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=-1.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 E6834C433DF for ; Thu, 14 May 2020 04:58:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C4584205CB for ; Thu, 14 May 2020 04:58:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589432286; bh=ddUrr9hDxrQIH4knLjpMqEzMT//jpgk9POSIeLe7uys=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=R+8Imdx8P6XzjUkJscNvwen4GMFT4HplduoaYzeTJOa/DLxWaHWOoo4mUmz/j8lTp 1H4Yf5+vQqPS8x+oTOPC/yCBWFjjPGtpSFFnDYxvT+SUsNxoJN64eNegKEotjGkBz1 cYk83ad3Giw+So4HMpKDHWMHe1xIEl4TGte9RKNA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726046AbgENE6G (ORCPT ); Thu, 14 May 2020 00:58:06 -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-Google-Smtp-Source: ABdhPJyzev78VR2eFEzu4QpBQY9fCsckfXycHjuyN1cID5gIUY7DfOPSBvhO6KI9OIPJwYzC51Emw003YwUrtGrNtHI= 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?