Bug 577360

Summary:	x11-drivers/xf86-video-vesa: add kernelcheck for xf86-video-vesa
Product:	Gentoo Linux	Reporter:	jan vereecke <vereecke.jan>
Component:	[OLD] Unspecified	Assignee:	Matt Turner <mattst88>
Status:	RESOLVED FIXED
Severity:	normal	CC:	x11
Priority:	Normal
Version:	unspecified
Hardware:	x86
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---

Description jan vereecke 2016-03-14 09:51:09 UTC

I tried the xf86-video-vesa driver with xorg-server-1.18.1 and xorg-server-1.17.4, and got in both cases an error in Xorg.0.log:
Cannot read int vect
Cannot read BIOS
Cannot load vbe

By downgrading to xorg-server-1.16 I finally got a meaningfull error:
(WW) xf86ReadBIOS: Failed to open /dev/mem (No such file or directory)
(this bios call has been changed after 16.x, and the error message became less specific).

Based on this error message I found out I needed to set CONFIG_DEVMEM in the kernel in order to get the vesa driver running. 
Given that it is not possible anymore to read the root cause from the Xorg log, I  suggest to add a kernel check to the vesa driver and verify if the kernel option mentioned above is active.

Comment 1 Matt Turner gentoo-dev

2017-01-29 07:06:15 UTC

Good idea. Fixed by:

commit aafa644775d31150722aef2a6a68925a016aaa72
Author: Matt Turner <mattst88@gentoo.org>
Date:   Sat Jan 28 23:03:50 2017 -0800

    x11-drivers/xf86-video-vesa: Check for CONFIG_DEVMEM.