From: Peter Zijlstra <peterz@infradead.org>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
arjan@linux.intel.com, bp@alien8.de,
richard.weinberger@gmail.com
Subject: Re: [PATCH] x86: Implement __WARN using UD0
Date: Thu, 23 Feb 2017 15:36:44 +0100 [thread overview]
Message-ID: <20170223143644.GD6515@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <20170223141232.nr6fahyhcljravbn@treble>
On Thu, Feb 23, 2017 at 08:12:32AM -0600, Josh Poimboeuf wrote:
> On Thu, Feb 23, 2017 at 02:28:13PM +0100, Peter Zijlstra wrote:
> > +/*
> > + * Only UD2 is defined in the Intel SDM and AMD64 docs,
> > + * but the interweb provided UD0 and UD1:
> > + *
> > + * https://groups.google.com/forum/#!topic/alt.os.assembly/_rS4L0fnqGE
>
> FYI, the latest Intel SDM does have UD0 and UD1.
Ooh, shiny, a new one.
> > + * Since various instruction decoders disagree on the length of UD1,
> > + * we cannot use it either. So use UD0 for WARN.
>
> It shows up as "(bad)" in objtool and gdb, though it still gets the
> length right:
>
> 8b9: 0f ff (bad)
>
> It would be nice if the tools knew about it...
Now that the SDM lists them, I suppose that's going to be any day now
:-)
next prev parent reply other threads:[~2017-02-23 14:37 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-23 13:28 [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra
2017-02-23 14:09 ` Peter Zijlstra
2017-02-23 14:59 ` Peter Zijlstra
2017-02-23 15:09 ` hpa
2017-02-23 15:23 ` Peter Zijlstra
2017-02-23 15:32 ` hpa
2017-02-23 16:03 ` Borislav Petkov
2017-02-23 14:12 ` Josh Poimboeuf
2017-02-23 14:17 ` Borislav Petkov
2017-02-23 14:36 ` Peter Zijlstra [this message]
2017-02-23 14:14 ` Arjan van de Ven
2017-02-23 14:57 ` Peter Zijlstra
2017-02-24 7:43 ` Ingo Molnar
2017-02-24 8:31 ` Peter Zijlstra
2017-02-24 9:06 ` hpa
2017-02-24 9:11 ` hpa
2017-02-24 9:15 ` Ingo Molnar
2017-02-24 9:46 ` Borislav Petkov
2017-02-24 9:52 ` H. Peter Anvin
[not found] ` <21ac6e53-2fcd-52e9-e72d-9faf7da14d1e@zytor.com>
2017-02-24 10:41 ` Peter Zijlstra
2017-02-25 10:38 ` Borislav Petkov
2017-02-25 17:55 ` hpa
2017-02-25 19:38 ` Borislav Petkov
2017-02-25 20:04 ` hpa
2017-02-25 20:29 ` Borislav Petkov
2017-02-24 11:16 ` [PATCH -v2] " Peter Zijlstra
2017-02-25 8:19 ` [RFC][PATCH] bug: Add _ONCE logic to report_bug() Peter Zijlstra
2017-02-25 9:18 ` Ingo Molnar
2017-02-25 9:44 ` Peter Zijlstra
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=20170223143644.GD6515@twins.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=arjan@linux.intel.com \
--cc=bp@alien8.de \
--cc=hpa@zytor.com \
--cc=jpoimboe@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=richard.weinberger@gmail.com \
--cc=tglx@linutronix.de \
--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