linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>,
	Alexey Dobriyan <adobriyan@gmail.com>,
	Peter Anvin <h.peter.anvin@intel.com>,
	kernel test robot <xiaolong.ye@intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Andrew Lutomirski <luto@kernel.org>,
	Borislav Petkov <bp@alien8.de>, Brian Gerst <brgerst@gmail.com>,
	Denys Vlasenko <dvlasenk@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Peter Anvin <hpa@zytor.com>, tipbuild@zytor.com, LKP <lkp@01.org>
Subject: Re: [lkp-robot] [x86/asm] 51bad67ffb: int3:#[##]
Date: Fri, 18 May 2018 09:15:59 +0200	[thread overview]
Message-ID: <20180518071559.GA26358@gmail.com> (raw)
In-Reply-To: <CA+55aFzTpkn_fokmm+ddi+cgk5K3EOftRmPad+NkUb5W2z0Fqg@mail.gmail.com>


* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Tue, May 15, 2018 at 3:43 PM Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> 
> > Glancing through the 32-bit and 64-bit entry code, I didn't see any more
> > cases.  At least it will fail loudly if any such cases do still exist.
> 
> \Will it? Do we have objtool checks for it now?
> 
> Because without static checks, there could be things hiding that just don't
> happen normally (think compat code etc that for most people is just dead
> code).

And it's not just about infrequent uses, it's also about hard to debug crashes 
like in suspend/resume code, where people can only report "machine is dead".

So I'm not sure this side effect of turning padding into crashes is good for 
overall robustness, without static analysis finding such bugs.

Thanks,

	Ingo

  parent reply	other threads:[~2018-05-18  7:16 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-15  8:00 [lkp-robot] [x86/asm] 51bad67ffb: int3:#[##] kernel test robot
2018-05-15 21:07 ` Alexey Dobriyan
     [not found]   ` <C40DC70F50313144AB3AF8625D4F407F90689B42@ORSMSX101.amr.corp.intel.com>
2018-05-15 21:43     ` Alexey Dobriyan
2018-05-15 22:22       ` Josh Poimboeuf
2018-05-15 22:26         ` Thomas Gleixner
2018-05-15 22:28         ` Linus Torvalds
2018-05-15 22:43           ` Josh Poimboeuf
2018-05-15 22:52             ` Linus Torvalds
2018-05-15 23:05               ` Linus Torvalds
2018-05-16  3:30                 ` Josh Poimboeuf
2018-05-17 13:49                   ` [PATCH] objtool: Detect assembly code falling through to INT3 padding Josh Poimboeuf
2018-05-17 14:01                     ` Peter Zijlstra
2018-05-18  7:24                       ` Ingo Molnar
2018-05-18  7:18                     ` Ingo Molnar
2018-05-18  7:27                       ` H. Peter Anvin
2018-05-18 16:06                         ` Borislav Petkov
2018-05-18  7:27                       ` Ingo Molnar
2018-05-18 17:51                       ` Alexey Dobriyan
2018-05-19  8:18                         ` hpa
2018-05-19  7:00                 ` "interesting" entry in hibernation code was Re: [lkp-robot] [x86/asm] 51bad67ffb: int3:#[##] Pavel Machek
2018-05-19  8:35                   ` Rafael J. Wysocki
2018-05-18  7:15               ` Ingo Molnar [this message]
2018-05-15 22:25       ` Thomas Gleixner
2018-05-15 22:29         ` Andy Lutomirski
2018-05-15 22:27       ` Linus Torvalds
2018-05-15 22:50         ` Alexey Dobriyan
2018-05-15 22:58           ` [PATCH v2] x86/asm: Pad assembly functions with INT3 instructions Alexey Dobriyan
2018-05-15 23:28             ` Linus Torvalds
2018-05-18  7:36             ` Ingo Molnar
2018-05-18 13:02               ` Josh Poimboeuf
2018-05-18 17:34                 ` Alexey Dobriyan

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=20180518071559.GA26358@gmail.com \
    --to=mingo@kernel.org \
    --cc=adobriyan@gmail.com \
    --cc=bp@alien8.de \
    --cc=brgerst@gmail.com \
    --cc=dvlasenk@redhat.com \
    --cc=h.peter.anvin@intel.com \
    --cc=hpa@zytor.com \
    --cc=jpoimboe@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lkp@01.org \
    --cc=luto@kernel.org \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --cc=tipbuild@zytor.com \
    --cc=torvalds@linux-foundation.org \
    --cc=xiaolong.ye@intel.com \
    /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).