From patchwork Wed Jul 18 01:02:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Pitre X-Patchwork-Id: 142226 Delivered-To: patch@linaro.org Received: by 2002:a2e:9754:0:0:0:0:0 with SMTP id f20-v6csp219842ljj; Tue, 17 Jul 2018 18:02:53 -0700 (PDT) X-Google-Smtp-Source: AAOMgpfeRqQh3N/SBLqhiSyqHgT3Yg1ID0yMNoL7hHdk138zk7SfZ8AV+s8G0VVCEqLISg/Q5VrW X-Received: by 2002:a62:6d02:: with SMTP id i2-v6mr2932926pfc.218.1531875773671; Tue, 17 Jul 2018 18:02:53 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1531875773; cv=none; d=google.com; s=arc-20160816; b=avrNzZZ4oVw14SYEegUK+ibmO/3y5s/zvSYlh+r3WfjGii5t/FHcKAQshnRiFL0N9E V5xt8pfBzXCGVYCaZjG+u2hUfrFnn5OS29u3uvKRDUaFLnwQOL6VM7JCrCUMyrbCeOpG /CSKUZNCUINtJaWJL1S13mjeSH8ni8ThPYc7rDd76XZFdedmptcCfrsEKRd+tLRNOgaE AdL47Aph6gASxKmksx9ZzLVULzD80zKto15XEml/4rFvdbo2ZwnuabQuR/N+rQZqcXNL Z8pijQxHq7VufmaPaqzGccVNRw3DrBQWGWk42w1qrc9p4H3v+YjskDfOhI4AQfat75mQ 27pQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=nI5omes7ApS9ptVu/VgB1ARrYu6dA+yZLlNBuYaDtGA=; b=BcVw2nPhoiUtO+kjtuUb5H0ta37WNdbZwWhegXPYgDbmenQtN4nIgC4Rk6JxOUmG0K rSIHAgfJNYjEz6Brj6aSzk6QB4/tfzFascLqUG0W2FeQtN0KqSBVlVq9QcVw1wrRarVl yzAQ4QGcmclYUcYwaDahHlhsaV8WlMIdVqE/Xc6hxFIBEfmPMINwqy3B6eWItQMEF7dr neI/yad8V2R1mANyv9hR6UH828WZrGuj/bHNLxgGK1YILi/i2PHMbMDCdMl9+gsB4mZS 8F5p1ORvr/u8ofdoA2RQQgGpu8X3DBCpQSm0o3zvUhdKRh827qK3hjQFZEkfomm12aJy +VJw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@pobox.com header.s=sasl header.b=DETh6Rmj; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linaro.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id a18-v6si2205807pfc.106.2018.07.17.18.02.53; Tue, 17 Jul 2018 18:02:53 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@pobox.com header.s=sasl header.b=DETh6Rmj; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731659AbeGRBiE (ORCPT + 31 others); Tue, 17 Jul 2018 21:38:04 -0400 Received: from pb-smtp1.pobox.com ([64.147.108.70]:59416 "EHLO pb-smtp1.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731114AbeGRBiD (ORCPT ); Tue, 17 Jul 2018 21:38:03 -0400 Received: from pb-smtp1.pobox.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id EEB91EDF45; Tue, 17 Jul 2018 21:02:45 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:date:message-id:in-reply-to:references; s=sasl; bh=Z9a3 /MBdtj9jXUeSkq/yeCQ5zso=; b=DETh6RmjmbiGozGx70xavXS/vISp7hoKMcdN SSwgrzVOGCWo7CcZ5AWuKRsm2iJhxFx9v6fMgndBJB/ez/WFVXMQkxjiRrLKLgN0 aYPxt/w8MmjkxHZrv2uAthC8oSsILwzvJwzNd2Xtq0E4ow0oXgQ0myQ0veEf1xxV o/0aRKc= Received: from pb-smtp1.nyi.icgroup.com (unknown [127.0.0.1]) by pb-smtp1.pobox.com (Postfix) with ESMTP id DE65CEDF43; Tue, 17 Jul 2018 21:02:45 -0400 (EDT) Received: from yoda.home (unknown [70.82.104.228]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pb-smtp1.pobox.com (Postfix) with ESMTPSA id 46200EDF3C; Tue, 17 Jul 2018 21:02:45 -0400 (EDT) Received: from xanadu.home (xanadu.home [192.168.2.2]) by yoda.home (Postfix) with ESMTP id 6E7DE2DA0674; Tue, 17 Jul 2018 21:02:44 -0400 (EDT) From: Nicolas Pitre To: Greg Kroah-Hartman Cc: Kees Cook , Geert Uytterhoeven , Adam Borowski , Dave Mielke , Samuel Thibault , linux-kernel@vger.kernel.org, linux-console@vger.kernel.org Subject: [PATCH 2/3] vt: coherence validation code for the unicode screen buffer Date: Tue, 17 Jul 2018 21:02:41 -0400 Message-Id: <20180718010242.5254-3-nicolas.pitre@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180718010242.5254-1-nicolas.pitre@linaro.org> References: <20180718010242.5254-1-nicolas.pitre@linaro.org> X-Pobox-Relay-ID: 47D0A818-8A26-11E8-8E70-063AD72159A7-78420484!pb-smtp1.pobox.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Make sure the unicode screen buffer matches the video screen content. This is provided for debugging convenience and disabled by default. Signed-off-by: Nicolas Pitre --- drivers/tty/vt/vt.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) -- 2.17.1 diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 03e79f7787..331f175265 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -328,6 +328,8 @@ void schedule_console_callback(void) #define get_vc_uniscr(vc) vc->vc_uni_screen #endif +#define VC_UNI_SCREEN_DEBUG 0 + typedef uint32_t char32_t; /* @@ -571,6 +573,42 @@ void vc_uniscr_copy_line(struct vc_data *vc, void *dest, int viewed, } } +/* this is for validation and debugging only */ +static void vc_uniscr_debug_check(struct vc_data *vc) +{ + struct uni_screen *uniscr = get_vc_uniscr(vc); + unsigned short *p; + int x, y, mask; + + if (!VC_UNI_SCREEN_DEBUG || !uniscr) + return; + + WARN_CONSOLE_UNLOCKED(); + + /* + * Make sure our unicode screen translates into the same glyphs + * as the actual screen. This is brutal indeed. + */ + p = (unsigned short *)vc->vc_origin; + mask = vc->vc_hi_font_mask | 0xff; + for (y = 0; y < vc->vc_rows; y++) { + char32_t *line = uniscr->lines[y]; + for (x = 0; x < vc->vc_cols; x++) { + u16 glyph = scr_readw(p++) & mask; + char32_t uc = line[x]; + int tc = conv_uni_to_pc(vc, uc); + if (tc == -4) + tc = conv_uni_to_pc(vc, 0xfffd); + if (tc == -4) + tc = conv_uni_to_pc(vc, '?'); + if (tc != glyph) + pr_err_ratelimited( + "%s: mismatch at %d,%d: glyph=%#x tc=%#x\n", + __func__, x, y, glyph, tc); + } + } +} + static void con_scroll(struct vc_data *vc, unsigned int t, unsigned int b, enum con_scroll dir, unsigned int nr) @@ -2719,6 +2757,7 @@ static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int co do_con_trol(tty, vc, orig); } con_flush(vc, draw_from, draw_to, &draw_x); + vc_uniscr_debug_check(vc); console_conditional_schedule(); console_unlock(); notify_update(vc);