linux-kernel - Re: [GIT PULL] x86 breakpoint regression fix

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 30 Jun 2010 21:04:08 +0200
From:	Frederic Weisbecker <fweisbec@...il.com>
To:	"Maciej W. Rozycki" <macro@...ux-mips.org>
Cc:	Ingo Molnar <mingo@...e.hu>, LKML <linux-kernel@...r.kernel.org>,
	Alexandre Julliard <julliard@...ehq.org>,
	"H . Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Prasad <prasad@...ux.vnet.ibm.com>,
	"2 . 6 . 33 . x 2 . 6 . 34 . x" <stable@...nel.org>
Subject: Re: [GIT PULL] x86 breakpoint regression fix

On Wed, Jun 30, 2010 at 03:40:51PM +0100, Maciej W. Rozycki wrote:
> On Wed, 30 Jun 2010, Frederic Weisbecker wrote:
> 
> >     - icebp/int01 trap. This instruction (0xf1) is undocumented and
> >       generates an int 1 exception. Unlike single step through TF
> >       flag, it doesn't set the single step origin of the exception
> >       in dr6.
> 
>  Not quite completely undocumented, but a bit obscure indeed.  GDB calls 
> this instruction ICEBP and some Intel sources -- INT1.  It's been around 
> for a while (at least since 80286) and is mostly used by in-circuit 
> emulators (hence the name GDB uses).


Right, in fact it was quite easy to find any documentation about it, it's
just officially undocumented.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/