Loading custom DSDT

[Richard Hughes]

On Tue, 2005-10-25 at 14:07 +0200, Thorsten Leemhuis wrote:
> Am Dienstag, den 25.10.2005, 12:08 +0100 schrieb Richard Hughes:
> > What is the fedora "recommended" way of installing a new ACPI DSDT? Can
> > we make the process of loading a new asl file easier for users in FC5? 
> 
> See this thread for some more information:
> 
> https://www.redhat.com/archives/fedora-test-list/2005-September/msg00287.html
> 
> And especially:
> https://www.redhat.com/archives/fedora-test-list/2005-September/msg00292.html
> https://www.redhat.com/archives/fedora-test-list/2005-September/msg00291.html
> https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=169014

Thanks for the links.

If Mandriva, SuSE and Ubuntu use this patch by default, then Fedora is
the only other big current distro (that I would consider enterprise
ready) to *not* support loading a custom dsdt.

To quote from Len Brown:
>  That said, it is useful for developers to be able to override the DSDT.
>  There are two methods -- re-build kernel or re-build kernel and also
>  modify the initrd.
>  
>  Kernel re-build is (I think) simple enought.  I think the patch at hand
>  takes it from simple to trivial.

You try telling a new user to recompile their kernel, from a src.rpm, with an
extra patch, into a new rpm, which they then have to install, and you'll
understand why I'm worried... Everytime a new kernel update comes along,
we have to go kernel-a-building yet again.

Which is fine if you are a kernel hacker, or an ACPI maintainer, but for
joe average, who just wants this "linux thing" to "just work" -- it's not
good enough.

And to quote Dave Jones:   	 
>If users start manipulating their DSDTs, and getting panics etc, they file bugs
>here, and would 'neglect' to say how they hacked their dsdt's
>It's a support nightmare waiting to happen.

If a user has to install a dsdt, it's to get ACPI working closer to the
ACPI standard. The kernel should work properly with a standard dsdt
layout, as opposed to a non-standard (and broken) dstd layout.

Has a user ever filed a bug with component kernel that failed to mention
he/she was using a custom, and broken dstd?

No-one's asking for vendor support for automatic override of a dsdt in
the initrd -- the user has to manually download the asl file and install
it even in Ubuntu.

Adding the patch to the fedora system allows the user to choose, as at
the moment, they have no choice. We could add a BIG FAT WARNING on boot
if we are using a custom dsdt, and hence make the override very obvious.

At the moment, should I tell my new-user to either switch to ubuntu,
suse or mandriva to use the corrected dsdt? Don't get me wrong, I love
Fedora, but I think sometimes we forget that users != developers.

Richard.