Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751677AbZIYKSQ (ORCPT ); Fri, 25 Sep 2009 06:18:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750901AbZIYKSO (ORCPT ); Fri, 25 Sep 2009 06:18:14 -0400 Received: from mtagate1.uk.ibm.com ([194.196.100.161]:58270 "EHLO mtagate1.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750907AbZIYKSO (ORCPT ); Fri, 25 Sep 2009 06:18:14 -0400 In-Reply-To: <20090925110206.50ab8a20@lxorguk.ukuu.org.uk> References: <20090924191642.GA19225@elte.hu> <20090924193422.GB2533@elte.hu> <20090925085119.2b77ea04@infradead.org> <20090925073512.GA10346@Krystal> <20090925110206.50ab8a20@lxorguk.ukuu.org.uk> Subject: Re: Immediate values X-KeepSent: 19654CE4:D069FD43-8025763C:0037FB4D; type=4; name=$KeepSent To: Alan Cox Cc: Andi Kleen , Anton Massoud , Arjan van de Ven , Dominique Toupin , "H. Peter Anvin" , Jason Baron , Jim Keniston , linux-kernel@vger.kernel.org, Mathieu Desnoyers , Masami Hiramatsu , Ingo Molnar , Nathan Sidwell , Prasanna S Panchamukhi , Steven Rostedt , Rusty Lynch , Suparna Bhattacharya , Thomas Gleixner , Vamsi Krishna S X-Mailer: Lotus Notes Release 8.5 December 05, 2008 Message-ID: From: Richard J Moore Date: Fri, 25 Sep 2009 11:18:07 +0100 X-MIMETrack: Serialize by Router on D06ML065/06/M/IBM(Release 8.0.1|February 07, 2008) at 25/09/2009 11:18:13 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1032 Lines: 30 Alan Cox wrote on 25/09/2009 11:02:06: > > There was considerable discussion abut this when the kprobe stuff went > in. If I remember rightly it was stated by someone @intel.com then that > int3 was ok (even though its not strictly documented as such). The same > is not true for all instructions on all x86 processors unfortunately. > > Alan Alan, I had that discussion with Intel, and yes int3 is a special case because of the interrupt processing associated with it. The discussion went along this lines: int3 is practically useless in an MP environment if it's trouble by the cross-modifying erratum. I suppose it is possible the more recent microarchitectures have changed things. And yes, we might need to have that conversation again. Richard -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/