Received: by 2002:a25:868d:0:0:0:0:0 with SMTP id z13csp1049395ybk; Wed, 13 May 2020 22:00:11 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyFY0AWQiFPx2hJ3HUne+wC6jpD6v1j0Yg7nXDe6jg7q7LtSbmiwmAM+fPWLTFp44B2u6+r X-Received: by 2002:a50:9b58:: with SMTP id a24mr2244724edj.256.1589432411127; Wed, 13 May 2020 22:00:11 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1589432411; cv=none; d=google.com; s=arc-20160816; b=ef++oGwzUo0UMVwmflF/7l0l5FWPLlLJByDay/qNqFX1a/5WaJcKLEhjB247d9vJc8 y4WQ82qdVFhzDRiul9k+V4N66yUpsQJHeMeq6cM0C1ILEhcSJUrAvtvf0ANp3DI1GjvB QrQ25dMKRQhr0TnON5HI4jhWyg5WbO4xS+YyvCRN+feac0qSjpIVmdHc9itsFS2ugPwW 9aen1AYGZDANARcmxWwsdhysqwGT2GaZmgy8BxyubixWXmuM39A4LAlQSCf73OFRSl29 aXoQX3JZWfCs62kKaSKjuD1hwgaEWusvWnAksoH0ARc+yIUFLfvTn55LnfjyULkhJMsf OqTQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:dkim-signature; bh=ddUrr9hDxrQIH4knLjpMqEzMT//jpgk9POSIeLe7uys=; b=As2Ux/E0BtsH10bsNuYbAhr2/KvOJ4l2oQpanchQYH4CNiCIBv9gtgwKwbOrF8Fbvq dhhsChmKfycPajuD0QaLdRnofEBgyoNVkNT7kmITfkLwUO2eu0hdkcjpfjALFuDwqw11 gTHEHUOWMQv2xGLWOM/c0zpQxb4TFPg01FQwPxphbPo5Wlyil9yxqTKAMKYzPtFBOYT3 aAd2mypFp9BFNSukGU+10p0kcOZgr2elGsSRXhJHKCc+/zuNx4VkroCJRL0mxYaLp3z8 S/0TbIveRC2S/qo2MNye1SJU8aCz8kkWk+LQa0dBF1VeoKFKySnEX7huuZAKcM47Ay// xmmw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=OPKI7rfr; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id do16si1410050ejc.265.2020.05.13.21.59.48; Wed, 13 May 2020 22:00:11 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=OPKI7rfr; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726033AbgENE6F (ORCPT + 99 others); Thu, 14 May 2020 00:58:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:40516 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725794AbgENE6F (ORCPT ); Thu, 14 May 2020 00:58:05 -0400 Received: from mail-wr1-f53.google.com (mail-wr1-f53.google.com [209.85.221.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E64F920760 for ; Thu, 14 May 2020 04:58:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589432285; bh=ddUrr9hDxrQIH4knLjpMqEzMT//jpgk9POSIeLe7uys=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=OPKI7rfrwk0FT5Juh68b6rV1OZT6nLgnH+rIs2CT2ZUmBgp0YzQUh2ds+q07WngyL zwS8GfyXA9XO8SNnZKgbCU4ZzbaNqygj+vNJtHcvua/7l8HOUzq7usoFFheLWtGPi6 lrCaHsGpE+f54hjMyKRCmdEdBaD/FbfbGvfKjyZg= Received: by mail-wr1-f53.google.com with SMTP id e1so2137496wrt.5 for ; Wed, 13 May 2020 21:58:04 -0700 (PDT) X-Gm-Message-State: AOAM530/q0hOtps4euV0XqiiFHzGSpOLbUJs2v+8/Lb+Cw9fjd25rVyS XoPBRmo07FXoL+ly+onhywTohVayrSjy3wi5/3Wi9g== X-Received: by 2002:adf:eccf:: with SMTP id s15mr3073367wro.70.1589432283319; Wed, 13 May 2020 21:58:03 -0700 (PDT) MIME-Version: 1.0 References: <20200505134926.578885807@linutronix.de> <20200505135313.517429268@linutronix.de> In-Reply-To: <20200505135313.517429268@linutronix.de> From: Andy Lutomirski Date: Wed, 13 May 2020 21:57:52 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [patch V4 part 4 02/24] x86/int3: Avoid atomic instrumentation To: Thomas Gleixner Cc: LKML , X86 ML , "Paul E. McKenney" , Andy Lutomirski , Alexandre Chartre , Frederic Weisbecker , Paolo Bonzini , Sean Christopherson , Masami Hiramatsu , Petr Mladek , Steven Rostedt , Joel Fernandes , Boris Ostrovsky , Juergen Gross , Brian Gerst , Mathieu Desnoyers , Josh Poimboeuf , Will Deacon , "Peter Zijlstra (Intel)" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 5, 2020 at 7:15 AM Thomas Gleixner wrote: > > From: Peter Zijlstra > > Use arch_atomic_*() and READ_ONCE_NOCHECK() to ensure nothing untoward > creeps in and ruins things. > > That is; this is the INT3 text poke handler, strictly limit the code > that runs in it, lest it inadvertenly hits yet another INT3. Acked-by: Andy Lutomirski Does objtool catch this error?