Hi Bruno,

So it would need to at least be select VGA_ARB if (PCI && !S390)
in order to not have broken kernel configuration (in more or less
exotic cases) while depends on VGA_ARB would be the only correct option
if the rule 'select only allowed for leafs' is enforced.

Here is a tested patch that does just that, thanks for the suggestion.

Henrik

From 43c16bbc7adbcb17aac73d09f046bf2779771c4c Mon Sep 17 00:00:00 2001
From: Henrik Rydberg <redacted>
Date: Fri, 14 Nov 2014 20:01:21 +0100
Subject: [PATCH v2] x86, ia64: Do not lose track of the EFI default VGA device
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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Since commit 20cde694 in the 3.17 merge window, the EFI framebuffer
depends on the VGA arbitration layer. However, the configuration does
not reflect this, which leads to a hard-to-find bug when FB_EFI is
configured without VGA_ARB. Add a select clause to remedy this.

Cc: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Henrik Rydberg <redacted>
---
 drivers/video/fbdev/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index c7bf606..1615a1b 100644
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig

@@ -761,6 +761,7 @@ config FB_EFI
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT
+	select VGA_ARB if (PCI && !S390)
 	help
 	  This is the EFI frame buffer device driver. If the firmware on
 	  your platform is EFI 1.10 or UEFI 2.0, select Y to add support for

-- 
2.1.3