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=-1.1 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 86A75C38A2A for ; Fri, 8 May 2020 23:58:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 537CF217BA for ; Fri, 8 May 2020 23:58:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588982285; bh=YRqqtfHhUeECV3a07G0Ts+WJ74qbMuVFbkgCy+O7SN4=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=Qx+sUqBuY4TjOfDCs7JLSRa4mrn0k2TOaV/SMoY9my8N/bJfrByWF4jCRBKkxvUSN WEJraN8wqqR2Km5ga8JRPMudD+Y3AYghTc1k7CPXXTbU27Ns2IhrZor6kq3HjMT1Ml dIVk3tjfeO1KW0FRmkHSJRrQ9NL2qba5krWgrRMg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728231AbgEHX6E (ORCPT ); Fri, 8 May 2020 19:58:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:36656 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727778AbgEHX6E (ORCPT ); Fri, 8 May 2020 19:58:04 -0400 Received: from mail-wm1-f42.google.com (mail-wm1-f42.google.com [209.85.128.42]) (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 691662495C for ; Fri, 8 May 2020 23:58:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588982283; bh=YRqqtfHhUeECV3a07G0Ts+WJ74qbMuVFbkgCy+O7SN4=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=NIEuabiJEg2cqBqTSKuTtJFiPgB/n5LPuFcktX8Mcpgu56idVl2HZdoP++Hawge3z VmoIHxrHUvJiMyouM6wrw9GCaV2SSOqeaR9cN3Ygci7JgUP6+cEwALfhVuWC3PVluS v9qz0ANxiIjQQi0aFwvJ842DtJJI2qB4rovSVdfE= Received: by mail-wm1-f42.google.com with SMTP id m24so2342021wml.2 for ; Fri, 08 May 2020 16:58:03 -0700 (PDT) X-Gm-Message-State: AGi0PuYiZ+HYzUHd82O+7WfuWBZAa0JqIgFiKUzeyxZQ9LI2UOwc7nOZ tL2uMEBKSWhKFoOXyL3iH/crGn20vAjcnVcecxPXpg== X-Google-Smtp-Source: APiQypKQZNEwwX4h0fk2nHcrXKPOKkEGYndYO96klga8zo5b2LESL3vuvCxvl69OBwDucGzQm1kbDXFMs9oHRsA/5TA= X-Received: by 2002:a7b:c74d:: with SMTP id w13mr17955310wmk.36.1588982281881; Fri, 08 May 2020 16:58:01 -0700 (PDT) MIME-Version: 1.0 References: <20200505134112.272268764@linutronix.de> <20200505134340.703783926@linutronix.de> In-Reply-To: <20200505134340.703783926@linutronix.de> From: Andy Lutomirski Date: Fri, 8 May 2020 16:57:50 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [patch V4 part 2 06/18] x86/entry: Move irq flags tracing to prepare_exit_to_usermode() 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 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 7:14 AM Thomas Gleixner wrote: > > This is another step towards more C-code and less convoluted ASM. > > Similar to the entry path, invoke the tracer before context tracking which > might turn off RCU and invoke lockdep as the last step before going back to > user space. Annotate the code sections in exit_to_user_mode() accordingly > so objtool won't complain about the tracer invocation. Acked-by: Andy Lutomirski Note to self: the nmi code needs to be reworked to go through prepare_exit_to_usermode(), too. I'll do this once this whole pile lands.