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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT 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 03200C43142 for ; Mon, 25 Jun 2018 13:19:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB22E25A4A for ; Mon, 25 Jun 2018 13:19:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BB22E25A4A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933829AbeFYNTj (ORCPT ); Mon, 25 Jun 2018 09:19:39 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:47244 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754582AbeFYNTh (ORCPT ); Mon, 25 Jun 2018 09:19:37 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4C9497C6A9; Mon, 25 Jun 2018 13:19:36 +0000 (UTC) Received: from treble (ovpn-123-175.rdu2.redhat.com [10.10.123.175]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 30C352166B5D; Mon, 25 Jun 2018 13:19:34 +0000 (UTC) Date: Mon, 25 Jun 2018 08:19:32 -0500 From: Josh Poimboeuf To: Ingo Molnar Cc: Alexey Dobriyan , Borislav Petkov , linux-crypto@vger.kernel.org, Mike Galbraith , torvalds@linux-foundation.org, tglx@linutronix.de, luto@kernel.org, peterz@infradead.org, brgerst@gmail.com, hpa@zytor.com, linux-kernel@vger.kernel.org, dvlasenk@redhat.com, h.peter.anvin@intel.com, linux-tip-commits , Herbert Xu , Peter Zijlstra Subject: Re: [PATCH] x86/crypto: Add missing RETs Message-ID: <20180625131932.sge43esxdb5ejoxg@treble> References: <1529235613.4572.7.camel@gmx.de> <20180617120012.GB16877@zn.tnic> <1529242717.4472.3.camel@gmx.de> <1529244178.4674.1.camel@gmx.de> <20180617194747.GA21160@zn.tnic> <1529289279.31745.3.camel@gmx.de> <20180623103622.GA2760@zn.tnic> <20180624071105.GA29407@gmail.com> <20180624104449.GA20159@avx2> <20180625072438.GA19063@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180625072438.GA19063@gmail.com> User-Agent: NeoMutt/20180323 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 25 Jun 2018 13:19:36 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Mon, 25 Jun 2018 13:19:36 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jpoimboe@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 25, 2018 at 09:24:38AM +0200, Ingo Molnar wrote: > > * Alexey Dobriyan wrote: > > > On Sun, Jun 24, 2018 at 09:11:05AM +0200, Ingo Molnar wrote: > > > > Add explicit RETs to the tail calls of AEGIS and MORUS crypto algorithms > > > > otherwise they run into INT3 padding due to > > > > > > > > 51bad67ffbce ("x86/asm: Pad assembly functions with INT3 instructions") > > > > > > > > leading to spurious debug exceptions. > > > > > > > > Mike Galbraith took care of all the remaining callsites. > > > > > > Note that 51bad67ffbce has been zapped because it caused too many problems like > > > this, but the explicit RETs make sense nevertheless. > > > > So commit which found real bug(s) was zapped. > > > > OK > > No, what happened is that the commit was first moved into WIP.x86/debug showing > its work-in-progress status, because it was incomplete and caused bugs: > > https://lore.kernel.org/lkml/20180518073644.GA8593@gmail.com/T/#u > > ... and finally, after weeks of inaction I zapped it because I didn't see progress > and you didn't answer my question. > > If a fixed patch with updated tooling to detect these crashes before they occur on > live systems is submitted we'll reconsider - it didn't get NAK-ed, it's just > incomplete in the current form. Hm, what happened to the objtool patch to detect these at build time? Did it not work? https://lore.kernel.org/lkml/20180517134934.eog2fgoby5azq5a7@treble -- Josh