From patchwork Mon Aug 6 15:54:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 10557353 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CDCEC13AC for ; Mon, 6 Aug 2018 15:54:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BE1FA29251 for ; Mon, 6 Aug 2018 15:54:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B2C4229683; Mon, 6 Aug 2018 15:54:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 62BE229251 for ; Mon, 6 Aug 2018 15:54:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732396AbeHFSEC (ORCPT ); Mon, 6 Aug 2018 14:04:02 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:35464 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728626AbeHFSEC (ORCPT ); Mon, 6 Aug 2018 14:04:02 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D99D5819700D; Mon, 6 Aug 2018 15:54:18 +0000 (UTC) Received: from shalem.localdomain.com (ovpn-116-70.ams2.redhat.com [10.36.116.70]) by smtp.corp.redhat.com (Postfix) with ESMTP id 26B54104948E; Mon, 6 Aug 2018 15:54:17 +0000 (UTC) From: Hans de Goede To: Bartlomiej Zolnierkiewicz Cc: Hans de Goede , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org Subject: [PATCH fix for 4.19] fbcon: Do not takeover the console from atomic context Date: Mon, 6 Aug 2018 17:54:16 +0200 Message-Id: <20180806155416.15752-1-hdegoede@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Mon, 06 Aug 2018 15:54:18 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Mon, 06 Aug 2018 15:54:18 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'hdegoede@redhat.com' RCPT:'' Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Taking over the console involves allocating mem with GFP_KERNEL, talking to drm drivers, etc. So this should not be done from an atomic context. But the console-output trigger deferred console takeover may happen from an atomic context, which leads to "BUG: sleeping function called from invalid context" errors. This commit fixes these errors by doing the deferred takeover from a workqueue when the notifier runs from an atomic context. Signed-off-by: Hans de Goede --- drivers/video/fbdev/core/fbcon.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index ef8b2d0b7071..4e5997d53fc4 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -3592,7 +3592,20 @@ static int fbcon_init_device(void) } #ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER +static void fbcon_register_existing_fbs(struct work_struct *work) +{ + int i; + + console_lock(); + + for_each_registered_fb(i) + fbcon_fb_registered(registered_fb[i]); + + console_unlock(); +} + static struct notifier_block fbcon_output_nb; +static DECLARE_WORK(fbcon_deferred_takeover_work, fbcon_register_existing_fbs); static int fbcon_output_notifier(struct notifier_block *nb, unsigned long action, void *data) @@ -3607,8 +3620,12 @@ static int fbcon_output_notifier(struct notifier_block *nb, deferred_takeover = false; logo_shown = FBCON_LOGO_DONTSHOW; - for_each_registered_fb(i) - fbcon_fb_registered(registered_fb[i]); + if (in_atomic() || irqs_disabled()) { + schedule_work(&fbcon_deferred_takeover_work); + } else { + for_each_registered_fb(i) + fbcon_fb_registered(registered_fb[i]); + } return NOTIFY_OK; }