separate complaint and not at all tied to the other objects.
>
> Gcc plugins aren't kernel object files at all. They are very much like
> dynamically loadable libraries to gcc itself.
>
>                Linus



-- 
Best Regards
Masahiro Yamada

  parent reply	other threads:[~2021-03-05 15:33 UTC|newest]

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-25 20:42 [PATCH RFC] gcc-plugins: Handle GCC version mismatch for OOT modules Josh Poimboeuf
2021-01-25 21:16 ` Masahiro Yamada
2021-01-25 21:27   ` Josh Poimboeuf
2021-01-25 21:44     ` Masahiro Yamada
2021-01-25 22:07       ` Josh Poimboeuf
2021-01-26  8:13         ` Greg KH
2021-01-26 12:44           ` Justin Forbes
2021-01-26 13:51             ` Greg KH
2021-01-26 14:51               ` Josh Poimboeuf
2021-01-26 15:00                 ` Greg KH
2021-01-26 15:15                 ` Peter Zijlstra
2021-01-26 15:46                   ` Josh Poimboeuf
2021-01-26 16:05                     ` Peter Zijlstra
2021-01-26 16:15                       ` Justin Forbes
2021-01-26 16:19                         ` Josh Poimboeuf
2021-01-26 17:06                           ` Greg KH
2021-01-26 17:47                             ` Justin Forbes
2021-01-26 16:22                       ` David Laight
2021-01-27 18:03             ` Christoph Hellwig
2021-01-26  8:12     ` Greg KH
2021-01-25 22:03 ` Kees Cook
2021-01-25 22:19   ` Josh Poimboeuf
2021-01-26 17:56     ` Kees Cook
2021-01-26 18:43       ` Josh Poimboeuf
2021-01-26 22:59         ` Kees Cook
2021-01-26 23:32           ` Josh Poimboeuf
2021-01-26  1:53   ` Masahiro Yamada
2021-01-26 12:16     ` David Laight
2021-01-27 18:02 ` Christoph Hellwig
2021-01-27 18:38   ` Josh Poimboeuf
2021-01-27 18:43     ` Christoph Hellwig
2021-01-27 18:51       ` Josh Poimboeuf
2021-01-27 22:09         ` David Laight
2021-01-28 14:29         ` Christoph Hellwig
2021-01-28 15:45           ` Josh Poimboeuf
2021-03-02 23:26 ` Josh Poimboeuf
2021-03-03 18:49   ` Masahiro Yamada
2021-03-03 19:15     ` Josh Poimboeuf
2021-03-03 19:25       ` Linus Torvalds
2021-03-03 19:38         ` Josh Poimboeuf
2021-03-03 19:57           ` Linus Torvalds
2021-03-03 20:24             ` Josh Poimboeuf
2021-03-03 20:31               ` Josh Poimboeuf
2021-03-03 20:56               ` Linus Torvalds
2021-03-03 21:45                 ` Josh Poimboeuf
2021-03-04 12:27                   ` Masahiro Yamada
2021-03-04 15:08                     ` Josh Poimboeuf
2021-03-04 15:35                       ` Masahiro Yamada
2021-03-04 19:12                         ` Linus Torvalds
2021-03-05  2:41                           ` Josh Poimboeuf
2021-03-05  2:49                             ` Linus Torvalds
2021-03-05 16:03                             ` Masahiro Yamada
2021-03-05 19:18                               ` Josh Poimboeuf
2021-03-08  9:39                                 ` David Laight
2021-03-05 15:31                           ` Masahiro Yamada [this message]
2021-03-03 21:52             ` Kees Cook
2021-03-04 12:26       ` Masahiro Yamada

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='CAK7LNARDEwyjDj3u=8Y176TehU9FD548LFTrqi3AmBR6jrnA_Q@mail.gmail.com' \
    --to=masahiroy@kernel.org \
    --cc=fche@redhat.com \
    --cc=jforbes@redhat.com \
    --cc=jpoimboe@redhat.com \
    --cc=keescook@chromium.org \
    --cc=linux-hardening@vger.kernel.org \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=michal.lkml@markovi.net \
    --cc=omosnace@redhat.com \
    --cc=peterz@infradead.org \
    --cc=torvalds@linux-foundation.org \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).