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[Javier Vasquez <j.e.vasquez.v AT gmail.com>]

On Sun, May 26, 2013 at 4:08 PM, Javier Vasquez <j.e.vasquez.v AT gmail.com> 
wrote:
> On Thu, May 23, 2013 at 10:15 AM, Treeve Jelbert <treeve AT scarlet.be> wrote:
>> On Wednesday 22 May 2013 22:31:52 Javier Vasquez wrote:
>>> ...
>>
>> ...
>
> udev 182 from devel-udev-kmod is missing a patch that removes sd_is_mq
> method, from source and header.  The reason is the method depends upon
> some stuff not available with glibc 2.17, so without the patch there's
> a build error.
>
> See upstream patch:
>
> https://github.com/gentoo/eudev/commit/3d6f228db94e8bfb81f3b163739250e9a578e819
>
> And see the comment on gentoo regarding it:
>
> https://github.com/gentoo/eudev/issues/41
>
> I already have installed kmod 12:
>
> % gaze versions kmod
> Grimoire    Section  Spell  Grimoire Version  Installed Version
> --------    -------  -----  ----------------  -----------------
> before      kernels  kmod   12                12
> test        kernels  kmod   5                 -
>
> Got it from from devel-kmod.  Things work just fine with it.
>
> However there's no way udev 182 works.
>
> It just gets into an infinite reboot loop as described previously.
> kmod seems not to be a problem at all, actually replacement of
> module-init-tools seems to have been transparent...
>
> I've read that it might be related to the lack of "CONFIG_DEVTMPFS=y",
> but I have it set on all my kernel versions.  What I do not have set
> is "CONFIG_DEVTMPFS_MOUNT".  I don't use initrd images at all, so I'm
> wondering if this could be it...
>
> Would you think this would be it?  If not, then I'm clueless...  I
> haven't found anything on the web, other than rebuid your initrd
> image, or use that config (which I already have)...


Actually that was it...

When attempting to "make menuconfig", and reading the help, I realized
there was a boot parameter to override behavior.  Default is off, but
I guess prior versions of udev, like 175, took care of mounting the
devtmpfs, and that now udev is no longer doing it.  I still want to
set the kernel option, and then leave the boot parameter for
modifications, as intended by the kernel.  I guess udev changed in
favor of binary distros which have initrd, therefore the initrd takes
care of mounting the devtmpfs, and they rather prefer not the kernel
neither udev to manage that...

The boot parameter BTW is:

devtmpfs.mount=1

Here it's a reference that doesn't explain the new need for
CONFIG_DEVTMPFS_MOUNT, neither it indicates it's required (at least
not at the moment published), but which gives the hint:

http://www.mygnu.de/index.php/2012/03/udev-182-needs-config_-devtmpfs-in-kernel

I'm compiling the kernel, and I'll test with no boot parameters
afterwords, but it looks like it'll do the trick, :-)

So kmod 12 + udev 182 can be used afterwords...  However for udev 182
a new patch is required (glibc 2.17 issue), and the kernel needs
CONFIG_DEVTMPFS_MOUNT set.  I didn't test other kmod earlier than 12,
so I wouldn't know of the interactions with earlier kmods...  I did
test both 64 and 32 bits...

I'll update the bug later, when not needing the boot parameter, :-)

Thanks,

--
Javier.