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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 DACC9C43603 for ; Wed, 18 Dec 2019 15:31:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9E77C24683 for ; Wed, 18 Dec 2019 15:31:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GPLGNJ8V" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727298AbfLRPbW (ORCPT ); Wed, 18 Dec 2019 10:31:22 -0500 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:25678 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726955AbfLRPbW (ORCPT ); Wed, 18 Dec 2019 10:31:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576683081; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=Nu4re5DJtt7kCRpoMSpCYfrOekqJ3V3x1aYPZ4h9ezM=; b=GPLGNJ8VqxrRQehKDyFJHAAeDFExArbuYh7eLBdfn8/pvoI85/+cW/wmG5xI3anu368JO4 5FUE78i/sZRkYm7JSr0e2Zo2VZ566AG0A/MBh9EOyHUx+CFb1zCC66t5LRAgzcYFtlTHxd mmfpNAI8pwBY5f+O5/9IvmKThGZhRL4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-265-wtG94tcuOXOJO92wC1j41w-1; Wed, 18 Dec 2019 10:31:15 -0500 X-MC-Unique: wtG94tcuOXOJO92wC1j41w-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 76893109E572; Wed, 18 Dec 2019 15:31:13 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.43.17.44]) by smtp.corp.redhat.com (Postfix) with SMTP id EAFE168894; Wed, 18 Dec 2019 15:31:11 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Wed, 18 Dec 2019 16:31:09 +0100 (CET) Date: Wed, 18 Dec 2019 16:31:07 +0100 From: Oleg Nesterov To: Andy Lutomirski , Borislav Petkov , Brian Gerst , Ingo Molnar , Peter Anvin Cc: linux-kernel@vger.kernel.org, x86@kernel.org Subject: Q: does force_iret() make any sense today? Message-ID: <20191218153107.GA3489@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I do not pretend I understand the arch/x86/entry/ code, but it seems that asm does all the necessary checks and the "extra" TIF_NOTIFY_RESUME simply has no effect except tracehook_notify_resume() will be called for no reason? Oleg.