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=-3.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 20993C35647 for ; Fri, 21 Feb 2020 13:50:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E8750208C4 for ; Fri, 21 Feb 2020 13:50:38 +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="cw08DLbJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728826AbgBUNuh (ORCPT ); Fri, 21 Feb 2020 08:50:37 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:56358 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728777AbgBUNud (ORCPT ); Fri, 21 Feb 2020 08:50:33 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-Id:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=VUxVM0zMD0yTdzXcfGzmRt1JL0NXbyE5uLB6keYVGUw=; b=cw08DLbJQYvhQZudJea9ctbBPs gZDQ7Tf8xRXC0YkkOMJ0ti+COpp4uB3qpocq0Q1nq2jpurVEI7n8MIXJNrGHV9FYzNmR8ZPIam9ny ZrvTrqLOXA4UwQVvXjnnTNJjrzaOgKNuEByWGsqr/9EHNbxrAGklvNOJf3w6+TTOPWrir9bpUKlXJ ldAMxpmdjEDnDHCKH5XKCrHK8LNskWewRk1E9/OWzzeTBPdBan0yCyJWHQCvpG2ZI5y/hnToERfZG hxC3SUAmZhWnW5+mJ0V28V4opOw6ghxT3zNjsxKlpYvDUqcCZnadIVYvU85jhTpRNIWgx/plgDzXC qlQNNI6Q==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1j58gt-0000OT-Nj; Fri, 21 Feb 2020 13:50:03 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 85E1D304D2C; Fri, 21 Feb 2020 14:48:07 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 0) id AFC5829B5903A; Fri, 21 Feb 2020 14:50:00 +0100 (CET) Message-Id: <20200221134215.206604505@infradead.org> User-Agent: quilt/0.65 Date: Fri, 21 Feb 2020 14:34:19 +0100 From: Peter Zijlstra To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, rostedt@goodmis.org Cc: peterz@infradead.org, mingo@kernel.org, joel@joelfernandes.org, gregkh@linuxfoundation.org, gustavo@embeddedor.com, tglx@linutronix.de, paulmck@kernel.org, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, luto@kernel.org, tony.luck@intel.com, frederic@kernel.org, dan.carpenter@oracle.com, mhiramat@kernel.org Subject: [PATCH v4 03/27] x86/entry: Flip _TIF_SIGPENDING and _TIF_NOTIFY_RESUME handling References: <20200221133416.777099322@infradead.org> MIME-Version: 1.0 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 Make sure we run task_work before we hit any kind of userspace -- very much including signals. Suggested-by: Andy Lutomirski Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/entry/common.c | 8 usr/src/linux-2.6/arch/x86/entry/common.c | 440 ------------------------------ 2 files changed, 4 insertions(+), 444 deletions(-) --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -155,16 +155,16 @@ static void exit_to_usermode_loop(struct if (cached_flags & _TIF_PATCH_PENDING) klp_update_patch_state(current); - /* deal with pending signal delivery */ - if (cached_flags & _TIF_SIGPENDING) - do_signal(regs); - if (cached_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); rseq_handle_notify_resume(NULL, regs); } + /* deal with pending signal delivery */ + if (cached_flags & _TIF_SIGPENDING) + do_signal(regs); + if (cached_flags & _TIF_USER_RETURN_NOTIFY) fire_user_return_notifiers();