From patchwork Tue May 21 14:23:04 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 10953909 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 2F8761395 for ; Tue, 21 May 2019 14:23:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1DEB428941 for ; Tue, 21 May 2019 14:23:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0AA40289CC; Tue, 21 May 2019 14:23:20 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 7433C28941 for ; Tue, 21 May 2019 14:23:19 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1D93A893D0; Tue, 21 May 2019 14:23:16 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-ed1-x541.google.com (mail-ed1-x541.google.com [IPv6:2a00:1450:4864:20::541]) by gabe.freedesktop.org (Postfix) with ESMTPS id ACFFB893D0 for ; Tue, 21 May 2019 14:23:14 +0000 (UTC) Received: by mail-ed1-x541.google.com with SMTP id j12so29678248eds.7 for ; Tue, 21 May 2019 07:23:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=3gXOlvlwJpwesLdU0wAdD0yVcQscPI1RKWlQt+svte8=; b=P9SpVF1fnP1vKIwL8G3g64KDkBQc68TbOEaHTXUolH8PpKv2N3kAcVB6XjPd9AQypK rKuOd5NT/yo4g9e4RE34SAlfHr9t8OJmX9Nky44T8hXhNR6OdD9B9U9msqmIfJG4mxyx iAka5Vk/l5QHBfNNLEf2/FZUfwlrVVHDYaQ5+OCz1kmwxOeaAtpItvttG6UUTcnPo7cU j2SKELc84NyO8SLvxSA9DYtuy/affRy4Fj6g3vD/3Fj2sR/3DAdnshjzsEEGOj+mJlxp VE/g+6Ia6Z7cwVtTNIHYGI865q/wq8jpzdcJ0ZhnkrSDgShY+hD2CuMdkEzZtRDRl565 fe0w== X-Gm-Message-State: APjAAAVCfy/OEvz/Jjqa/GQYhUfNub/g0Pb+imkhsTzLzNmASYOgiGyU aZDxIkPfPVgoSUr/gfoGb1LreTVbP2s= X-Google-Smtp-Source: APXvYqy9ymxY3fIje99hwSr24R9iys+xHdJialvsImhQdV7ko64jootOFxP+Uar5GiWIF402KYBrrA== X-Received: by 2002:a17:906:1fc4:: with SMTP id e4mr45550864ejt.81.1558448593084; Tue, 21 May 2019 07:23:13 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:569e:0:3106:d637:d723:e855]) by smtp.gmail.com with ESMTPSA id c49sm6427547eda.58.2019.05.21.07.23.11 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 21 May 2019 07:23:12 -0700 (PDT) From: Daniel Vetter To: DRI Development Subject: [PATCH] fbcon: Remove fbcon_has_exited Date: Tue, 21 May 2019 16:23:04 +0200 Message-Id: <20190521142304.9652-1-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190520082216.26273-10-daniel.vetter@ffwll.ch> References: <20190520082216.26273-10-daniel.vetter@ffwll.ch> MIME-Version: 1.0 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=3gXOlvlwJpwesLdU0wAdD0yVcQscPI1RKWlQt+svte8=; b=g6Zkc/dMLE5Boejgu8PEXQ+7QOwTTqousEgB/e+KN9uezhGHXV4C7M3mwALTnyUsVZ 3oN70CAVtJZbn6iyWpezw0DBjDdx5iG04Kbd96QFMHc7FVeCzeE+AqNTcSstgrbvlNCk NyjYUe9P03iNTR8Inhi/rQAa5seslO2wnmMIU= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Prarit Bhargava , Kees Cook , Bartlomiej Zolnierkiewicz , Daniel Vetter , Intel Graphics Development , LKML , Yisheng Xie , Hans de Goede , Daniel Vetter , Konstantin Khorenko Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP This is unused code since commit 6104c37094e729f3d4ce65797002112735d49cd1 Author: Daniel Vetter Date: Tue Aug 1 17:32:07 2017 +0200 fbcon: Make fbcon a built-time depency for fbdev when fbcon was made a compile-time static dependency of fbdev. We can't exit fbcon anymore without exiting fbdev first, which only works if all fbdev drivers have unloaded already. Hence this is all dead code. v2: I missed that fbcon_exit is also called from con_deinit stuff, and there fbcon_has_exited prevents double-cleanup. But we can fix that by properly resetting con2fb_map[] to all -1, which is used everywhere else to indicate "no fb_info allocate to this console". With that change the double-cleanup (which resulted in a module refcount underflow, among other things) is prevented. Aside: con2fb_map is a signed char, so don't register more than 128 fb_info or hilarity will ensue. v3: CI showed me that I still didn't fully understand what's going on here. The leaked references in con2fb_map have been used upon rebinding the fb console in fbcon_init. It worked because fbdev unregistering still cleaned out con2fb_map, and reset it to info_idx. If