From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=60.234.4.34 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794475426; b=e2gfBITquUttg9L8fgQsZKCfPjSIQGSAQTEErbLew0yBcHuKsh6QyvL1kjGGeTzxdVbi 1+PkCZzgzjtr6/sqU9mrw2GMnVyqwaT120+2CZriWgwG3My66va0NzBabf6WVcD6X0+p4 6kGkZTnlwVTFZrH8tHW6yFw6EEI3asafV9Etc59PgJOXiVlouZ/0TV96FAlIEwZm8KaG4 vklA5u5Xe1yruEDw4CVnFJeI7vLuYQriuq7bX9aojLAqBZjy2gPkUDYEvLUvwc5s3L5xT w93E+e77jIV3kjn46LKisE6/rBt1jxevXU0xSt0RPvx+vDFTM3nHrC5Eoic6Nd21J9w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794475426; h=DMARC-Filter:DKIM-Signature:Received:Date:From:To:Cc:Subject: Message-ID:Mail-Followup-To:References:MIME-Version:Content-Type: Content-Disposition:Content-Transfer-Encoding:In-Reply-To:X-GeoIP: X-Spam_score:X-Spam_score_int:X-Spam_bar; bh=wvP1IpdD/AteWXcjJU0nzeoI5hxjbUtZch5zGuNerP8=; b=TLN7s0la5hfZ7pmAO4+GeRjmlx+T4E38BG42lJcJpvs3kYRUsQPkYqilUn9qKBFHzRQ6 BbI9BfmEJQS7uKoPy7JbSDEuIUNvwNbI7WBEEQiDUBuxX+ZUwqHOIMuM3kO9D880sRLyO 844naogEyq4vhcgqW+NPLMTgLSpr05QVihaN20T5rRSoMdTRy7F7jrI2IGumGyt9I6PMb hI4WX3uhIRgbFrz9QuDU/Sw6ZpjIOhh+PgFVq9Zvu1jWk1t09t7luxnlITVczvoF4k/d9 rI+F9rH3duF9gzKwj8pI0cUt6kB+jOAzCNP5ahC6J3auwmiYpHBw2eeAKcxwCW1FTTA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=orcon.net.nz; spf=pass smtp.mailfrom=orcon.net.nz; dkim=pass header.d=orcon.net.nz header.i=@orcon.net.nz header.a=rsa-sha256 header.s=s1 header.b="H+Ntv/v9"; arc=none smtp.remote-ip=60.234.4.34 Received: from smtp-1.orcon.net.nz (smtp-1.orcon.net.nz [60.234.4.34]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D8FC606A32E; Thu, 12 Nov 2026 09:23:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 3D8FC606A32E Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=orcon.net.nz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=orcon.net.nz Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=orcon.net.nz header.i=@orcon.net.nz header.a=rsa-sha256 header.s=s1 header.b=H+Ntv/v9 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=orcon.net.nz; s=s1; h=In-Reply-To:Content-Transfer-Encoding:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=wvP1IpdD/AteWXcjJU0nzeoI5hxjbUtZch5zGuNerP8=; b=H+Ntv/v9QVBOsz9oTSYZMoX+9M JvGFe0NQdExOREjXfWYswUeXGdmMeK6KLw0nStVcHCePJiOUNQRKLHDk8M8BOUt2N+YaYuMNnsbwL Npzx7m5G6iH+aY18SCsbKKqYg2T0uTksVBQJ67mp9hTI6BKuI0OS+5QoZhkrnUxV+GNrtXBDM39S/ AXbKDAqbF3hr/oqjemzKG6Qzslw6r26cbF+v7IIiOxvEogwl2s7oBu7tFHlsDsVdxv5chCkiSo1xO kvuIqZgLc+AIqlIUNZ7N9EQdglMec6xtIJFvaKxeNi49M+6cYpeGiyuSVz0GAak9+WeabAbHM0o/x VdZPGsQw==; Received: from [121.99.247.178] (port=59701 helo=creeky) by smtp-1.orcon.net.nz with esmtpa (Exim 4.90_1) (envelope-from ) id 1xRR1q-00019G-MK; Thu, 12 Nov 2026 22:23:34 +1300 Date: Thu, 12 Nov 2026 22:23:33 +1300 From: Michael Cree To: Magnus Lindholm Cc: Matt Turner , Greg Kroah-Hartman , Helge Deller , linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] vgacon: Fall back to the dummy console if mapping VGA memory fails Message-ID: Mail-Followup-To: Michael Cree , Magnus Lindholm , Matt Turner , Greg Kroah-Hartman , Helge Deller , linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, stable@vger.kernel.org References: <20261111-vgacon-ioremap-null-v1-1-6dd05bf390ef@gmail.com> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-GeoIP: NZ X-Spam_score: -2.9 X-Spam_score_int: -28 X-Spam_bar: -- On Thu, Nov 12, 2026 at 09:47:05AM +0100, Magnus Lindholm wrote: > Hi Matt, > > On Thu, Nov 12, 2026 at 1:30 AM Matt Turner wrote: > > > > On Alpha, setup_arch() registers vgacon whenever CONFIG_VGA_CONSOLE is > > enabled. On Marvel (EV7) systems whose SRM console is serial, no VGA > > hose is set, so marvel_ioremap() finds no hose for 0xb8000 and returns > > NULL. vgacon_startup() then probes video memory through that NULL > > pointer and oopses in console_init(): > > > > Unable to handle kernel paging request at virtual address 0000000000000000 > > pc is at vgacon_startup+0x174/0x910 > > > > VGA_MAP_MEM() is ioremap() on Alpha and powerpc and can fail. Treat > > failure like a failed probe and fall back to the dummy console. If a > > VGA card is present, locate_and_init_vga() still switches to vgacon > > once PCI is up. > > > > Cc: stable@vger.kernel.org > > Assisted-by: Claude:claude-opus-5-5 > > Signed-off-by: Matt Turner > > --- > > drivers/video/console/vgacon.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c > > index e7e6750f1f87..09f7c376b468 100644 > > --- a/drivers/video/console/vgacon.c > > +++ b/drivers/video/console/vgacon.c > > @@ -324,6 +324,8 @@ static const char *vgacon_startup(void) > > } > > > > vga_vram_base = VGA_MAP_MEM(vga_vram_base, vga_vram_size); > > + if (!vga_vram_base) > > + goto no_vga; > > vga_vram_end = vga_vram_base + vga_vram_size; > > > > /* > > > > --- > > base-commit: fa4ad798f6f681031775266044ba1b0cf3c670bd > > change-id: 20261111-vgacon-ioremap-null-ad4c7184b807 > > > > Best regards, > > -- > > Matt Turner > > > > > > Nice fix! this must have been lingering here for a long time? > Cross-builds passed for generic Alpha, including Marvel. The shared > vgacon code also compiled successfully for x86-64. I wonder whether this is the reason why my ES45 would never boot with an AGP video card. SRM could bring up the console but I recall the kernel crashed early on. In contrast, it boots fine with a PCI radeon card. Not sure if I am going to get a chance to test it out in the near future though ... Cheers, Michael.