From patchwork Mon May 19 07:10:13 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Zimmermann X-Patchwork-Id: 891170 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0634F265CD8 for ; Mon, 19 May 2025 07:13:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=195.135.223.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747638835; cv=none; b=iWRphAO9PwBt13dNPKtrOdkQydJZlKK+XnaSir+nVMiwL0AEg33CgBuRZ118GoxlhAcK3VdukezPI6yWWnd5Sd/2nS+/Q1iA4BL8tQYqZRtm4jdWo2Wm7elJo9ACVyL2goRvoPr4z1Y50F0WYKFTpY9xIDguqpZoGeBtcTqnrRE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747638835; c=relaxed/simple; bh=02WXJ2e8nA1m8WxpiEMjKR6s0y9GjQ3QRKT5VE7jbsI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=uyN8dnb7z6D706RN0VxbCp5VpPBAarzdsZ0KcNEKtX4/RekcczjOYxbx2KHCqgrC6/a+LniolZNLt7mDAUbLviYyfv3w43L98KRn1TobBNsMHG2i96cvf37nNb2Tfsz5rFV/ikzChxQVoFhzjLWs3Ya9t1/Elw7cNJ2dttNs+Pg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=suse.de; spf=pass smtp.mailfrom=suse.de; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b=nkLRKO5V; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b=gK/kmJUq; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b=nkLRKO5V; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b=gK/kmJUq; arc=none smtp.client-ip=195.135.223.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b="nkLRKO5V"; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b="gK/kmJUq"; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b="nkLRKO5V"; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b="gK/kmJUq" Received: from imap1.dmz-prg2.suse.org (imap1.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 16D86201F5; Mon, 19 May 2025 07:13:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1747638830; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=41Ev+vXHsAlb6sUce4V4iL7xMCren5QpN4AM1XVCMxQ=; b=nkLRKO5VAA8+WH5Oo51570Xz7riWN8ZERdTzGvyBnFnQErP33CEkV3BuBnlgIhO9M9teT8 IRaTE3qU1mo5BVTDLi968m/kK2bQRinqrm13/2nvgAFA6LAcHJRzHnsNI0r0t8HhkedSPT rVY9jxg6pgTuOGiGn2pU59faW81j6U4= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1747638830; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=41Ev+vXHsAlb6sUce4V4iL7xMCren5QpN4AM1XVCMxQ=; b=gK/kmJUqkyEwAqVD4dr+GHzwN4khEuv6j3JUBy28P0kJeYqT/jJmdNdJKkODgfGXzT+V+B HVsvLWBtfGrH6RCQ== Authentication-Results: smtp-out2.suse.de; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=nkLRKO5V; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b="gK/kmJUq" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1747638830; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=41Ev+vXHsAlb6sUce4V4iL7xMCren5QpN4AM1XVCMxQ=; b=nkLRKO5VAA8+WH5Oo51570Xz7riWN8ZERdTzGvyBnFnQErP33CEkV3BuBnlgIhO9M9teT8 IRaTE3qU1mo5BVTDLi968m/kK2bQRinqrm13/2nvgAFA6LAcHJRzHnsNI0r0t8HhkedSPT rVY9jxg6pgTuOGiGn2pU59faW81j6U4= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1747638830; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=41Ev+vXHsAlb6sUce4V4iL7xMCren5QpN4AM1XVCMxQ=; b=gK/kmJUqkyEwAqVD4dr+GHzwN4khEuv6j3JUBy28P0kJeYqT/jJmdNdJKkODgfGXzT+V+B HVsvLWBtfGrH6RCQ== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id CCD061372E; Mon, 19 May 2025 07:13:49 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id 74HgLy3aKmgzTgAAD6G6ig (envelope-from ); Mon, 19 May 2025 07:13:49 +0000 From: Thomas Zimmermann To: gregkh@linuxfoundation.org, hdegoede@redhat.com, arvidjaar@gmail.com Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Zimmermann , stable@vger.kernel.org Subject: [PATCH] dummycon: Trigger redraw when switching consoles with deferred takeover Date: Mon, 19 May 2025 09:10:13 +0200 Message-ID: <20250519071026.11133-1-tzimmermann@suse.de> X-Mailer: git-send-email 2.49.0 Precedence: bulk X-Mailing-List: linux-fbdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Rspamd-Action: no action X-Spam-Level: X-Rspamd-Queue-Id: 16D86201F5 X-Spam-Score: -2.01 X-Spam-Flag: NO X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-2.01 / 50.00]; DWL_DNSWL_MED(-2.00)[suse.de:dkim]; NEURAL_HAM_LONG(-1.00)[-1.000]; MID_CONTAINS_FROM(1.00)[]; R_MISSING_CHARSET(0.50)[]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; TO_DN_SOME(0.00)[]; ARC_NA(0.00)[]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; MIME_TRACE(0.00)[0:+]; FUZZY_BLOCKED(0.00)[rspamd.com]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FREEMAIL_TO(0.00)[linuxfoundation.org,redhat.com,gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_TLS_ALL(0.00)[]; DKIM_TRACE(0.00)[suse.de:+]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo,suse.com:url,suse.de:email,suse.de:mid,suse.de:dkim]; RCPT_COUNT_SEVEN(0.00)[8]; DNSWL_BLOCKED(0.00)[2a07:de40:b281:106:10:150:64:167:received,2a07:de40:b281:104:10:150:64:97:from]; RCVD_VIA_SMTP_AUTH(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; FREEMAIL_ENVRCPT(0.00)[gmail.com] Signal vt subsystem to redraw console when switching to dummycon with deferred takeover enabled. Makes the console switch to fbcon and displays the available output. With deferred takeover enabled, dummycon acts as the placeholder until the first output to the console happens. At that point, fbcon takes over. If the output happens while dummycon is not active, it cannot inform fbcon. This is the case if the vt subsystem runs in graphics mode. A typical graphical boot starts plymouth, a display manager and a compositor; all while leaving out dummycon. Switching to a text-mode console leaves the console with dummycon even if a getty terminal has been started. Returning true from dummycon's con_switch helper signals the vt subsystem to redraw the screen. If there's output available dummycon's con_putc{s} helpers trigger deferred takeover of fbcon, which sets a display mode and displays the output. If no output is available, dummycon remains active. Signed-off-by: Thomas Zimmermann Reported-by: Andrei Borzenkov Closes: https://bugzilla.suse.com/show_bug.cgi?id=1242191 Tested-by: Andrei Borzenkov Fixes: 83d83bebf401 ("console/fbcon: Add support for deferred console takeover") Cc: Hans de Goede Cc: linux-fbdev@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Cc: # v4.19+ Acked-by: Javier Martinez Canillas --- drivers/video/console/dummycon.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c index 139049368fdc..afb8e4d2fc34 100644 --- a/drivers/video/console/dummycon.c +++ b/drivers/video/console/dummycon.c @@ -85,6 +85,12 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank, /* Redraw, so that we get putc(s) for output done while blanked */ return true; } + +static bool dummycon_switch(struct vc_data *vc) +{ + /* Redraw, so that we get putc(s) for output done while switched away */ + return true; +} #else static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y, unsigned int x) { } @@ -95,6 +101,10 @@ static bool dummycon_blank(struct vc_data *vc, enum vesa_blank_mode blank, { return false; } +static bool dummycon_switch(struct vc_data *vc) +{ + return false; +} #endif static const char *dummycon_startup(void) @@ -124,11 +134,6 @@ static bool dummycon_scroll(struct vc_data *vc, unsigned int top, return false; } -static bool dummycon_switch(struct vc_data *vc) -{ - return false; -} - /* * The console `switch' structure for the dummy console *