the last fbdev driver unregistered, then it also reset info_idx, and unregistered the fbcon driver. Imo that's all a bit fragile, so let's keep the con2fb_map reset to -1, and in fbcon_init pick info_idx if we're starting fresh. That means unbinding and rebinding will cleanse the mapping, but why are you doing that if you want to retain the mapping, so should be fine. Also, I think info_idx == -1 is impossible in fbcon_init - we unregister the fbcon in that case. So catch&warn about that. Signed-off-by: Daniel Vetter Cc: Maarten Lankhorst Cc: Bartlomiej Zolnierkiewicz Cc: Daniel Vetter Cc: Hans de Goede Cc: "Noralf Trønnes" Cc: Yisheng Xie Cc: Konstantin Khorenko Cc: Prarit Bhargava Cc: Kees Cook --- drivers/video/fbdev/core/fbcon.c | 39 +++++--------------------------- 1 file changed, 6 insertions(+), 33 deletions(-) diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index 5424051c8e1a..622d336cfc81 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -112,7 +112,6 @@ static int softback_lines; static int first_fb_vc; static int last_fb_vc = MAX_NR_CONSOLES - 1; static int fbcon_is_default = 1; -static int fbcon_has_exited; static int primary_device = -1; static int fbcon_has_console_bind; @@ -1050,7 +1049,6 @@ static const char *fbcon_startup(void) info->var.bits_per_pixel); fbcon_add_cursor_timer(info); - fbcon_has_exited = 0; return display_desc; } @@ -1064,9 +1062,13 @@ static void fbcon_init(struct vc_data *vc, int init) int logo = 1, new_rows, new_cols, rows, cols, charcnt = 256; int cap, ret; - if (info_idx == -1 || info == NULL) + if (WARN_ON(info_idx == -1)) return; + if (con2fb_map[vc->vc_num] == -1) + con2fb_map[vc->vc_num] = info_idx; + + info = registered_fb[con2fb_map[vc->vc_num]]; cap = info->flags; if (logo_shown < 0 && console_loglevel <= CONSOLE_LOGLEVEL_QUIET) @@ -3336,14 +3338,6 @@ static int fbcon_event_notify(struct notifier_block *self, struct fb_blit_caps *caps; int idx, ret = 0; - /* - * ignore all events except driver registration and deregistration - * if fbcon is not active - */ - if (fbcon_has_exited && !(action == FB_EVENT_FB_REGISTERED || - action == FB_EVENT_FB_UNREGISTERED)) - goto done; - switch(action) { case FB_EVENT_SUSPEND: fbcon_suspended(info); @@ -3396,7 +3390,6 @@ static int fbcon_event_notify(struct notifier_block *self, fbcon_remap_all(idx); break; } -done: return ret; } @@ -3443,9 +3436,6 @@ static ssize_t store_rotate(struct device *device, int rotate, idx; char **last = NULL; - if (fbcon_has_exited) - return count; - console_lock(); idx = con2fb_map[fg_console]; @@ -3468,9 +3458,6 @@ static ssize_t store_rotate_all(struct device *device, int rotate, idx; char **last = NULL; - if (fbcon_has_exited) - return count; - console_lock(); idx = con2fb_map[fg_console]; @@ -3491,9 +3478,6 @@ static ssize_t show_rotate(struct device *device, struct fb_info *info; int rotate = 0, idx; - if (fbcon_has_exited) - return 0; - console_lock(); idx = con2fb_map[fg_console]; @@ -3514,9 +3498,6 @@ static ssize_t show_cursor_blink(struct device *device, struct fbcon_ops *ops; int idx, blink = -1; - if (fbcon_has_exited) - return 0; - console_lock(); idx = con2fb_map[fg_console]; @@ -3543,9 +3524,6 @@ static ssize_t store_cursor_blink(struct device *device, int blink, idx; char **last = NULL; - if (fbcon_has_exited) - return count; - console_lock(); idx = con2fb_map[fg_console]; @@ -3668,9 +3646,6 @@ static void fbcon_exit(void) struct fb_info *info; int i, j, mapped; - if (fbcon_has_exited) - return; - #ifdef CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER if (deferred_takeover) { dummycon_unregister_output_notifier(&fbcon_output_nb); @@ -3695,7 +3670,7 @@ static void fbcon_exit(void) for (j = first_fb_vc; j <= last_fb_vc; j++) { if (con2fb_map[j] == i) { mapped = 1; - break; + con2fb_map[j] = -1; } } @@ -3718,8 +3693,6 @@ static void fbcon_exit(void) info->queue.func = NULL; } } - - fbcon_has_exited = 1; } void __init fb_console_init(void)