From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 887F5C43219 for ; Fri, 3 May 2019 16:33:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D45620651 for ; Fri, 3 May 2019 16:33:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ukMFMm5h" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728452AbfECQdd (ORCPT ); Fri, 3 May 2019 12:33:33 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:52484 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728429AbfECQdc (ORCPT ); Fri, 3 May 2019 12:33:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Transfer-Encoding :Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=7bDJVEAFBygjACU1RaANjjdiCUPrX9ag+EiTnO6DWPM=; b=ukMFMm5h9lQf5WvEOBr+T3kfZM r8r0CfSRKhD1HcNUjEmSwY8nkSDOrw/qrvpP5IUeaPWn0uqu+H8ujJnZijEzYL50HrovRcbh1KCPi Xi7YFpfcaHQCeyAOkmZqoJsDycMEA+JowfpGogZ7WT9RnZTuTBhhbvw6Unjh2xepqHmXA8ke/XDPd 2xluE4/HuIxcpEFNYoD8YMxvijgtfi8qb8wAkbgt2HmaiX2lMWoToHWt5nDMRuBiEmm+Fq+UnVyKY K7ysWZkcvWc8B11IHi5aHLYqcb16V8SSEPWf5W2vVXvX4KoNIZm8WziBlgUbZfv1FZ3vHiwdVed+K QryDkasA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1hMb7J-0005mB-Gk; Fri, 03 May 2019 16:32:57 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id B51CA286B6527; Fri, 3 May 2019 18:32:55 +0200 (CEST) Date: Fri, 3 May 2019 18:32:55 +0200 From: Peter Zijlstra To: Andy Lutomirski Cc: Steven Rostedt , Linus Torvalds , Linux List Kernel Mailing , Ingo Molnar , Andrew Morton , Andy Lutomirski , Nicolai Stange , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , the arch/x86 maintainers , Josh Poimboeuf , Jiri Kosina , Miroslav Benes , Petr Mladek , Joe Lawrence , Shuah Khan , Konrad Rzeszutek Wilk , Tim Chen , Sebastian Andrzej Siewior , Mimi Zohar , Juergen Gross , Nick Desaulniers , Nayna Jain , Masahiro Yamada , Joerg Roedel , "open list:KERNEL SELFTEST FRAMEWORK" , stable Subject: Re: [RFC][PATCH 1/2] x86: Allow breakpoints to emulate call functions Message-ID: <20190503163255.GG2606@hirez.programming.kicks-ass.net> References: <20190502181811.GY2623@hirez.programming.kicks-ass.net> <20190502202146.GZ2623@hirez.programming.kicks-ass.net> <20190502185225.0cdfc8bc@gandalf.local.home> <20190502193129.664c5b2e@gandalf.local.home> <20190502195052.0af473cf@gandalf.local.home> <20190503092959.GB2623@hirez.programming.kicks-ass.net> <20190503092247.20cc1ff0@gandalf.local.home> <2045370D-38D8-406C-9E94-C1D483E232C9@amacapital.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <2045370D-38D8-406C-9E94-C1D483E232C9@amacapital.net> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 03, 2019 at 09:20:55AM -0700, Andy Lutomirski wrote: > > On May 3, 2019, at 6:22 AM, Steven Rostedt wrote: > > > > On Fri, 3 May 2019 11:29:59 +0200 > > Peter Zijlstra wrote: > > > > > >> OMG, WTF, ARGH... That code is fsck'ing horrible. I'd almost argue to > >> always do the INT3 thing, just to avoid games like that. > So here’s a somewhat nutty suggestion: how about we tweak the 32-bit > entry code to emulate the sane 64-bit frame, not just for int3 but > always? Basically what I wrote above, right? I'd be fine with that... Linus?