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=ham 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 0F164C43381 for ; Fri, 22 Mar 2019 12:09:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D394521929 for ; Fri, 22 Mar 2019 12:09:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553256570; bh=Dp9kn2dsroe4I/CEdu/K4i/iQCEw3KRyZMZgtPuI1YE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=c5b7ya0kIhICKUlUY8o413YSfy3ecU8oiHQ33NTzYDl/0e5n8E3F9siun3ejmGr/w 4m6Sumiq9yPytzhwI6biSfTm99QcdQwyUERtiv6guZdMpUy2+vaQBOug9SIkvPiNon pLu3TzILhChpJ9qaW77N4qhJIZC49uF2aCuqY7ow= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389324AbfCVMJ3 (ORCPT ); Fri, 22 Mar 2019 08:09:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:47912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389311AbfCVMJ0 (ORCPT ); Fri, 22 Mar 2019 08:09:26 -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 C9ACF2082C; Fri, 22 Mar 2019 12:09:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553256566; bh=Dp9kn2dsroe4I/CEdu/K4i/iQCEw3KRyZMZgtPuI1YE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LeXdZrw626NQOJPigVrDO51XT9VOBC7gJmMaDDVJvvros0ScxP1uO9+wVuL3RVdeF 25o+KXpZqmjbA+hwpvxr8Wxr8AZkbzH0h/Mwt8utfIz1Lojg6qNadI0RDc97ZMB9th pRmmgquRSRJLj7LIVJ/+xK/+8YZg7LI+nKoExHCk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Matthew Whitehead , Nicolas Pitre Subject: [PATCH 4.19 251/280] vt: perform safe console erase in the right order Date: Fri, 22 Mar 2019 12:16:44 +0100 Message-Id: <20190322111341.543743624@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111306.356185024@linuxfoundation.org> References: <20190322111306.356185024@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicolas Pitre commit a6dbe442755999960ca54a9b8ecfd9606be0ea75 upstream. Commit 4b4ecd9cb853 ("vt: Perform safe console erase only once") removed what appeared to be an extra call to scr_memsetw(). This missed the fact that set_origin() must be called before clearing the screen otherwise old screen content gets restored on the screen when using vgacon. Let's fix that by moving all the scrollback handling to flush_scrollback() where it logically belongs, and invoking it before the actual screen clearing in csi_J(), making the code simpler in the end. Reported-by: Matthew Whitehead Signed-off-by: Nicolas Pitre Tested-by: Matthew Whitehead Fixes: 4b4ecd9cb853 ("vt: Perform safe console erase only once") Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/tty/vt/vt.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -935,8 +935,11 @@ static void flush_scrollback(struct vc_d { WARN_CONSOLE_UNLOCKED(); + set_origin(vc); if (vc->vc_sw->con_flush_scrollback) vc->vc_sw->con_flush_scrollback(vc); + else + vc->vc_sw->con_switch(vc); } /* @@ -1506,8 +1509,10 @@ static void csi_J(struct vc_data *vc, in count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1; start = (unsigned short *)vc->vc_origin; break; + case 3: /* include scrollback */ + flush_scrollback(vc); + /* fallthrough */ case 2: /* erase whole display */ - case 3: /* (and scrollback buffer later) */ vc_uniscr_clear_lines(vc, 0, vc->vc_rows); count = vc->vc_cols * vc->vc_rows; start = (unsigned short *)vc->vc_origin; @@ -1516,13 +1521,7 @@ static void csi_J(struct vc_data *vc, in return; } scr_memsetw(start, vc->vc_video_erase_char, 2 * count); - if (vpar == 3) { - set_origin(vc); - flush_scrollback(vc); - if (con_is_visible(vc)) - update_screen(vc); - } else if (con_should_update(vc)) - do_update_region(vc, (unsigned long) start, count); + update_region(vc, (unsigned long) start, count); vc->vc_need_wrap = 0; }