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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28836C77B75 for ; Tue, 23 May 2023 15:06:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237347AbjEWPGc (ORCPT ); Tue, 23 May 2023 11:06:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50994 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237135AbjEWPGb (ORCPT ); Tue, 23 May 2023 11:06:31 -0400 Received: from baptiste.telenet-ops.be (baptiste.telenet-ops.be [IPv6:2a02:1800:120:4::f00:13]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E23F5FA for ; Tue, 23 May 2023 08:06:26 -0700 (PDT) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed30:b0ac:7afd:272:4cff]) by baptiste.telenet-ops.be with bizsmtp id 0F6N2A0050Jkz7G01F6N0Z; Tue, 23 May 2023 17:06:24 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtp (Exim 4.95) (envelope-from ) id 1q1TaR-002svP-Hg; Tue, 23 May 2023 17:06:22 +0200 Received: from geert by rox.of.borg with local (Exim 4.95) (envelope-from ) id 1q1Taf-00CkGs-VW; Tue, 23 May 2023 17:06:21 +0200 From: Geert Uytterhoeven To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Javier Martinez Canillas Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven , Daniel Vetter , Sui Jingfeng Subject: [PATCH v2] drm/fb-helper: Fix height, width, and accel_flags in fb_var Date: Tue, 23 May 2023 17:06:20 +0200 Message-Id: <57e6b334dae8148b1b8ae6ef308ce9a83810a850.1684854344.git.geert+renesas@glider.be> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fbtest contains some very simple validation of the fbdev userspace API contract. When used with shmob-drm, it reports the following warnings and errors: height changed from 68 to 0 height was rounded down width changed from 111 to 0 width was rounded down accel_flags changed from 0 to 1 The first part happens because __fill_var() resets the physical dimensions of the first connector, as filled in by drm_setup_crtcs_fb(). Fix this by retaining the original values. The last part happens because __fill_var() forces the FB_ACCELF_TEXT flag on, while fbtest disables all acceleration on purpose, so it can draw safely to the frame buffer. Fix this by setting accel_flags to zero, as DRM does not implement any text console acceleration. Note that this issue can also be seen in the output of fbset, which reports "accel true". Fixes: ee4cce0a8f03a333 ("drm/fb-helper: fix input validation gaps in check_var") Signed-off-by: Geert Uytterhoeven Reviewed-by: Daniel Vetter Tested-by: Sui Jingfeng --- v2: - Add Reviewed-by, Tested-by. --- drivers/gpu/drm/drm_fb_helper.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index f0e9549b6bd751de..8dc376b771d2cf22 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1379,17 +1379,19 @@ static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var, } } -static void __fill_var(struct fb_var_screeninfo *var, +static void __fill_var(struct fb_var_screeninfo *var, struct fb_info *info, struct drm_framebuffer *fb) { int i; var->xres_virtual = fb->width; var->yres_virtual = fb->height; - var->accel_flags = FB_ACCELF_TEXT; + var->accel_flags = 0; var->bits_per_pixel = drm_format_info_bpp(fb->format, 0); - var->height = var->width = 0; + var->height = info->var.height; + var->width = info->var.width; + var->left_margin = var->right_margin = 0; var->upper_margin = var->lower_margin = 0; var->hsync_len = var->vsync_len = 0; @@ -1452,7 +1454,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, return -EINVAL; } - __fill_var(var, fb); + __fill_var(var, info, fb); /* * fb_pan_display() validates this, but fb_set_par() doesn't and just @@ -1908,7 +1910,7 @@ static void drm_fb_helper_fill_var(struct fb_info *info, info->pseudo_palette = fb_helper->pseudo_palette; info->var.xoffset = 0; info->var.yoffset = 0; - __fill_var(&info->var, fb); + __fill_var(&info->var, info, fb); info->var.activate = FB_ACTIVATE_NOW; drm_fb_helper_fill_pixel_fmt(&info->var, format); -- 2.34.1