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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 65EC3C10F12 for ; Mon, 15 Apr 2019 19:23:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 26D5B20651 for ; Mon, 15 Apr 2019 19:23:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555356185; bh=3pfRlHGvDOfiJHSPXsEvGAxacrekbSneK81BfCV8twg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0VlAxFpHcnmHs1qc/uVFa3GB8i6iace+vqRp7Ri7NvHrcx5UZcRJsVRUkrx4QFBEb /dANBVS/j/ccMOigXD8ZsRtfGOWW2E5/y8vCB8gzhmTmuzmuhvn3FRdqlx/OkoPYRY 6KX0Js+sZtWoqm3RLyqR01vQ3kTqacIpqcG+3Jj8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728200AbfDOTHy (ORCPT ); Mon, 15 Apr 2019 15:07:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:43054 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729806AbfDOTHy (ORCPT ); Mon, 15 Apr 2019 15:07:54 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4AF922087C; Mon, 15 Apr 2019 19:07:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555355273; bh=3pfRlHGvDOfiJHSPXsEvGAxacrekbSneK81BfCV8twg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h/koQAZbd+7+CRTMCEJnOcyYKqd1zCW4eyyNQCEoUYBqo+rpoZKpjAIFFM9uqdKdY AjYTocQrOdEcOLzw3NQcWa5F8hptG2YJzPmjEHtIBbuOXtEOs9mVlXh4gPZZ4hroYg eVf5ge2WHACmhJFiI5BEN1ICENnAvVNie06eYaos= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Helge Deller Subject: [PATCH 4.19 056/101] parisc: Detect QEMU earlier in boot process Date: Mon, 15 Apr 2019 20:58:54 +0200 Message-Id: <20190415183743.487943324@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190415183740.341577907@linuxfoundation.org> References: <20190415183740.341577907@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Helge Deller commit d006e95b5561f708d0385e9677ffe2c46f2ae345 upstream. While adding LASI support to QEMU, I noticed that the QEMU detection in the kernel happens much too late. For example, when a LASI chip is found by the kernel, it registers the LASI LED driver as well. But when we run on QEMU it makes sense to avoid spending unnecessary CPU cycles, so we need to access the running_on_QEMU flag earlier than before. This patch now makes the QEMU detection the fist task of the Linux kernel by moving it to where the kernel enters the C-coding. Fixes: 310d82784fb4 ("parisc: qemu idle sleep support") Signed-off-by: Helge Deller Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Greg Kroah-Hartman --- arch/parisc/kernel/process.c | 6 ------ arch/parisc/kernel/setup.c | 3 +++ 2 files changed, 3 insertions(+), 6 deletions(-) --- a/arch/parisc/kernel/process.c +++ b/arch/parisc/kernel/process.c @@ -210,12 +210,6 @@ void __cpuidle arch_cpu_idle(void) static int __init parisc_idle_init(void) { - const char *marker; - - /* check QEMU/SeaBIOS marker in PAGE0 */ - marker = (char *) &PAGE0->pad0; - running_on_qemu = (memcmp(marker, "SeaBIOS", 8) == 0); - if (!running_on_qemu) cpu_idle_poll_ctrl(1); --- a/arch/parisc/kernel/setup.c +++ b/arch/parisc/kernel/setup.c @@ -399,6 +399,9 @@ void __init start_parisc(void) int ret, cpunum; struct pdc_coproc_cfg coproc_cfg; + /* check QEMU/SeaBIOS marker in PAGE0 */ + running_on_qemu = (memcmp(&PAGE0->pad0, "SeaBIOS", 8) == 0); + cpunum = smp_processor_id(); init_cpu_topology();