From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bruno =?UTF-8?B?UHLDqW1vbnQ=?= Date: Fri, 14 Nov 2014 14:42:52 +0000 Subject: Re: [PATCH] x86, ia64: Do not lose track of the EFI default VGA device Message-Id: <20141114154252.0fb66bba@pluto.restena.lu> List-Id: References: <1415969610-1469-1-git-send-email-rydberg@euromail.se> In-Reply-To: <1415969610-1469-1-git-send-email-rydberg@euromail.se> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: Henrik Rydberg Cc: Peter Jones , Jean-Christophe Plagniol-Villard , Tomi Valkeinen , Bjorn Helgaas , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org On Fri, 14 Nov 2014 13:53:30 +0100 Henrik Rydberg wrote: > Since commit 20cde694027e ("x86, ia64: Move EFI_FB > vga_default_device() initialization to pci_vga_fixup()") 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. Could you be more verbose in why it depends on/needs VGA_ARB? With EFI starting to show up on ARM this is not necessarily true (no PCI -> no VGA_ARB arbitration). 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. Bruno > Cc: Bruno Pr=C3=A9mont > Signed-off-by: Henrik Rydberg > --- > Hi Peter, >=20 > I stumbled upon this bug from the 3.17 merge window when updating to > Linus's 3.18 git head yesterday. The patch has been tested on two > different EFI machines; one that needs the patch and one that does not. >=20 > Thanks, > Henrik >=20 > drivers/video/fbdev/Kconfig | 1 + > 1 file changed, 1 insertion(+) >=20 > diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig > index c7bf606..81b21bc 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 > 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