[gentoo-amd64] Re: emerge -eav system failed with ati-drivers

[Duncan <1i5t5.duncan@cox.net>]

Nikos Chantziaras <realnc@arcor.de> posted h1jqlc$o63$1@ger.gmane.org,
excerpted below, on  Sun, 21 Jun 2009 02:17:02 +0300:

> zcat /proc/config.gz > .config

Note that /proc/config.gz depends on kernel config, so may not exist on 
all systems.  From the help text for "Kernel .config support" under 
"General setup" in menuconfig:

""""
CONFIG_IKCONFIG:                                                      

This option enables the complete Linux kernel ".config" file contents to 
be saved in the kernel. It provides documentation of which kernel options 
are used in a running kernel or in an on-disk kernel.  This information 
can be extracted from the kernel image file with the script scripts/
extract-ikconfig and used as input to rebuild the current kernel or to 
build another kernel. It can also be extracted from a running kernel by 
reading /proc/config.gz if enabled (below).     
""""

Then the dependent suboption:

""""
CONFIG_IKCONFIG_PROC:

This option enables access to the kernel configuration file through
/proc/config.gz. 
""""

So depending on the kernel config /proc/config.gz may or may not exist.  
I don't have the first option enabled here so don't see the second, and 
don't have that proc file.

However, you did say "try".  If genkernel enables it by default, 
presumably those using genkernel would either have the file, or would 
know enough about kernel functionality to either fix the problem on their 
own or at least be able to translate your instructions into something 
approaching "copy your kernel config from wherever you put it to the 
kernel working dir".

Talking about the kernel working dir, it's also worth noting that can be 
set as well, using the O=dir kernel make option (as mentioned in make 
help) or by setting and exporting the KBUILD_OUTPUT environmental 
variable appropriately.  Setting that keeps the kernel sources pristine 
(save for the output-dir itself, if set to within the kernel tree as it 
will be if an absolute path is not used), with all output (including 
the .config file) directed to the output dir, thus making cleanup far 
easier as well as tracking a kernel git repository, for those who wish to 
do so. I've used "outputdir" as my build/working dir for some time, so 
have /usr/src/linux/outputdir/.config instead of /usr/src/linux/.config .

Note that for purposes of building out-of-tree kernel modules such as
the ati-drivers under discussion here, exporting KBUILD_OUTPUT is 
easiest, and setting it in make.conf should be all that's necessary for 
packages installed using portage.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman