Commit a78835b8 authored by Mario Limonciello (AMD)'s avatar Mario Limonciello (AMD) Committed by Bjorn Helgaas
Browse files

PCI/VGA: Select SCREEN_INFO on X86 



commit 337bf13a ("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.  SCREEN_INFO is only used on X86 so add a
conditional select for SCREEN_INFO to ensure that the VGA arbiter works as
intended.

Fixes: 337bf13a ("PCI/VGA: Replace vga_is_firmware_default() with a screen info check")
Reported-by: default avatarEric Biggers <ebiggers@kernel.org>
Closes: https://lore.kernel.org/linux-pci/20251012182302.GA3412@sol/


Suggested-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: default avatarMario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: default avatarEric Biggers <ebiggers@kernel.org>
Link: https://patch.msgid.link/20251013220829.1536292-1-superm1@kernel.org
parent e433110e

drivers/pci/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -306,6 +306,7 @@ config VGA_ARB 
	bool "VGA Arbitration" if EXPERT

	default y

	depends on (PCI && !S390)

	select SCREEN_INFO if X86

	help

	  Some "legacy" VGA devices implemented on PCI typically have the same

	  hard-decoded addresses as they did on ISA. When multiple PCI devices

drivers/pci/vgaarb.c

+2 −4
Original line number Diff line number Diff line
@@ -556,10 +556,8 @@ 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);

#if defined CONFIG_X86

	return pdev == screen_info_pci_dev(&screen_info);

#else

	return false;

#endif