From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 646241CAA92 for ; Mon, 13 Oct 2025 20:48:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760388530; cv=none; b=MiyHe+RlzomlOhUX3vfVdaHQFB6Bczsgw5rWrkU4EGC/IWeP9ayXrYDfZdGqfzsSS8wmilZY2zPW72hUlcP3aUmFOYwpSKjO0jGfOCwDa0LcoEYYonLA8906EWJ4sbddxxaF2ktcn/KBFX2sN9ydWEass9JbAljb8nMjkhAXTzc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760388530; c=relaxed/simple; bh=pyDPp24I/7VnQHW/ZQI+4Jc0hftTq8BmO+KF8SAV8So=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=API8miOZDA/dqmexfSBLSg96ZavMj7GurhZHGsbBzx7yWGx6xl5pXbY2YTPaMbjyyJzwfcqnl3k8HjtO1HabMrQsRSAfYZn/xnlsfAi6RfXVYpMq9KhObjkmEHR+VwF/NdpDaotnX6LqsG3aSOqSzlCuKoRCkABs+sWnyubdbyM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eZBuPTvl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eZBuPTvl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E995C4CEE7; Mon, 13 Oct 2025 20:48:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760388529; bh=pyDPp24I/7VnQHW/ZQI+4Jc0hftTq8BmO+KF8SAV8So=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=eZBuPTvl7YK4vTzMT/FOV4DzPCgnGAazEQO31/oop7F6AJnDtk751tIXunUVBPN/u 0Eoxd33JeK5nRYvYyz7HtAhS/h0GeQrl1rTo9EAQH63K/p17zVbb61nEA6V7tv09CP qdky9xyxdvO2KusAXjqJ/QsZdK5h9ybhI7ENU+jw74hEZDxUsTn7FIjUxGW9yFK+9T fvBUh0NekZXxsIZPgczjbWTTLobItormEzzdyAYpGVSwJmDYCUD/EAXqpEx/VPacAf dWk/9UKQjQbC+BA6F22Be2wRlylfV4tIRpSIwToLQqMkSbhnmOYvc2pY97yVyxTCvl E/u+nNsaSL5Gg== Message-ID: <6bb7a607-174d-4914-9452-fe0e36be9e2e@kernel.org> Date: Mon, 13 Oct 2025 15:48:48 -0500 Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] PCI/VGA: Select SCREEN_INFO To: Bjorn Helgaas Cc: mario.limonciello@amd.com, bhelgaas@google.com, tzimmermann@suse.de, Eric Biggers , linux-pci@vger.kernel.org References: <20251013204738.GA863114@bhelgaas> Content-Language: en-US From: Mario Limonciello In-Reply-To: <20251013204738.GA863114@bhelgaas> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/13/25 3:47 PM, Bjorn Helgaas wrote: > On Mon, Oct 13, 2025 at 12:55:25PM -0500, Bjorn Helgaas wrote: >> On Mon, Oct 13, 2025 at 10:44:23AM -0500, Mario Limonciello (AMD) wrote: >>> commit 337bf13aa9dda ("PCI/VGA: Replace vga_is_firmware_default() with >>> a screen info check") introduced an implicit dependency upon SCREEN_INFO >>> by removing the open coded implementation. >>> >>> If a user didn't have CONFIG_SCREEN_INFO set vga_is_firmware_default() >>> would now return false. Add a select for SCREEN_INFO to ensure that the >>> VGA arbiter works as intended. Also drop the now dead code. >>> >>> Reported-by: Eric Biggers >>> Closes: https://lore.kernel.org/linux-pci/20251012182302.GA3412@sol/ >>> Suggested-by: Thomas Zimmermann >>> Fixes: 337bf13aa9dda ("PCI/VGA: Replace vga_is_firmware_default() with a screen info check") >>> Signed-off-by: Mario Limonciello (AMD) >> >> Applied to for-linus for v6.18, thanks! > > Oops, dropped because of this regression: > > https://lore.kernel.org/r/176038554347.1442.9483731885505420131@15dd6324cc71 Ah thanks for that. I hadn't had non-x86 to test. I'll try to cross compile to repro and come up with a solution. > >>> --- >>> v2: >>> * drop dead code (Ilpo) >>> --- >>> drivers/pci/Kconfig | 1 + >>> drivers/pci/vgaarb.c | 8 +------- >>> 2 files changed, 2 insertions(+), 7 deletions(-) >>> >>> diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig >>> index 7065a8e5f9b14..c35fed47addd5 100644 >>> --- a/drivers/pci/Kconfig >>> +++ b/drivers/pci/Kconfig >>> @@ -306,6 +306,7 @@ config VGA_ARB >>> bool "VGA Arbitration" if EXPERT >>> default y >>> depends on (PCI && !S390) >>> + select SCREEN_INFO >>> help >>> Some "legacy" VGA devices implemented on PCI typically have the same >>> hard-decoded addresses as they did on ISA. When multiple PCI devices >>> diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c >>> index b58f94ee48916..8c8c420ff5b55 100644 >>> --- a/drivers/pci/vgaarb.c >>> +++ b/drivers/pci/vgaarb.c >>> @@ -556,13 +556,7 @@ EXPORT_SYMBOL(vga_put); >>> >>> static bool vga_is_firmware_default(struct pci_dev *pdev) >>> { >>> -#ifdef CONFIG_SCREEN_INFO >>> - struct screen_info *si = &screen_info; >>> - >>> - return pdev == screen_info_pci_dev(si); >>> -#else >>> - return false; >>> -#endif >>> + return pdev == screen_info_pci_dev(&screen_info); >>> } >>> >>> static bool vga_arb_integrated_gpu(struct device *dev) >>> -- >>> 2.43.0 >>>